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. 2025 Sep 28;10(39):45090–45102. doi: 10.1021/acsomega.5c03931

Enhanced Photocatalytic Degradation of trypan Blue Dye by Copper Sulfide Nanoparticles Prepared from 4‑Benzylpiperazinyldithiocarbamate Copper(II) Complex

Peter A Ajibade †,*, Fartisincha P Andrew †, Thandi B Mbuyazi †, Tshephiso R Papo †, Fahad I Danladi ‡, Abhishek Rawat ‡, Chuzhong Zhang §, Krishnan Rajeshwar ‡
PMCID: PMC12508933  PMID: 41078747

Abstract

The copper­(II) complex of 4-benzylpiperazinyldithiocarbamate was synthesized and characterized by spectroscopic techniques and single crystal X-ray crystallography. The single crystal X-ray structure of the compound revealed a centrosymmetric dimeric molecule with the copper­(II) ions situated in a distorted five-coordinate square pyramidal environment. The complex was used as a single source precursor for the preparation of copper sulfide nanoparticles capped with three capping agents, octadecylamine (ODA), dodecylamine (DDA), and hexadecylamine (HDA) and at three different temperatures, 120 °C, 160 °C and 220 °C. Powder X-ray diffraction patterns confirmed mainly chalcocite crystalline phases of copper sulfide with some minor peaks of roxbyite phase. The optical band gaps for the nanoparticles range from 4.07 to 4.16 eV, with a maximum absorption band edge of 283.7 nm. The morphological studies revealed different shapes ranging from spherical, hexagonal, and irregular shapes with average particle sizes ranging from 4.1 to 74.7 nm. The photocatalytic studies of the nanoparticles under visible light demonstrated an efficient photodegradation of trypan blue dye. Dodecylamine capped copper sulfide nanoparticles (CuS-DDA) and copper sulfide prepared at 120 °C (CuS-120) achieved 99.31% and 99.26% photocatalytic degradation efficiency with a rate constant of 0.03045 and 0.02749 min–1, respectively. Scavenger studies revealed the role of reactive species in trypan blue degradation by copper sulfide nanoparticles. Recyclability experiments showed excellent stability and reusability of the nanoparticles, demonstrating their potential for sustained photocatalytic applications.

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Introduction

Rapid industrialization in the 21st century and the explosive development of the textile and pharmaceutical industries have led to the continuous discharge of organic dyes and other pollutants into aquatic ecosystems. The presence of various organic dyes in industrial wastewater has resulted in serious environmental pollution. , These contaminants are nonbiodegradable and carcinogenic materials that are harmful to human beings. Even small quantities (less than 1 ppm) of organic dyes can seriously pollute water bodies. , In the textile industry, organic dyes are one of the most used synthetic materials that give fabrics their vibrant colors. − Most of these dyes are carcinogenic and interfere with the proper functioning of the aquatic ecosystem by limiting the amount of light, which is necessary for photosynthesis. − There is an ongoing effort to develop efficient techniques to remove these dyes from the aquatic ecosystems − which will serve as efficient detoxification/remediation of these pollutants from water bodies without producing any secondary contaminants. , Therefore, the removal of organic dyes from wastewater streams is a critical environmental issue that requires urgent attention.

Adsorption and coagulation methods are used to remove organic contaminants. − However, this would eventually lead to the generation of secondary contaminants because the dyes are transformed into solid products which are secondary contaminants. , Several methods have been developed to remove these pollutants from the ecosystems, but they have inherent limitations. − These limitations have led to the development of advanced oxidation processes (AOPs) such as heterogeneous photocatalysis. −

Heterogeneous photocatalysis uses solar energy to chemical energy through photogenerated electrons from semiconductor materials or photocatalysts to degrade the organic pollutants or to remove heavy metal ions. − Several metal oxides have been used as photocatalysts for the degradation of organic dyes, but their wide band gap reduces their photocatalytic efficiency. − Apart from metal oxides, metal sulfide nanoparticles such as molybdenum disulfide (MoS2), , tungsten disulfide (WS2), , copper sulfide (CuS), , cadmium sulfide (CdS), , lead sulfide (PbS) , and tin sulfide (SnS) ,,,, with unique properties, narrow bandgaps, and high carrier mobility have been studied as photocatalysts. Among these metal sulfides, copper sulfide nanoparticles are attractive candidates because they are environmentally friendly and highly efficient as photocatalysts for the degradation of organic dyes. − Copper sulfide nanoparticles exist in different crystalline phases, and their photocatalytic degradation efficiency depends on the morphological properties and crystalline phases. In this study, we present the effect of capping agents and the thermolysis temperature on the morphological, optical, and photocatalytic degradation of a trypan blue dye by the as-prepared copper sulfide nanoparticles.

Results and Discussion

Molecular Structure of 4-Benzylpiperazinyldithiocarbamate Copper­(II) Complex [Cu2(4-bppdtc)4]

Single crystals of the 4-benzylpiperadinyldithiocarbamate copper­(II) complex were obtained by layering a dimethyl sulfoxide solution of the complex with methanol and allowing it to evaporate slowly at room temperature. The crystallographic data and selected bond lengths and bond angles are presented in Tables S1 and S2, respectively. The molecular structure of the complex is shown in Figure . Hydrogen atoms have been omitted (Figure B) for clarity. The unit cell diagram viewed down the crystallographic b-axis is shown in Figure S1. The complex formed a centrosymmetric dimeric structure. Each unit of the dimer consisted of copper­(II) ions coordinated to two molecules of the 4-benzylpiperadinyldithiocarbamato ligands. One ligand bidentately coordinated the copper­(II) ion, and the other ligand simultaneously bound the copper­(II) ion and bridged the other unit, forming four equatorial Cu·····S bonds at the plane and a fifth axial bridging bond with the second molecular unit of the dimer. The four equatorial bond lengths Cu1–S11, Cu1–S12, Cu1–S21 and Cu1–S22 have values of 2.3260(6) 2.3102(5), 2.3218(6), and 2.2906(5) Å, respectively. The axial bridging Cu·····S (Cu1–S11, 2.8022(5) Å) bond was weak and a bit longer than the Cu·····S equatorial bonds analogous to dimeric copper­(II) dithiocarbamate complexes. −

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Molecular structure of centrosymmetric [Cu2(4-bppdtc)4] with hydrogen atoms (A), with hydrogen atoms omitted (B) for clarity and regular chemical structure of the compound (C).

The equatorial bond angles S21–Cu1–S22 and S11–Cu1–S12 were nearly similar, 77.34(2)° and 76.78(2)°, respectively. The bridging network Cu1–S11–Cu1(#)–S11(#) was planar due to the inversion center with a diagonal Cu·····Cu separation distance of 3.549 Å. The plane formed by the four equatorial sulfur atoms (S11, S12, S21 and S22) was almost perpendicular to the bridging network (Cu1–S11–Cu1(#)–S11(#)) with a dihedral angle of 87.06(2)°. This is like the dimeric copper­(II) dithiocarbamate complexes reported. The coordination geometry around the copper­(II) ions is best described as a distorted square pyramidal geometry. The distortion might be due to the steric restriction imposed by the substituents on the thioureide (−NCS2) back-bond. The entire structure was stabilized by C–H·····π, CH·····π and π·····π secondary interactions.

Spectroscopic Characterization of [Cu2(4-bppdtc)4]

The electronic spectra of the ligand and the complex (Figure S5) show absorption bands at 263 and 282 nm in the ligand and 243, 271, and 291 nm in the complex ascribed to the intraligand n−π* and π–π* electronic transitions. The medium absorption band at 433 nm is due to the metal to ligand charge transfer transitions. In this case, the d-orbitals of the copper­(II) ion interacted with the highest occupied π-orbitals of the sulfur atoms in the ligand, which enhances the overall structural stability of the complex. A weak broad band at 617 nm in the absorption spectra of the complex was a ligand field (d–d) transition.

The overlay Fourier transform infrared (FTIR) spectra of the ligand and the [Cu2(4-bppdtc)4] complex (Figure S6) revealed strong absorption bands in the range 920–1988 cm–1 for the ligand and at 961 cm–1 in the spectrum of the complex assigned to the ν­(C–S) stretching vibrations of the C–S2 moiety of the dithiocarbamate. Strong and sharp bands observed in the ranges 1414–1467 cm–1 and 1430–1477 cm–1 in the ligand and the complex, respectively, were assigned to the ν­(N–CS2) stretching vibration. Weak absorption bands, 1621–1666 cm–1 observed in the ligand and 1603 cm–1 in the complex, were assigned to the aromatic ν­(CC) stretching vibrations. In addition, the aromatic ν­(C–H) stretching vibration was observed in the range 2849–3354 cm–1 in the ligand and 2915 cm–1 in the complex. The shift and decrease in intensity of these bands upon coordination to the copper­(II) is ascribed to the delocalization of the electrons within the dithiocarbamate ion moieties and confirmed by the molecular structure of the compound. −

Morphological Studies

The copper sulfide nanoparticles were synthesized via thermolysis of the precursor complex in the presence of different capping agents (DDA, HDA, or ODA) at varying temperatures. The surface morphologies of the nanoparticles were determined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The TEM images and the particle size distribution histograms are shown in Figures and Figure S7. The SEM images are shown in Figure S8. The SEM images revealed both anisotropic and isotropic structural morphologies of copper sulfide nanoparticles, which include hexagonal, distorted hexagonal, spherical, rod-like, flower-petal-like, sponge-like, and irregular shapes. CuS-160, CuS-DDA, and CuS-ODA showed hexagonal-shaped particles in the SEM images. CuS-120 and CuS-220 images showed a layered structure with a mixture of mostly rod-like, spherical, and irregular shapes. Conversely, CuS-HDA showed a flower petal/sponge-like shape with some spherical and rod-like particles embedded within the structure. The anisotropic shapes observed could be due to the nature of the capping agents and the temperature variation. −

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TEM images of the copper sulfide nanoparticles prepared at different capping agents (left-hand frames) and for different temperatures (right-hand frames).

CuS–DDA and CuS–160 TEM images exhibited the hexagonal platelet morphology, with sizes of 74.7 and 50.9 nm, respectively. In contrast, CuS–HDA revealed spherical and irregular shaped particles with an average size of 18.8 nm. CuS–ODA displayed a mixed morphology of both hexagonal platelets and dots at an average size of 29.8 nm. The smallest particles were obtained at 120 °C (CuS 120) and formed fine dots with an average size of 4.1 nm. CuS–220 exhibited chain-like structures with a size of 37.7 nm, which may result from enhanced crystal growth mechanisms at elevated temperatures. The agglomeration observed may be due to weak physical forces and a high surface area-to-volume ratio.

Elemental mapping of the nanoparticles was done by energy-dispersive X-ray spectroscopy (EDS). Integrated area EDS data together with the weight percentage of the constituent elements are shown in Figure S9. From the spectra, the observed peaks corresponding to Cu and S suggest the formation of the copper sulfide nanoparticles. The elemental mapping micrographs are shown in Figure S10 and suggest a homogeneous lateral distribution on the surface.

Powder X-ray Diffraction Patterns of the Copper Sulfide Nanoparticles

The crystalline structure of the synthesized copper sulfide nanoparticles was characterized by using powder X-ray diffraction (Figure ). The diffraction peaks were primarily indexed to the chalcocite phase (Cu2S), based on standard reference data (JCPDS 033-0490). , The observed peaks at 2θ values of 7.11°, 11.92°, 16.93°, 22.23°, 24.29°, 25.47°, 27.43°, 30.87°, 34.60°, 36.27°, 39.71°, 41.18°, 42.76°, 44.13°, 47.08°, 48.35°, 49.73°, and 54.83° correspond to the (001), (011), (012), (212), (2̅04), (1̅04), (1̅14), (132), (3̅15), (142), (422), (3̅16), (630), (106), (6̅43), (532), (07̅1), and (264̅) lattice planes, respectively. In addition to the main chalcocite phase, minor peaks marked with asterisks were identified and matched with the roxbyite phase (Cu58S32) of PDF# 00-064-0278. Chalcocite is a stable and well-defined phase, while roxbyite is less stable, contains more copper, and can change into Cu2S when exposed to conditions with more sulfur. , Therefore, the stability difference suggests that the presence of roxbyite may be attributed to the fluctuation of reaction conditions during synthesis. Capping agents modulate the crystal growth direction by altering the surface chemistry, ligand binding strength, and steric hindrance. HDA, DDA, and ODA capped nanoparticles show the same crystalline phase with different preferred orientations, highlighting the tunability of Cu2S nanoparticles by organic ligands. Copper sulfide nanoparticles prepared at different temperatures exhibit the same crystalline phase. However, higher synthesis temperatures enhance crystallinity and induce a shift in preferred orientation from (212) to (2̅04).

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Powder X-ray diffraction patterns of the as-prepared copper sulfide nanoparticles (A) prepared with different capping agents and (B) prepared at different temperatures.

Optical Properties of the CuS-Nanoparticles

The optical properties of nanomaterials are largely dependent on composition, particle size, shape, phase structure, and surface states. The optical absorption spectra (Figure S11) of the copper sulfide nanoparticles show the absorption band edges at 284 nm for the CuS-ODA, CuS-DDA, and CuS-HDA, while for CuS-120, CuS-160 and CuS-220, the absorption band edge is 283.7 nm. The direct band gaps of the as-prepared nanoparticles were determined using Tauc’s plot − (Figure S12).

The band gaps of the copper sulfide nanoparticles, namely CuS-120, CuS-160, CuS-220, CuS-ODA, CuS-DDA and CuS-HDA, were found to be in the ranges 4.107 eV < Eg < 4.154 eV, 4.116 eV < Eg < 4.162 eV, 4.122 eV < Eg < 4.163 eV, 4.124 eV < Eg < 4.162 eV, 4.070 eV < Eg < 4.133 eV, and 4.065 eV < Eg < 4.147, respectively. The obtained band gap values were slightly above those reported in the literature, − a trend that could be attributed to nanoparticle size and surface structure variations. The larger values in this study translate to a finer nanoparticle range for the samples in this study relative to those utilized in previous studies. −

FTIR Spectra Studies

Figure shows the overlay spectra of the capping agents, the nanoparticles prepared with the capping agents (A), and the nanoparticles prepared at different temperatures (B). The spectra showed characteristic vibrational stretching frequencies for the N–H stretching vibration of amines in the range 3384–3240 cm–1. The shift in vibrational frequency of the as-prepared nanoparticles in comparison to that of the capping agent toward higher wave numbers indicated that the N–H functional group was bound to the copper sulfide surface by an electron-donating nitrogen atom through noncovalent interactions. The broad bands observed in the ranges 2912–2921 cm–1 and 2847–2855 cm–1 were associated with the symmetric and asymmetric vibrational stretching of ethylene (CH2) groups in the dispersant and capping agents and with little shift in the nanoparticle spectra. Similarly, N–H and C–N stretching vibrations were observed in the range 1635–1461 cm–1 and 1316–1030 cm–1, respectively. Sharp stretching vibrations in the range 714–794 cm–1 were assigned to C–H stretching vibrations. These results are consistent with previous studies. − No significant shifts in the peaks were observed after the copper sulfide nanoparticles were used as photocatalysts for trypan blue degradation (Figure S15).

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FTIR spectra of the capping agents and copper sulfide nanoparticles with different capping agents (A) and at different thermolysis times (B).

Photocatalytic Degradation and Kinetic Studies

The photocatalytic degradation potential of the copper sulfide nanoparticles was investigated for the degradation of trypan blue dye under a mercury lamp as visible light radiation source. The maximum absorptions of the dye solution in the presence of CuS-120, CuS-160, CuS-220, CuS-ODA, CuS-DDA and CuS-HDA were 593, 598, 596, 598, 594, and 593 nm, respectively. These absorptions corresponded to the n-π* transition and the azo linkage. The dye solution was exposed to visible light irradiation in the absence and presence of the photocatalyst at various time intervals. The spectra as a function of irradiation time (Figure S13) showed a decrease of the absorbance maxima with time in the presence of the photocatalysts. The photocatalytic degradation efficiency plots (Figure ) show that CuS-120, CuS-160, CuS-220, CuS-DDA, CuS-HDA, and CuS-ODA degraded 99.26%, 98.57%, 91.45%, 99.31%, 97.47%, and 65.08% of the trypan blue dye after 180 min. The comparatively smaller nanoparticles (CuS–HDA, CuS–120, CuS–220) show high photocatalytic efficiency due to their large surface area. Similarly, the larger hexagonal-shaped nanoparticles (CuS–DDA and CuS–160) exhibit enhanced photocatalytic activity, due to their distinct morphology, which exposes additional active sites. The hexagonal shape typically results in high crystallinity with exposed facets, promoting effective charge separation and transfer during the photocatalytic reaction. CuS-ODA showed significantly lower photocatalytic degradation efficiency relative to those of the other photocatalysts. This may be attributed to its low crystallinity, which suggests higher defect density. These defects act as recombination centers for photogenerated electron–hole pairs, limiting reactive species generation, which reduces photocatalytic activity. ,

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Degradation efficiency of the dye in the presence of the nanoparticles.

The kinetics of the photocatalytic degradation process of the dye by the nano-photocatalyst was studied using the Langmuir–Hinshelwood model. Figure shows the plot of the ratio of final and initial concentration (C t /C 0) versus time (t) and the plot of the natural logarithm of the ratio of the initial and final concentration (ln­(C 0/C t )) of the dye solution versus the irradiation time (t) in the presence of the copper sulfide nanoparticles. The result indicated a linear relationship, and the photodegradation rate of trypan blue dye by the as-prepared copper sulfide nanoparticles followed pseudo-first-order kinetics.

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Concentration curves (a, b) and kinetics (c, d) of the trypan blue dye degradation in the presence of CuS-ODA, CuS-DDA, CuS-HDA, CuS-120, CuS-160, and CuS-220 nanoparticles photocatalyst.

The percentage degradation efficiency, rate constant, R-square value, and half-life obtained from the kinetic data are listed in Table . The dye concentration has a negative effect on the rate constant of photodegradation, with the rate constant (k) decreasing with increased initial dye concentration. This trend is consistent with reported findings.

1. Percentage Degradation, Rate Constant, R-Square Value, and Half-Life of trypan Blue Dye Degradation by CuS-Nanoparticles.

Photocatalyst % Photo­ degradation Rate constant (min –1 ) R 2 value Half-life (min)
CuS-ODA 65.08 0.00588 ± 0.00084 0.908 117.86
CuS-DDA 99.31 0.03045 ± 0.0045 0.902 22.76
CuS-HDA 97.47 0.02017 ± 0.00297 0.902 34.36
CuS-120 99.26 0.02749 ± 0.00315 0.938 25.21
CuS-160 98.57 0.02173 ± 0.00234 0.945 31.89
CuS-220 91.45 0.01225 ± 0.00275 0.799 56.57
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Effect of Scavengers

The bar graphs in Figure illustrate the influence of various scavengers on the photocatalytic degradation efficiency of trypan blue dye by using the as-prepared copper sulfide nanoparticles. The highest degradation efficiency was obtained in the absence of scavengers, with CuS–120 and CuS–DDA achieving over 99% degradation, demonstrating their strong photocatalytic activity. The introduction of scavengers led to varying reductions in efficiency, which confirms the roles of reactive species in the degradation process. For CuS–120 and CuS–220, the degradation efficiency decreased significantly with SN, followed by IPA and FA, which is an indication that electrons played the most significant role, followed by hydroxyl radicals (•OH), holes (h+), and superoxide radicals (•O2 –). In CuS–160, degradation was mostly affected by SN (19.85%) and FA (21.62%), indicating a slightly different reactive oxygen species hierarchy as follows: e– > h+ > •OH > •O2 –. In CuS–DDA, the highest suppression was observed with IPA (14.79%), implying that hydroxyl radicals were the dominant species, followed by electrons, superoxide radicals, and holes. For CuS–HDA, degradation was primarily influenced by SN (12.32%) and BQ (27.77%), highlighting the significance of electrons and superoxide radicals. CuS–ODA exhibited the highest inhibition with IPA (16.95%) and FA (25.27%), which indicates that hydroxyl radicals and holes were the most active species in this system, while electrons and superoxide radicals played secondary roles. The results are consistent with those of other reported catalysts. , The differences in degradation efficiency and reactive species involvement suggest that synthesis temperature and capping agents significantly affect the surface properties, charge separation efficiency, and generation of reactive species in copper sulfide nanoparticles. ,

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Effect of different scavengers on the photocatalytic degradation efficiency of trypan blue dye using CuS nanoparticles synthesized (a) at different temperatures (CuS–120, CuS–160, CuS–220) and (b) with different capping agents (CuS–DDA, CuS–HDA, CuS–ODA).

Recyclability Studies

The recyclability of the CuS nanoparticles was evaluated over three consecutive photocatalytic cycles for the degradation of trypan blue, as shown in Figure . After three consecutive cycles, the degradation efficiencies decrease to 61.31%, 75.18%, and 70.07% for CuS–120, CuS–160, and CuS–220, respectively. Similarly, CuS–DDA, CuS–HDA, and CuS–ODA exhibited photodegradation efficiencies of 72.64%, 86.65%, and 63.03%, respectively. CuS–HDA exhibited superior performance, achieving high degradation in each cycle with minimal loss of activity, indicating excellent stability and reusability. CuS–DDA and CuS–ODA exhibited good photostability and greater retention of activity over three cycles. In contrast, CuS–120 and CuS–160 demonstrated a progressive decline in activity across cycles. The decrease in degradation efficiency could be attributed to the blockage of active catalytic sites by accumulated degradation products during the reaction, as well as agglomeration of nanoparticles. The TEM and FTIR spectra of the copper sulfide nanoparticles after three photocatalytic cycles are presented in Figures S14 and S15. It is observed that the morphology of the nanoparticles after the photocatalytic reaction is similar to that of particles before the experiment, with some degree of agglomeration. FTIR also shows the presence of capping agents on the nanoparticles, which indicates that the capping agents do not decompose during the photocatalytic reaction. These results show the significance of both the synthesis temperature and the use of capping agents in tailoring CuS nanoparticles for effective and reusable photocatalytic applications.

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Recyclability studies of (a) CuS–120, (b) CuS–160, (c) CuS–220, (d) CuS–DDA, (e) CuS–ODA, and (f) CuS–HDA nanoparticles for the photocatalytic degradation of trypan blue over three consecutive cycles.

Conclusions

Bis­(benzylpiperadinyldithiocarbamato)­copper­(II) complex was synthesized and characterized by single crystal X-ray crystallography and spectroscopic techniques. The molecular structure revealed a centrosymmetric dimeric molecule with space group P21/C with the copper­(II) ions in a distorted five-coordinate square pyramidal geometry. The complex was used as a single source precursor to prepare copper sulfide nanoparticles using three different capping agents at three different temperatures. The effects of the capping agents and different thermolysis temperatures on the morphology and photocatalytic degradation efficiency were studied. The TEM and SEM images revealed both anisotropic and isotropic structural morphologies of the copper sulfide nanoparticles. An average particle size of 4.1–74.7 nm and energy band gap of 4.07–4.16 eV was observed. The photocatalytic degradation performance of the nanoparticles prepared with different capping agents followed the order CuS-DDA > CuS-HDA > CuS-ODA with degradation efficiencies of 99.31%, 97.47%, and 65.08%, respectively. The nanoparticles prepared at the temperatures 120, 160, and 220 °C followed the order CuS-120 > CuS-160 > CuS-220 with the values 99.26%, 98.57%, and 91.45%, respectively, after a 180 min irradiation time. The kinetics of the photocatalytic degradation of the dye in the presence of the nanoparticles revealed a pseudo-first-order kinetics behavior. The scavenger studies confirmed the role of reactive species in the photocatalytic degradation of trypan blue by the copper sulfide nanoparticles. Recyclability studies revealed that the nanoparticles exhibited excellent reusability and stability, with postreaction analyses confirming minimal morphological changes.

Experimental Section

Materials and Methods

Materials

4-Benzylpiperadine, copper­(II)­chloride, sodium hydroxide, carbon disulfide octadecylamine (ODA), dodecylamine (DDA), hexadecylamine (HDA), trioctylphosphine (TOP), silver nitrate, formic acid, benzoquinone, and all of the solvents were of analytical grade purchased from Merck and used as obtained without any further purification.

Synthesis of 4-Benzylpiperadinyldithiocarbamato Copper­(II)

4-Benzylpiperadinyldithiocarbamate and the copper­(II) complex were prepared following a literature procedure with modification. An aqueous solution of sodium hydroxide (0.05 mol, 2 g) was added to equimolar methanolic solutions of N-benzylmethylamine (0.05 mol, 6.060 g) and stirred at room temperature for 30 min. The temperature of the solution was brought down to 4 °C; carbon disulfide (0.05 mol, 3.807 g) was added dropwise, and the mixture was stirred for 3 h. The resulting precipitate obtained was filtered, washed thoroughly with diethyl ether, and dried in a desiccator over silica gel.

The metal complex was synthesized by reacting aqueous solutions of copper­(I) chloride (0.005 mol, 0.495 g) and the ligand (0.005 mol, 1.367 g) at room temperature while the mixture was stirred for 3 h. The resulting precipitate was filtered, washed several times with water, and dried in a desiccator over silica. Crystals were obtained within a few weeks by solvent layering and slow evaporation.

Ligand

Yield; 60.86%. Color: white, UV–Vis (H2O, λmax, nm) 283. 1H NMR (400 MHz, D2O, δ, ppm), 7.34 (t, 2H), 7.25 (t, 2H), 5.37 (d, 1H), 3.08 (t, 4H), 2.57 (d, 2H) 1.68 (d, 1H), 1.24 (q, 4H). 13C NMR (400 MHz, D2O, δ, ppm), 205.64 (CS), 141.13, 129.35, 128.48, 126.07 (−C6H5), 41.64 (−CH2), 52.02, 37.25, 31.50 (−CH4CHCH4). Selected FTIR ν­(cm–1); 921 (C–S), 1172 (C–N), 1414,1465 (CS), 1620 (N–H), 2938, 2848 (−CH2), 3352 (C–H).

Complex

Yield: 94.02% Color: Yellow solid, UV–Vis (DCM, λmax, nm) 242, 433. Selected FTIR ν­(cm–1); 921 (C–S), 1172 (C–N), 1414,1465 (CS), 1620 (N–H), 2938, 2848 (−CH2), 3352 (C–H).

Synthesis of Copper Sulfide Nanoparticles

The nanoparticles were prepared according to the literature with modification. In a typical experiment, 4 g of each capping agent, namely, octadecylamine (ODA), dodecylamine (DDA), and hexadecylamine (HDA), was charged into a three-necked flask fitted with a reflux condenser, thermometer, and a rubber septum. It was then heated to 150 °C for the capping agent to melt under nitrogen. The 4-benzylpiperadinyldithiocarbamato copper­(II) complex (0.4 g) dispersed in 2 mL of trioctylphosphine (TOP) was injected into the hot capping agent. The reaction mixture was maintained at 150 °C under an inert nitrogen environment for 1 h. The resulting product was cooled to 60 °C and cold methanol was added. The precipitate was centrifuged, washed several times with cold methanol, and dried under a vacuum. The nanoparticles were labeled CuS-ODA, CuS-DDA, and CuS-HDA. Similarly, using octadecylamine as a capping agent and the same conditions stated above, three more samples of CuS nanoparticles were synthesized varying the temperature of the thermolysis at 120 °C, 160 °C and 220 °C. The resulting nanoparticles were labeled CuS-120, CuS-160, and CuS-220, respectively.

Characterization Techniques

Transmission electron microscopy (TEM) images were obtained on a Jeol JEM-1400 electron microscope. Scanning electron microscopy (SEM) and electron dispersive X-ray spectroscopy (EDX) spectra were performed on a ZEISS EVO LS15 electron microscope. UV–visible spectra and FTIR were recorded using a PerkinElmer Lambda 25 spectrometer (200–700 nm) and Bruker Alpha II spectrometer (4000–500 cm–1).

X-ray Data Collection and Structure Refinement

The single crystal X-ray data of the complex were collected using a Bruker APEX-II CCD diffractometer (Billerica, MA, USA) at 200 K using Mo-Kα radiation. Data reduction and refinement were done using Olex2 and SHELXL-2018/3 programs. − All non-hydrogen atoms were refined anisotropically.

Photocatalytic Degradation

The photocatalytic degradation potential of the copper sulfide nanoparticles was evaluated against trypan blue dye using an OSRAM HQL (MBF-U) 125W lamp as a visible light source; 35 mg of each nanoparticle was added to 35 mL of an 10 mg/L aqueous solution of the dye. The solution was sonicated for 30 min and stirred in the dark for 30 min to establish an adsorption–desorption equilibrium of the dye on the catalyst surface. The reaction solution was irradiated under visible light for 180 min. 5 mL aliquots of the sample were collected at 30 min intervals, and the absorption spectrum was recorded. The degradation efficiency was determined using eq .

D=C0−CtC0×100 1

where D is the degradation efficiency, C 0 and C t are initial and final concentration of the dye, respectively.

The pseudo-first-order reaction kinetics of the photodegradation of the trypan blue dye in the presence of the nanoparticles were evaluated using eq :

ln(C0Ct)=kL−HKadt=kt 2

Radical Scavengers Experiment

Radical scavenging experiments were conducted to identify the dominant reactive species in the trypan blue degradation. Silver nitrate (SN), benzoquinone (BQ), formic acid (FA), and isopropanol (IPA) selectively inhibited electrons (e–), superoxide radicals (•O2 –), photogenerated holes (h+), and hydroxyl radicals (•OH), respectively. Each scavenger (10 mM) was added to the dye–catalyst suspension to achieve a final concentration of 1 mM in a 35 mL reaction volume. Under visible light irradiation for 180 min, dye degradation was monitored using a UV–Vis spectrophotometer at 30 min intervals.

Supplementary Material

ao5c03931_si_001.pdf (2.2MB, pdf)

Acknowledgments

The authors would like to thank the National Research Foundation (NRF) South Africa for the award of competitive funding for rated researcher (Grant Number: CPRR23042396404) and the United States Fulbright Scholar program, TBM acknowledge the award of NRF-DAAD PhD scholarship and FPA thanks Modibbo Adam University, Yola, Nigeria, for postdoctoral leave.

The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acsomega.5c03931.

  • Crystal-packing diagram of view down the crystallographic b-axis (Figure S1); Mass spectrum of copper complex (Figure S2); 1H NMR spectrum of 4-benzylpiperazinyl dithiocarbamate ligand (Figure S3); 13C NMR spectrum of 4-benzylpiperazinyl dithiocarbamate ligand (Figure S4); Absorption spectra of 4-benzylpiperadinyldithiocarbamate ligand and its copper­(II) complex (Figure S5); FTIR spectra of 4-benzylpiperadinyldithiocarbamate ligand and its copper­(II) complex (Figure S6); Particle size distributions of the as-prepared nanoparticles (Figure S7); SEM Images of the copper sulfide nanoparticles prepared at different temperatures and with different capping agents: CuS-120, CuS-160, CuS-220, CuS-HDA, CuS-DDA and CuS-ODA (Figure S8); EDS data for the CuS-nanoparticles (Figure S9); Element mapping of the CuS-nanoparticles prepared at different temperatures and for capping agents (Figure S10); Absorption spectra of the nanoparticles (Figure S11); Tauc plots for the nanoparticles prepared with different capping agents and at different temperatures (Figure S12); Time dependent (0–180 min) spectra of photocatalytic degradation of Trypan blue dye in the presence of CuS-120, CuS-160 and CuS-22, CuS-ODA, CuS-DDA and CuS-HDA nanoparticle photocatalyst under visible light (Figure S13); TEM images of copper sulfide nanoparticles after three photocatalytic cycles (Figure S14); FTIR spectra of copper sulfide nanoparticles after three photocatalytic cycles (Figure S15); Single crystal data and structure refinement (Table S1); Bond lengths and bond angles (Table S2). (PDF)

CCDC 2306646 contains the supplementary crystallographic data for this paper. The data can be obtained free of charge at www.ccdc.cam.ac.uk/structures or from the Cambridge crystallographic data center, 12 Union Road, Cambridge, CB2 1EZ, UK; fax: (+44)-1223-336-033.

The authors declare no competing financial interest.

References

  1. Chowdhury A. P., Shambharkar B. H., Ghugal S. G., Umare S. S., Shende A. G.. Ethylene glycol mediated synthesis of SnS quantum dots and their application towards degradation of eosin yellow and brilliant green dyes under solar irradiation. RSC Adv. 2016;6:108290–108297. doi: 10.1039/C6RA10532G. [DOI] [Google Scholar]
  2. Olisah C., Adams J. B., Rubidge G.. The state of persistent organic pollutants in South African estuaries: A review of environmental exposure and sources. Ecotoxicol. Environ. Saf. 2021;219:112316. doi: 10.1016/j.ecoenv.2021.112316. [DOI] [PubMed] [Google Scholar]
  3. Mbuyazi T. B., Ajibade P. A.. Photocatalytic degradation of organic dyes by magnetite anoparticles prepared by co-precipitation. Int. J. Mol. Sci. 2024;25:7876. doi: 10.3390/ijms25147876. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Hanafi M. F., Sapawe N.. A review on the water problem associate with organic pollutants derived from phenol, methyl orange, and remazol brilliant blue dyes. Mater. Today Proc. 2020;31:A141–A150. doi: 10.1016/j.matpr.2021.01.258. [DOI] [Google Scholar]
  5. Chen D., Cheng Y., Zhou N., Chen P., Wang Y., Li K., Huo S., Cheng P., Peng P., Zhang R.. Photocatalytic degradation of organic pollutants using TiO2-based photocatalysts: A review. J. Clean. Prod. 2020;268:121725. doi: 10.1016/j.jclepro.2020.121725. [DOI] [Google Scholar]
  6. Benkhaya S., M’Rabet S., El Harfi A.. Classifications, properties, recent synthesis and applications of azo dyes. Heliyon. 2020;6:e03271. doi: 10.1016/j.heliyon.2020.e03271. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Repon M. R., Dev B., Rahman M. A., Jurkonienė S., Haji A., Alim M. A., Kumpikaitė E.. Textile dyeing using natural mordants and dyes: A review. Environ. Chem. Lett. 2024;22:1473–1520. doi: 10.1007/s10311-024-01716-4. [DOI] [Google Scholar]
  8. Dutta S., Adhikary S., Bhattacharya S., Roy D., Chatterjee S., Chakraborty A., Rajak P.. Contamination of textile dyes in aquatic environment: Adverse impacts on aquatic ecosystem and human health, and its management using bioremediation. J. Environ. Manage. 2024;353:120103. doi: 10.1016/j.jenvman.2024.120103. [DOI] [PubMed] [Google Scholar]
  9. John A., Yang H.-H., Muhammad S., Khan Z. I., Yu H., Luqman M., Tofail M., Hussain M. I., Awan M. U.. Cross talk between synthetic food colors (azo dyes), oral flora, and cardiovascular disorders. Appl. Sci. 2022;12:7084. doi: 10.3390/app12147084. [DOI] [Google Scholar]
  10. Sharma J., Sharma S., Soni V.. Classification and impact of synthetic textile dyes on Aquatic Flora: A review. Reg. Stud. Mar. Sci. 2021;45:101802. doi: 10.1016/j.rsma.2021.101802. [DOI] [Google Scholar]
  11. Alsukaibi A. K.. Various approaches for the detoxification of toxic dyes in wastewater. Processes. 2022;10:1968. doi: 10.3390/pr10101968. [DOI] [Google Scholar]
  12. Kubra K. T., Salman M. S., Hasan M. N.. Enhanced toxic dye removal from wastewater using biodegradable polymeric natural adsorbent. J. Mol. Liq. 2021;328:115468. doi: 10.1016/j.molliq.2021.115468. [DOI] [Google Scholar]
  13. Shin J.-H., Yang J. E., Park J. E., Jeong S.-W., Choi S.-J., Choi Y. J., Jeon J.. Rapid and efficient removal of anionic dye in water using a chitosan-coated iron oxide-immobilized polyvinylidene fluoride membrane. ACS Omega. 2022;7:8759–8766. doi: 10.1021/acsomega.1c06991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Natarajan S., Bajaj H. C., Tayade R. J.. Recent advances based on the synergetic effect of adsorption for removal of dyes from wastewater using photocatalytic process. J. Environ. Sci. 2018;65:201–222. doi: 10.1016/j.jes.2017.03.011. [DOI] [PubMed] [Google Scholar]
  15. Al-Nuaim M. A., Alwasiti A. A., Shnain Z. Y.. The photocatalytic process in the treatment of polluted water. Chem. Pap. 2023;77:677–701. doi: 10.1007/s11696-022-02468-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Brown M. A., De Vito S. C.. Predicting azo dye toxicity. Crit. Rev. Environ. Sci. Technol. 1993;23:249–324. doi: 10.1080/10643389309388453. [DOI] [Google Scholar]
  17. Moreira F. C., Boaventura R. A., Brillas E., Vilar V. J.. Electrochemical advanced oxidation processes: A review on their application to synthetic and real wastewaters. Appl. Catal., B. 2017;202:217–261. doi: 10.1016/j.apcatb.2016.08.037. [DOI] [Google Scholar]
  18. Ajibade P. A., Nnadozie E. C.. Synthesis and structural studies of manganese ferrite and zinc ferrite nanocomposites and their use as photoadsorbents for indigo carmine and methylene blue dyes. ACS omega. 2020;5:32386–32394. doi: 10.1021/acsomega.0c04404. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Kang D., Yu X., Ge M., Xiao F., Xu H.. Novel Al-doped carbon nanotubes with adsorption and coagulation promotion for organic pollutant removal. J. Environ. Sci. 2017;54:1–12. doi: 10.1016/j.jes.2016.04.022. [DOI] [PubMed] [Google Scholar]
  20. Jabbar K. Q., Barzinjy A. A., Hamad S. M.. Iron oxide nanoparticles: Preparation methods, functions, adsorption and coagulation/flocculation in wastewater treatment. Environ. Nanotechnol. Monit. Manag. 2022;17:100661. doi: 10.1016/j.enmm.2022.100661. [DOI] [Google Scholar]
  21. Lu F., Astruc D.. Nanocatalysts and other nanomaterials for water remediation from organic pollutants. Coord. Chem. Rev. 2020;408:213180. doi: 10.1016/j.ccr.2020.213180. [DOI] [Google Scholar]
  22. Foroutan R., Mohammadi R., Razeghi J., Ramavandi B.. Performance of algal activated carbon/Fe3O4 magnetic composite for cationic dyes removal from aqueous solutions. Algal Res. 2019;40:101509. doi: 10.1016/j.algal.2019.101509. [DOI] [Google Scholar]
  23. Kadam A. A., Lade H. S., Lee D. S., Govindwar S. P.. Zinc chloride as a coagulant for textile dyes and treatment of generated dye sludge under the solid state fermentation: Hybrid treatment strategy. Bioresour. Technol. 2015;176:38–46. doi: 10.1016/j.biortech.2014.10.137. [DOI] [PubMed] [Google Scholar]
  24. Wang Q., Ju J., Tan Y., Hao L., Ma Y., Wu Y., Zhang H., Xia Y., Sui K.. Controlled synthesis of sodium alginate electrospun nanofiber membranes for multi-occasion adsorption and separation of methylene blue. Carbohydr. Polym. 2019;205:125–134. doi: 10.1016/j.carbpol.2018.10.023. [DOI] [PubMed] [Google Scholar]
  25. Huang Y., Luo M., Xu Z., Zhang D., Li L.. Catalytic ozonation of organic contaminants in petrochemical wastewater with iron-nickel foam as catalyst. Sep. Purif. Technol. 2019;211:269–278. doi: 10.1016/j.seppur.2018.09.080. [DOI] [Google Scholar]
  26. Peydayesh M., Suter M. K., Bolisetty S., Boulos S., Handschin S., Nyström L., Mezzenga R.. Amyloid fibrils aerogel for sustainable removal of organic contaminants from water. Adv. Mater. 2020;32:1907932. doi: 10.1002/adma.201907932. [DOI] [PubMed] [Google Scholar]
  27. Muñoz-Morales M., Braojos M., Sáez C., Cañizares P., Rodrigo M.. Remediation of soils polluted with lindane using surfactant-aided soil washing and electrochemical oxidation. J. Hazard. Mater. 2017;339:232–238. doi: 10.1016/j.jhazmat.2017.06.021. [DOI] [PubMed] [Google Scholar]
  28. Xu W., Zhu S., Liang Y., Li Z., Cui Z., Yang X., Inoue A.. Nanoporous CuS with excellent photocatalytic property. Sci. Rep. 2016;5:18125. doi: 10.1038/srep18125. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Yang J., Zhang Y., Zeng D., Zhang B., Hassan M., Li P., Qi C., He Y.. Enhanced catalytic activation of photo-Fenton process by Cu0·5Mn0·5Fe2O4 for effective removal of organic contaminants. Chemosphere. 2020;247:125780. doi: 10.1016/j.chemosphere.2019.125780. [DOI] [PubMed] [Google Scholar]
  30. Lee H., Seong J., Lee K.-M., Kim H.-H., Choi J., Kim J.-H., Lee C.. Chloride-enhanced oxidation of organic contaminants by Cu­(II)-catalyzed Fenton-like reaction at neutral pH. J. Hazard. Mater. 2018;344:1174–1180. doi: 10.1016/j.jhazmat.2017.10.020. [DOI] [PubMed] [Google Scholar]
  31. Zhang Q., Liu N., Cao Y., Zhang W., Wei Y., Feng L., Jiang L.. A facile method to prepare dual-functional membrane for efficient oil removal and in situ reversible mercury ions adsorption from wastewater. Appl. Surf. Sci. 2018;434:57–62. doi: 10.1016/j.apsusc.2017.09.230. [DOI] [Google Scholar]
  32. Chen X., Zhang J., Zeng J., Shi Y., Huang G., Zhang L., Wang H., Kong Z., Xi J., Ji Z.. Novel 3D/2D heterojunction photocatalysts constructed by three-dimensional In2S3 dandelions and ultrathin hexagonal SnS2 nanosheets with excellent photocatalytic and photoelectrochemical activities. Appl. Surf. Sci. 2019;463:693–703. doi: 10.1016/j.apsusc.2018.09.013. [DOI] [Google Scholar]
  33. Zhang L., Niu C.-G., Wen X.-J., Guo H., Zhao X.-F., Liang C., Zeng G.-M.. Enhanced photocatalytic activity of CdS/SnS2 nanocomposite with highly-efficient charge transfer and visible light utilization for selective reduction of 4-nitroaniline. J. Colloid Interface. 2018;532:557–570. doi: 10.1016/j.jcis.2018.08.017. [DOI] [PubMed] [Google Scholar]
  34. Das D., Dutta R. K.. A novel method of synthesis of small band gap SnS nanorods and its efficient photocatalytic dye degradation. J. Colloid Interface Sci. 2015;457:339–344. doi: 10.1016/j.jcis.2015.07.002. [DOI] [PubMed] [Google Scholar]
  35. Gnanasekaran L., Hemamalini R., Saravanan R., Ravichandran K., Gracia F., Agarwal S., Gupta V. K.. Synthesis and characterization of metal oxides (CeO2, CuO, NiO, Mn3O4, SnO2 and ZnO) nanoparticles as photocatalysts for degradation of textile dyes. J. Photochem. Photobiol., B. 2017;173:43–49. doi: 10.1016/j.jphotobiol.2017.05.027. [DOI] [PubMed] [Google Scholar]
  36. Krishnan A., Swarnalal A., Das D., Krishnan M., Saji V. S., Shibli S. M. A.. A review on transition metal oxides based photocatalysts for degradation of synthetic organic pollutants. J. Environ. Sci. 2024;139:389–417. doi: 10.1016/j.jes.2023.02.051. [DOI] [PubMed] [Google Scholar]
  37. Imran M., Abutaleb A., Ali M. A., Ahamad T., Ansari A. R., Shariq M., Khan A.. UV light enabled photocatalytic activity of α-Fe2O3 nanoparticles synthesized via phase transformation. Mater. Lett. 2020;258:126748. doi: 10.1016/j.matlet.2019.126748. [DOI] [Google Scholar]
  38. Khan B., Raziq F., Faheem M. B., Farooq M. U., Hussain S., Ali F., Ullah A., Mavlonov A., Zhao Y., Liu Z.. Electronic and nanostructure engineering of bifunctional MoS2 towards exceptional visible-light photocatalytic CO2 reduction and pollutant degradation. J. Hazard. Mater. 2020;381:120972. doi: 10.1016/j.jhazmat.2019.120972. [DOI] [PubMed] [Google Scholar]
  39. Koyyada G., Vattikuti S. P., Shome S., Shim J., Chitturi V., Jung J. H.. Enhanced solar light-driven photocatalytic degradation of pollutants and hydrogen evolution over exfoliated hexagonal WS2 platelets. Mater. Res. Bull. 2019;109:246–254. doi: 10.1016/j.materresbull.2018.09.045. [DOI] [Google Scholar]
  40. Qin N., Wei W., Huang C., Mi L.. An efficient strategy for the fabrication of CuS as a highly excellent and recyclable photocatalyst for the degradation of organic dyes. Catalysts. 2020;10:40. doi: 10.3390/catal10010040. [DOI] [Google Scholar]
  41. Yu W., Guo X., Song C., Zhao Z.. Visible-light-initiated one-pot clean synthesis of nitrone from nitrobenzene and benzyl alcohol over CdS photocatalyst. J. Catal. 2019;370:97–106. doi: 10.1016/j.jcat.2018.12.011. [DOI] [Google Scholar]
  42. Kord M., Hedayati K., Farhadi M.. Green synthesis and characterization of flower-like PbS and metal-doped nanostructures via hydrothermal method. Main Group Met. Chem. 2017;40:35–40. doi: 10.1515/mgmc-2016-0046. [DOI] [Google Scholar]
  43. Dashairya L., Sharma M., Basu S., Saha P.. SnS2/RGO based nanocomposite for efficient photocatalytic degradation of toxic industrial dyes under visible-light irradiation. J. Alloys Compd. 2019;774:625–636. doi: 10.1016/j.jallcom.2018.10.008. [DOI] [Google Scholar]
  44. Deng F., Zhao L., Pei X., Luo X., Luo S.. Facile in situ hydrothermal synthesis of g-C3N4/SnS2 composites with excellent visible-light photocatalytic activity. Mater. Chem. Phys. 2017;189:169–175. doi: 10.1016/j.matchemphys.2016.12.028. [DOI] [Google Scholar]
  45. Zhou X., Soldat A. C., Lind C.. Phase selective synthesis of copper sulfides by non-hydrolytic sol–gel methods. RSC Adv. 2014;4:717–726. doi: 10.1039/C3RA45053H. [DOI] [Google Scholar]
  46. Song X., Sun S., Zhang W., Yin Z.. A method for the synthesis of spherical copper nanoparticles in the organic phase. J. Colloid Interface Sci. 2004;273:463–469. doi: 10.1016/j.jcis.2004.01.019. [DOI] [PubMed] [Google Scholar]
  47. Bano Z., Saeed R. Y., Zhu S., Xia M., Mao S., Lei W., Wang F.. Mesoporous CuS nanospheres decorated rGO aerogel for high photocatalytic activity towards Cr­(VI) and organic pollutants. Chemosphere. 2020;246:125846. doi: 10.1016/j.chemosphere.2020.125846. [DOI] [PubMed] [Google Scholar]
  48. Zhang X., Zhou J., Yang D.-P., Chen S., Huang J., Li Z.. Cu2‑xS loaded diatom nanocomposites as novel photocatalysts for efficient photocatalytic degradation of organic pollutants. Catal. Today. 2019;335:228–235. doi: 10.1016/j.cattod.2018.11.047. [DOI] [Google Scholar]
  49. Lianmawii L., Singh K. B., Singh N. R., Singh N. M.. A review: photocatalytic degradation of dyes by metal sulfide nanoparticles. Braz. J. Chem. Eng. 2025;42:1–30. doi: 10.1007/s43153-023-00425-9. [DOI] [Google Scholar]
  50. Ajibade P. A., Oluwalana A. E.. Enhanced photocatalytic degradation of ternary dyes by copper sulfide nanoparticles. Nanomaterials. 2021;11:2000. doi: 10.3390/nano11082000. [DOI] [PMC free article] [PubMed] [Google Scholar]
  51. Jian F., Wang Z., Bai Z., You X., Fun H. K., Chinnakali K., Razak I. A.. The crystal structure, equilibrium and spectroscopic studies of bis (dialkyldithiocarbamate) copper (II) complexes [Cu2(R2dtc) 4]­(dtc= dithiocarbamate) Polyhedron. 1999;18:3401–3406. doi: 10.1016/S0277-5387(99)00242-9. [DOI] [Google Scholar]
  52. Ferreira I. P., de Lima G. M., Paniago E. B., Takahashi J. A., Krambrock K., Pinheiro C. B., Visentin L. C.. Synthesis, characterization, structural and biological aspects of copper­(II) dithiocarbamate complexes–Part II,[Cu­{S2CN­(Me)­(R1)}2], [Cu­{S2CN (Me)­(R2)}2] and [Cu­{S2CN­(R3)­(R4)}2]­{R1 = CH2CH­(OMe)2], R2 = 2-methyl-1,3-dioxolane, R3 = CH2(CH2)2NCHPhOCH2Ph and R4= CH2CH2OH} J. Mol. Struct. 2013;1048:357–366. doi: 10.1016/j.molstruc.2013.06.006. [DOI] [Google Scholar]
  53. Balakrishnan, S. ; Duraisamy, S. ; Kasi, M. ; Kandasamy, S. ; Sarkar, R. ; Kumarasamy, A. . Syntheses, physicochemical characterization, antibacterial studies on potassium morpholine dithiocarbamate nickel­(II), copper­(II) metal complexes and their ligands. Heliyon, 2019, 5, e01687 10.1016/j.heliyon.2019.e01687. [DOI] [PMC free article] [PubMed] [Google Scholar]
  54. Singh R. P., Singh A., Prasad L. B., Shiv K., Hira S. K., Manna P. P.. Antiproliferative activity of Fe­(II), Co­(II), Ni­(II), Cu­(II), and Zn­(II) complexes of dithiocarbamate: synthesis, structural characterization, and thermal studies. Dalton Trans. 2024;53:1196–1208. doi: 10.1039/D3DT03724J. [DOI] [PubMed] [Google Scholar]
  55. Onwudiwe D. C., Ajibade P. A., Omondi B.. Synthesis, spectra and thermal studies of 2, 2′-bipyridine adducts of bis­(N-alkyl- N-phenyldithiocarbamato)­zinc­(II) J. Mol. Struct. 2011;987:58–66. doi: 10.1016/j.molstruc.2010.11.060. [DOI] [Google Scholar]
  56. Luo S., Zhang S., Yuan H., Wu Z., Li M.. 3D hierarchically branched Cu2S/ZnO heterojunction nanowire arrays for enhanced solar water splitting. Mater. Today Commun. 2023;34:105417. doi: 10.1016/j.mtcomm.2023.105417. [DOI] [Google Scholar]
  57. Panda S., Bariki R., Pradhan S. K., Nayak S. K., Mishra B. G.. Snowflake-like Cu-BDC-NH2/Cu58S32 binary nanohybrid for H2 evolution and O2 reduction. ACS Appl. Nano Mater. 2024;7:7365–7380. doi: 10.1021/acsanm.4c00087. [DOI] [Google Scholar]
  58. Xia C., Pedrazo-Tardajos A., Wang D., Meeldijk J. D., Gerritsen H. C., Bals S., de Mello Donega C.. Seeded growth combined with cation exchange for the synthesis of anisotropic Cu2–xS/ZnS, Cu2–xS, and CuInS2 nanorods. Chem. Mater. 2021;33:102–116. doi: 10.1021/acs.chemmater.0c02817. [DOI] [PMC free article] [PubMed] [Google Scholar]
  59. Li L., Yin N., Jia T., Li P., Zhang W., Zhang W.. Stud-shaped Cu2S nanowire arrays: In situ one-step synthesis and optical properties. J. Electron. Mater. 2025;54:1271–1277. doi: 10.1007/s11664-024-11641-5. [DOI] [Google Scholar]
  60. Liu Y., Liu M., Swihart M.. Reversible crystal phase interconversion between covellite CuS and high chalcocite Cu2S nanocrystals. Chem. Mater. 2017;29:4783–4791. doi: 10.1021/acs.chemmater.7b00579. [DOI] [Google Scholar]
  61. Mbewana-Ntshanka N. G., Moloto M. J., Mubiayi P. K.. Role of the amine and phosphine groups in oleylamine and trioctylphosphine in the synthesis of copper chalcogenide nanoparticles. Heliyon. 2020;6:e05130. doi: 10.1016/j.heliyon.2020.e05130. [DOI] [PMC free article] [PubMed] [Google Scholar]
  62. Abd Elkodous M., El-Sayyad G. S., Abdel Maksoud M. I. A., Abdelrahman I. Y., Mosallam F. M., Gobara M., El-Batal A. I.. Fabrication of ultra-pure anisotropic zinc oxide nanoparticles via simple and cost-effective route: implications for UTI and EAC medications. Biol. Trace Elem. Res. 2020;196:297–317. doi: 10.1007/s12011-019-01894-1. [DOI] [PubMed] [Google Scholar]
  63. Nath S. K., Kalita P.. Effect of capping agents on the optical properties of synthesized CuS nanostructures. Mater. Today Proc. 2017;4:3972–3978. doi: 10.1016/j.matpr.2017.02.297. [DOI] [Google Scholar]
  64. Mnqiwu K., Xaba T., Moloto M., Mubiayi K., Mofokeng T.. Effect of concentration on synthesis of organic passivated Cu2-xS nanoparticles from N-pyrrolidine dithiocarbamate molecular precursor. Asian J. Chem. 2018;30:1978–1982. doi: 10.14233/ajchem.2018.21360. [DOI] [Google Scholar]
  65. Auyoong Y. L., Yap P. L., Huang X., Abd Hamid S. B.. Optimization of reaction parameters in hydrothermal synthesis: a strategy towards the formation of CuS hexagonal plates. Chem. Cent. J. 2013;7:1–12. doi: 10.1186/1752-153X-7-67. [DOI] [PMC free article] [PubMed] [Google Scholar]
  66. Klubnuan S., Suwanboon S., Amornpitoksuk P.. Effects of optical band gap energy, band tail energy and particle shape on photocatalytic activities of different ZnO nanostructures prepared by a hydrothermal method. Opt. Mater. 2016;53:134–141. doi: 10.1016/j.optmat.2016.01.045. [DOI] [Google Scholar]
  67. Arulkumar E., Thanikaikarasan S.. Structure, morphology, composition, optical properties and catalytic activity of nanomaterials CuO, NiO, CuO/NiO using methylene blue. Optik. 2024;302:171685. doi: 10.1016/j.ijleo.2024.171685. [DOI] [Google Scholar]
  68. Botha N. L., Ajibade P. A.. Optical and structural characterization of copper sulphide nanoparticles from copper­(II) piperidine dithiocarbamate. Opt. Quant. Electron. 2020;52(7):337. doi: 10.1007/s11082-020-02455-w. [DOI] [Google Scholar]
  69. Makuła P., Pacia M., Macyk W.. How to correctly determine the band gap energy of modified semiconductor photocatalysts based on UV–Vis spectra. J. Phys. Chem. Lett. 2018;9:6814–6817. doi: 10.1021/acs.jpclett.8b02892. [DOI] [PubMed] [Google Scholar]
  70. Gadore V., Mishra S. R., Ahmaruzzaman M.. Bandgap engineering approach for synthesising photoactive novel Ag/HAp/SnS2 for removing toxic anti-fungal pharmaceutical from aqueous environment. J. Hazard. Mater. 2024;461:132458. doi: 10.1016/j.jhazmat.2023.132458. [DOI] [PubMed] [Google Scholar]
  71. Christy R. S., Kumaran J. T.. Phase transition in CuS nanoparticles. J. Non-Oxide Glas. 2014;6:13–22. [Google Scholar]
  72. Aziz S. B., Abdulwahid R. T., Rsaul H. A., Ahmed H. M.. In situ synthesis of CuS nanoparticle with a distinguishable SPR peak in NIR region. J. Mater. Sci.: Mater. Electron. 2016;27:4163–4171. doi: 10.1007/s10854-016-4278-y. [DOI] [Google Scholar]
  73. Escobar-Sánchez H., Carril Pardo C., Benito N., Hernández-Montelongo J., Nancucheo I., Recio-Sánchez G.. Plasmonic and photothermal effects of CuS nanoparticles biosynthesized from acid mine drainage with potential drug delivery applications. Int. J. Mol. Sci. 2023;24:16489. doi: 10.3390/ijms242216489. [DOI] [PMC free article] [PubMed] [Google Scholar]
  74. Abudllah M., Al Huwayz M., Alwadai N., Manzoor S., Nisa M. U., John P., Ashiq M. N.. Facile fabrication of ternary CuO/CuS/ZnS for photodegradation of methylene blue. J. Korean Ceram. Soc. 2023;60:569–580. doi: 10.1007/s43207-023-00287-4. [DOI] [Google Scholar]
  75. Xiong Q., Shi Q., Gu X., Sheng X., Sun Y., Shi H., Li G.. Visible-light S-scheme heterojunction of copper bismuthate quantum dots decorated Titania-spindles for exceptional tetracycline degradation. J. Colloid Interface Sci. 2024;654:1365–1377. doi: 10.1016/j.jcis.2023.10.141. [DOI] [PubMed] [Google Scholar]
  76. Sathiyaraj E., Thirumaran S.. Structural, morphological and optical properties of iron sulfide, cobalt sulfide, copper sulfide, zinc sulfide and copper-iron sulfide nanoparticles synthesized from single source precursors. Chem. Phys. Lett. 2020;739:136972. doi: 10.1016/j.cplett.2019.136972. [DOI] [Google Scholar]
  77. Tetyana P., Mphuthi N., Jijana A. N., Moloto N., Shumbula P. M., Skepu A., Sikhwivhilu L.. Synthesis, characterization, and electrochemical evaluation of copper sulfide nanoparticles and their application for non-enzymatic glucose detection in blood samples. Nanomaterials. 2023;13:481. doi: 10.3390/nano13030481. [DOI] [PMC free article] [PubMed] [Google Scholar]
  78. Roy P., Srivastava S. K.. Hydrothermal growth of CuS nanowires from Cu– dithiooxamide, a novel single-source precursor. Cryst. Growth Des. 2006;6:1921–1926. doi: 10.1021/cg060134+. [DOI] [Google Scholar]
  79. Kapuria N., Imtiaz S., Sankaran A., Geaney H., Kennedy T., Singh S., Ryan K. M.. Multipod Bi­(Cu2‑xS)­n nanocrystals formed by dynamic cation–ligand complexation and their use as anodes for potassium-ion batteries. Nano Lett. 2022;22:10120–10127. doi: 10.1021/acs.nanolett.2c03933. [DOI] [PMC free article] [PubMed] [Google Scholar]
  80. Ain N. u., Zia-ur-Rehman, Aamir A., Khan Y., Rehman M.-u., Lin D.-J.. Catalytic and photocatalytic efficacy of hexagonal CuS nanoplates derived from copper­(II) dithiocarbamate. Mater. Chem. Phys. 2020;242:122408. doi: 10.1016/j.matchemphys.2019.122408. [DOI] [Google Scholar]
  81. Liu Y., Liu H., Zhang Q., Li T.. Adjusting the proportions of {0001} facets and high-index facets of ZnO hexagonal prisms and their photocatalytic activity. RSC Adv. 2017;7:3515–3520. doi: 10.1039/C6RA24912D. [DOI] [Google Scholar]
  82. Adhikari S., Sarkar D., Madras G.. Hierarchical design of CuS architectures for visible light photocatalysis of 4-chlorophenol. ACS Omega. 2017;2:4009–4021. doi: 10.1021/acsomega.7b00669. [DOI] [PMC free article] [PubMed] [Google Scholar]
  83. Li L., Wang Y.-h., Li H., Huang H.-j., Zhao H.. Suppression of photocatalysis and long-lasting luminescence in ZnGa2O4 by Cr3+ doping. RSC Adv. 2015;5:57193–57200. doi: 10.1039/C5RA09175F. [DOI] [Google Scholar]
  84. Wang Z., Xiao M., You J., Liu G., Wang L.. Defect engineering in photocatalysts and photoelectrodes: From small to big. Acc. Mater. Res. 2022;3:1127–1136. doi: 10.1021/accountsmr.1c00201. [DOI] [Google Scholar]
  85. Mahmoodi N. M., Arami M., Limaee N. Y., Tabrizi N. S.. Kinetics of heterogeneous photocatalytic degradation of reactive dyes in an immobilized TiO2 photocatalytic reactor. J. Colloid Interface Sci. 2006;295:159–164. doi: 10.1016/j.jcis.2005.08.007. [DOI] [PubMed] [Google Scholar]
  86. Abbasi_Asl H., Moradi Z., Ghaedi M., Sabzehmeidani M. M.. Degradation of Orange G and Trypan blue using Ag2C2O4/Ag/g-C3N4 composites as efficient photocatalyst under solar irradiation. J. Photochem. Photobiol, A. 2020;401:112755. doi: 10.1016/j.jphotochem.2020.112755. [DOI] [Google Scholar]
  87. Ghiasi E., Malekzadeh A.. Removal of various textile dyes using LaMn­(Fe)­O3 and LaFeMn0.5O3 nanoperovskites; RSM optimization, isotherms and kinetics studies. J. Inorg. Organomet. Polym. 2020;30:2789–2804. doi: 10.1007/s10904-019-01438-z. [DOI] [Google Scholar]
  88. Palharim P. H., Caira M. C. D. A., de Araújo Gusmão C., Ramos B., dos Santos G. T., Rodrigues O. Jr, Teixeira A. C. S. C.. Effect of temperature and time on the hydrothermal synthesis of WO3-AgCl photocatalysts regarding photocatalytic activity. Chem. Eng. Res. Des. 2022;188:935–953. doi: 10.1016/j.cherd.2022.10.045. [DOI] [Google Scholar]
  89. Alazmi A.. Surfactant assisted hydrothermal synthesis of graphene reinforced nanoferrite: A novel nanocomposite for photocatalytic abatement of azo dye. Surf. Interface. 2025;56:105731. doi: 10.1016/j.surfin.2024.105731. [DOI] [Google Scholar]
  90. Ren G., Zhang J., Li S., Zhang L., Shao C., Wang X., Bai H.. Z-scheme heterojunction composed of Fe-doped g-C3N4 and Bi2MoO6 for photo-fenton degradation of antibiotics over a wide pH range: Activity and toxicity assessment. Environ. Res. 2024;252:118886. doi: 10.1016/j.envres.2024.118886. [DOI] [PubMed] [Google Scholar]
  91. Mbese J. Z., Ajibade P. A.. Synthesis, structural and optical properties of ZnS, CdS and HgS nanoparticles from dithiocarbamato single molecules precursors. J. Sulfur Chem. 2014;35(4):438–449. doi: 10.1080/17415993.2014.912280. [DOI] [Google Scholar]
  92. Dolomanov O. V., Bourhis L. J., Gildea R. J., Howard J. A., Puschmann H.. OLEX2: a complete structure solution, refinement and analysis program. J. Appl. Crystallogr. 2009;42:339–341. doi: 10.1107/S0021889808042726. [DOI] [Google Scholar]
  93. Sheldrick, G. M. SHELXL-2018 Program for crystal structure refinement; Universität Göttingen: Göttingen, Germany, 2018. [Google Scholar]
  94. Sheldrick G. M.. Crystal structure refinement with SHELXL. Acta Crystallogr. 2015;A71:3–8. doi: 10.1107/S2053229614024218. [DOI] [PMC free article] [PubMed] [Google Scholar]
  95. Mahboob I., Shafiq I., Shafique S., Akhter P., Amjad U.-e.-S., Hussain M., Park Y.-K.. Effect of active species scavengers in photocatalytic desulfurization of hydrocracker diesel using mesoporous Ag3VO4 . Chem. Eng. J. 2022;441:136063. doi: 10.1016/j.cej.2022.136063. [DOI] [Google Scholar]

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