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. 2025 Dec 26;11(1):2074–2083. doi: 10.1021/acsomega.5c10669

Preparation and Performance Study of Superhydrophobic Bamboo Surface with TiO2‑Based Nanocomposite Coatings

Jiayu Yang †, Gentao Zhang †,*, Xiaorong Zheng †, Xinde Bao ‡, Huakang Zhou †, Guofu Wu †, Yinluan Qin †
PMCID: PMC12809347  PMID: 41552534

Abstract

To enhance the surface superhydrophobic performance of bamboo, this study employed 1H,1H,2H,2H-perfluorodecyltrimethoxysilane to fluorinate TiO2 nanoparticles, and successfully prepared a superhydrophobic bamboo surface. The results showed that the water contact angle of the modified superhydrophobic bamboo surface exceeded 160°, and it also exhibited excellent wear resistance, self-cleaning property, chemical stability, and ultraviolet resistance. This research provides a theoretical basis for the application of bamboo in fields such as construction and outdoor decoration.

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1. Introduction

Bamboo boasts benefits like a brief growth period, high productivity, and low cost. It shows good application potential in many fields. However, as a woody fiber material, bamboo contains abundant components like cellulose, hemicellulose, and lignin. , These components contain numerous hydrophilic hydroxyl groups. In addition, bamboo itself features an abundant capillary structure. This causes bamboo to easily absorb moisture from the air. It further leads to problems such as cracking, mildew, and even decay. These issues seriously affect its performance and service life. Therefore, to fundamentally prevent water from penetrating into bamboo, effectively delay its degradation, and significantly extend its service life, hydrophobic modification of bamboo is of great practical significance and necessity.

The fundamental principle behind superhydrophobic treatment technology involves building micro- or nanoscale rough structures on the material surface, along with modifying it using substances with low surface energy. This gives rise to a contact angle exceeding 150° between the material surface and water, while the rolling angle measures less than 10°. This property makes water droplets hardly wet the surface. It shows a “water-repellent” effect similar to the surface of lotus leaves. Such superhydrophobic surfaces can not only efficiently block water molecules from penetrating into materials but also have multiple characteristics like self-cleaning, corrosion resistance, and ice prevention. − Thus, they are widely used in various fields. Currently, common methods for preparing superhydrophobic surfaces include chemical vapor deposition, sol–gel, template, and spray methods. −

In recent years, a large number of scholars have investigated how to synthesize superhydrophobic coatings on the surfaces of bamboo and wood materials. Gao et al. utilized fresh lotus leaves as templates alongside polydimethylsiloxane, successfully constructing a lotus-leaf-mimicking surface on modified bamboo through soft lithography. Property evaluations of the treated bamboo revealed a marked enhancement in its hydrophobic performance, thereby establishing a groundwork for investigations into bamboo’s dimensional stability and the mechanisms underlying hydrophobic modification. Chen et al. combined hydrothermal synthesis with polymethylhydrosiloxane (PMHS)-based hydrophobic modification to develop ZnO/PMHS composite coatings on bamboo surfaces, demonstrated not only a significant improvement in hydrophobicity but also a notable boost in mildew resistance. Irvani et al. sought to examine how chemical modification impacts the improvement of hydrophobicity and thermal stability in bamboo fibers. Bamboo fibers were subjected to modification via stearic acid coating combined with aluminum hydroxide nanoparticles. The findings indicated that stearic acid (STA) had a good effect on improving the hydrophobicity of bamboo fibers. Wang et al. intended to solve the problem that traditional hydrophobic coatings cannot endow the internal structure of bamboo with superhydrophobicity. They prepared full-surface hydrophobic bamboo through technologies such as liquid deposition, hot pressing and surface spraying. The results showed that the water contact angle of the outer surface was 161.16°, that of the inner surface was 135.47°, and the sliding angle of the outer surface was only 8°. Cao et al. connected TiO2 nanoparticles with fluorinated siloxane through Ti–O–Si bonds to form a nanocomposite (Si-PFE-TiO2). They used this composite to modify the surface of stone materials, obtaining superhydrophobic properties. The stone surface thus gained photocatalytic and antibacterial characteristics. Liu et al. prepared superhydrophobic surfaces on both soft and hard wood. The modified wood not only had self-cleaning function, and wear resistance. It also had long-lasting ultraviolet resistance, which greatly extended the service life of the wood. Wang et al. fabricated a honeycomb-shaped superhydrophobic coating via a spraying technique. This coating possessed outstanding self-cleaning characteristics, wear resistance and ultraviolet resistance. Liu et al. mixed a composite of TiO2 particles and MWCNTs with an epoxy resin matrix. This mixture was then sprayed onto a substrate to fabricate a superhydrophobic surface, which exhibited exceptional wear resistance and deicing capabilities. Wang et al. applied nanozinc oxide/polydimethylsiloxane (PDMS) to modify fast-growing poplar wood veneers. This modification facilitated the deposition of a zinc oxide film, endowing the wood with good hydrophobicity. It effectively enhanced the antiphotochromic performance of the wood surface. Zhang et al. modified TiO2–SiO2 composite particles with PFDTS. The suspension was applied to the substrate surface to fabricate a superhydrophobic coating, whose surface exhibited excellent superhydrophobic properties. Su et al. proposed a bifunctional self-cleaning film. This film was derived from modifying PFDTS with PDMS nanopillar arrays and TiO2 nanoparticles. This film could degrade organic pollutants. It also had superhydrophobicity and good mechanical properties. He et al. fluorinated PDMS with a fluorinating agent. They then used a spraying method to deposit a composite coating on the surface of PET fabric. This produced a superhydrophobic and flame-retardant coated fabric. The findings indicated that the coated fabric displayed favorable superhydrophobicity, self-cleaning capability, and superior mechanical durability. Zhang et al. systematically outlined the unique advantages and recent advances of metal oxides in constructing sustainable superhydrophobic surfaces. Their study demonstrated that metal oxides surpass the limitations of conventional materials. This is due to their tunable electronic structures, inherent thermal/chemical stability, and abundant natural reserves. Metal oxides provide a new platform for high-performance and environmentally friendly superhydrophobic technologies. Chen et al. proposed various innovative strategies aimed at the problem of poor durability in superhydrophobic surfaces for protecting architectural and stone cultural heritage. For future needs, they pointed out that developing superhydrophobic systems with environmental friendliness, high transparency, long-term durability, and a simple preparation process is an important research direction. Refaee et al. prepared a ternary nanobiocomposite (PPCH-TiO2–Ag) by combining TiO2 and Ag nanoparticles with a novel biopolymer, polyphosphonium chitosan hydrazone (PPCH). They used this composite to functionalize cotton fabric. The modified fabric exhibited excellent superhydrophobicity. It also demonstrated strong antibacterial and anti-UV properties, along with good durability. This work provides a promising strategy for developing safe and efficient multifunctional textiles. Li et al. applied a hydrophobically modified nano-TiO2 coating to a lignocellulose paper, creating a flexible smart material. The surface of this material could reversibly switch between superhydrophobicity and superhydrophilicity upon UV irradiation and heating. It exhibited excellent reversible cycling stability.

Nano-TiO2 is a highly promising inorganic functional semiconductor photocatalytic material. It has significant advantages such as low cost, high safety and stable chemical properties. It shows broad application prospects in multiple fields. However, it has certain defects. Due to its high surface energy, it tends to agglomerate in practical applications. It also has poor compatibility with organic materials. These problems limit the full exertion of its performance. Therefore, surface modification of TiO2 nanoparticles to improve its comprehensive performance and application effect has important practical significance. In this study, in order to prepare a superhydrophobic surface on bamboo, PFDTMS was used to reduce the surface energy of TiO2 particles. Then methyl methacrylate was added to fully dissolve the substance. Finally, epoxy resin was used to increase the surface adhesion of the substance. An ultrahydrophobic coating was obtained eventually.

2. Experimental Section

2.1. Materials

Bamboo samples were 10 mm × 10 mm × 3 mm (length× width× thickness). They were sourced from Guangxi Gao Feng Forest Farm. Their moisture content ranged from 10% to 12%.

Anhydrous ethanol (99.7%), titanium dioxide (TiO2), 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PFDTMS), methyl methacrylate, benzoyl peroxide, ethyl acetate, epoxy resin, and epoxy resin curing agent. All were purchased from Shanghai Enke Chemical Technology Co., Ltd.

2.2. Methods

2.2.1. Bamboo Pretreatment

The surface of bamboo samples was polished smooth with 1500-mesh sandpaper. Then the bamboo was placed in an ultrasonic cleaner (DR-MS20, Shenzhen Derui Ultrasonic Equipment Co., Ltd.). The bamboo samples were ultrasonically cleaned with deionized water for 30 min. After cleaning, the bamboo was put into a blast dryer (101–00BS, Shanghai Xinieniu Laibo Instrument Co., Ltd.) at 60 °C to dry for 6 h to removed moisture from the bamboo.

2.2.2. Preparation of Fluorinated TiO2 Particles

1g of TiO2 nanoparticles was dissolved in 10 mL of anhydrous ethanol. After stirring evenly, 0.3 g of PFDTMS was added. After stirring and mixing, the mixture was transferred to the reaction vessel of a magnetic stirrer (WS-2A, Changzhou Yuexin Instrument Manufacturing Co., Ltd.). The mixture was stirred at a constant temperature of 45 °C for 3 h. Fluorinated TiO2 particles were obtained after the reaction.

2.2.3. Preparation of Fluorinated TiO2/Methyl Methacrylate Composite Sol

Fluorinated TiO2 particles were added to a mixed solution containing 0.068 g of methyl methacrylate, 0.038 g of benzoyl peroxide, and 5 mL of ethyl acetate. The mixture underwent magnetic stirring at 45 °C for 2 h. Fluorinated TiO2/methyl methacrylate composite sol was obtained.

2.2.4. Bamboo Surface Coating Treatment

Epoxy resin and its curing agent were blended uniformly in a 3:1 ratio to prepare an epoxy resin mixture. Subsequently, this mixture was evenly spread onto the surface of pretreated bamboo. After the surface of the epoxy resin mixture was slightly cured, the prepared fluorinated TiO2/methyl methacrylate superhydrophobic coating was evenly applied on its surface. The surface modification of bamboo was completed. The preparation process flowchart of fluorinated TiO2/methyl methacrylate superhydrophobic coating is shown in Figure .

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Flowchart of preparation process for fluorinated TiO2/methyl methacrylate superhydrophobic coating.

2.3. Characterization

2.3.1. FTIR

A Fourier transform infrared spectrometer (Nicolet iN10, Thermo Fisher Scientific, USA) was used. Its resolution was 4 cm–1, with the number of scans set at 32. The functional groups on the surface of the superhydrophobic coating and the TiO2–PFDTMS and epoxy resin mixture were analyzed in the wavenumber range of 400–4000 cm–1.

2.3.2. SEM

Bamboo samples were sliced into 10 mm × 10 mm × 3 mm blocks using a blade. Then the samples were sputter-coated with gold in a vacuum environment. The sputtering current was 10 mA.

2.3.3. XPS

Chemical elements on the bamboo surface and their relative contents were analyzed using an X-ray photoelectron spectrometer (K-α, Thermo Scientific, USA). The excitation source employed was an Al Kα ray (hv = 1486.6 eV). The spot dimension was set to 400 μm, with the operating voltage maintained at 12 kV and the filament current at 6 mA. The electron emission angle was 60°.

2.3.4. TG

To investigate the influence of the epoxy resin on the thermal stability of the hydrophobic coating, thermogravimetric was performed using a thermogravimetric analyzer (Netzsch, Germany). The following two samples were heated from 30 to 800 °C under a nitrogen atmosphere at a heating rate of 10 °C/min. Sample A: An epoxy resin primer was applied to the bamboo surface. The fluorinated TiO2/methyl methacrylate composite sol was then coated on top. Sample B: The fluorinated TiO2/methyl methacrylate composite sol was directly coated onto the bamboo surface.

2.3.5. AFM

The surface roughness of the coatings was analyzed using an atomic force microscope (Bruker Dimension Icon, Germany). The superhydrophobic coating were scanned to obtain their three-dimensional topography. The scanning area was 3  μm × 3 μm.

2.4. Wettability Test

The wettability of a material is evaluated based on the contact angle that forms between a liquid and the bamboo surface. For testing the wettability of the samples, a contact angle meter (SDC-200, Sindin, Dongguan, China) was utilized to determine the contact angle on the sample surface. The water droplets used for measurement had a volume of 5 μL. At room temperature, measurements were taken at 5 separate locations on the surface of each sample, and the average of these readings was used as the contact angle for the sample.

2.5. Antifouling Performance Test

Superhydrophobic materials usually have good self-cleaning and antifouling abilities due to their surface hydrophobicity. To test the antifouling performance of the fluorinated TiO2/methyl methacrylate superhydrophobic coating, different types of contaminants such as wood chips, carbon powder, and flour were evenly sprinkled on the coating surface. Water droplets were dripped above the contaminated bamboo. The entire process of water droplet rolling was recorded. The removal effect of the coating on contaminants was observed.

2.6. Wear Resistance Test

Mechanical wear resistance of superhydrophobic coating and uncoated bamboo surface was tested via sandpaper abrasion. A 5 mm × 5 mm sample of the superhydrophobic coating was positioned on 1000# sandpaper, with the coating side facing inward. A 100 g weight was loaded on the coating to apply constant pressure. During the test, a horizontal pull was applied to the sample. It was moved 10 cm forward along the ruler and then 10 cm backward. This back-and-forth process was defined as one abrasion cycle. After each abrasion cycle, the contact angle on the bamboo surface was measured using a contact angle meter.

2.7. Chemical Resistance

The chemical tolerance of this superhydrophobic coating was evaluated by immersing it in hydrochloric acid solution (pH = 2) and sodium hydroxide solution (pH = 12), and taking samples every 2 h to measure the contact angle and sliding angle of the coating.

2.8. Tape Peeling Test

The adhesion strength between the superhydrophobic coating and the bamboo substrate was evaluated using a tape peeling test. Electrical tape was firmly applied to the coating surface, ensuring no air bubbles were trapped between the tape and the coating. The tape was then rapidly peeled off by hand from one end. This procedure was defined as one peeling cycle.

2.9. UV Resistance Test

The bamboo sample coated with the superhydrophobic layer was exposed to UV light (40 W, 340 nm). The sample was removed every 5 h to measure its water contact angle and sliding angle.

3. Results and Discussion

3.1. SEM Morphology

To evaluate the construction effect of the superhydrophobic coating, the surface of pristine bamboo without any coating was first examined by scanning electron microscopy (SEM). As shown in Figure a, the surface of the pristine bamboo exhibits the natural fibrous vessel structure and cell wall morphology of bamboo, which is the fundamental reason for its inherent hydrophilicity. As shown in Figure b, using 1500-mesh sandpaper, the surface of the bamboo was polished 30 times, the fibers on the bamboo surface became blurred, and the abrasion resulted in a smoother surface. This indicates that the polished bamboo surface is more amenable to the application of a hydrophobic coating.

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SEM micromorphology of bamboo Surface. (a) Microscopic image of bamboo before sanding; (b)­Microscopic images of the bamboo after polishing.

As shown in Figure a–c, these are SEM images depicting the surface of the hydrophobic coating under varying magnifications. It can be clearly observed from Figure a that the coating surface is covered with micron-scale rough structures. At higher magnification (Figure b), it can be observed that these rough structures are formed by the uniform and random distribution of a large number of nanoparticles on the bamboo surface, and the random arrangement of nanoparticles creates many gaps, which significantly increases the surface roughness of the bamboo. Figure c shows that the TiO2 nanoparticles are wrapped by hydrophobic substances. The incorporation of fluorosilane effectively lowers the surface energy of bamboo, causing water droplets and the coating to form a natural air cushion. This significantly decreases their contact area, thereby granting the coating superhydrophobic characteristics. As illustrated in Figure d–j, these are the EDS element distribution maps of the hydrophobic coating surface. The analysis results regarding the chemical composition of the superhydrophobic coating indicate that nanoparticles containing C, O, F, Si, and Ti elements are evenly dispersed across the superhydrophobic surface. The presence of F and Si elements indicates that the fluorinating agent has successfully combined with TiO2 nanoparticles. This combination effectively reduces the surface energy of TiO2, which is an important reason for the superhydrophobicity of the coating.

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SEM micromorphology of hydrophobic coating: (a–c) SEM images; (d–j) EDS element maps.

3.2. Chemical Structure Analysis

As shown in Figure a, it presents the FTIR spectra of TiO2 nanoparticles and fluorinated TiO2/methyl methacrylate nanoparticles. A characteristic peak at 3442 cm–1 is linked to the stretching and bending vibrations of −OH groups. A comparison reveals that the intensity of the characteristic peak at 3442 cm–1 in the modified TiO2 nanoparticles is significantly reduced, indicating incomplete condensation of the inorganic component (Ti–OH). A characteristic peak at 1723 cm–1 arises from the stretching vibration of the CO bond within the methyl methacrylate side group (−COOCH3). The characteristic peaks at 1555 and 1675 cm–1 are linked to the stretching vibrations of C–F bonds in the CF2 and CF3 groups of PFDTMS, which suggests that fluorine has been successfully loaded onto the surface of titanium dioxide. The characteristic peak at 1059 cm–1 corresponds to the stretching vibration of the Si–O–Si bond.

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Superhydrophobic layer properties. (a) FTIR of TiO2 and fluorinated TiO2/methyl methacrylate particles; (b) full XPS spectrum, (c) C1s narrow spectrum, (d) O1s narrow spectrum, (e) F1s narrow spectrum, and (f) Ti2p narrow spectrum.

The chemical composition of the object surface has an important impact on its wetting performance. Figure shows the XPS survey and narrow-scan spectra of the fluorinated TiO2/methyl methacrylate superhydrophobic coating. The survey spectrum (Figure b) shows characteristic peaks of F1s, C1s, O1s, Si2p, and Ti2p. This finding is consistent with the previous EDS elemental analysis (Figure ). It provides further proof that F and Si elements were successfully introduced to the coating surface. In the C1s spectrum (Figure c), the significant peaks at 291.8 and 284.8 eV are assigned to CF2 and C–C/C-H, respectively. Additionally observed were peaks for the Si–O–C and CF3 bonds at 286.5 and 294.1 eV, respectively, with slightly lower intensities. The O1s spectrum (Figure d) exhibits peaks at 533.0 and 530.5 eV, assigned to -O-Si and TiO2 bonds, respectively. A prominent peak identified in the high-resolution F1s spectrum (Figure e) at a binding energy of 688.8 eV is ascribed to CF2 and CF3 species. Analysis of the Ti2p narrow scan (Figure f) reveals two peaks located at 465.1 and 459.3 eV. These are assigned to the Ti 2p1/2 and Ti 2p3/2 orbitals, respectively, which is consistent with literature reports.

Figure a shows the FTIR spectrum of the TiO2–PFDTMS/epoxy resin mixture. The characteristic peak at 418 cm–1 originates from the vibration of the Ti–O–Ti bond, indicating the presence of TiO2. The peaks at 1038 cm–1 and 1001 cm–1 are attributed to the stretching vibrations of Si–O–Si bonds. The peaks at 1226 cm–1 and 1143 cm–1 correspond to C–F bond stretching vibrations. Characteristic peaks at 2952 cm–1, 1760 cm–1, and 1597 cm–1 arise from CC skeletal vibrations, confirming the presence of epoxy resin.

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Properties of TiO2–PFDTMS/Epoxy Resin Mixture (a)­FTIR; (b)­TGA;(c) DTG.

3.3. Thermogravimetric Analysis

Figure b shows the TGA curves of sample mass change versus temperature. Sample A with the epoxy resin primer had a higher residual mass (27.59%) at 800 °C than Sample B without the epoxy resin (26.24%). The results demonstrate that the coating with an epoxy resin interlayer had a higher residual mass after thermal decomposition than the coating without epoxy. Figure c shows the DTG curves of the samples. Sample B exhibited a distinct decomposition peak at 360.6 °C, with a mass loss rate of −7.92 %/min. In contrast, Sample A showed a peak at 359.4 °C, with a mass loss rate of −6.77 %/min. Furthermore, Sample B displayed a major decomposition peak at 74.4 °C, while Sample A exhibited a peak at 75.9 °C. This confirms that the epoxy resin not only improved adhesion between the hydrophobic coating and the bamboo substrate but also enhanced the thermal stability of the coating system.

3.4. AFM Three-Dimensional Surface Morphology and Roughness Analysis

Figure presents the AFM image of the Superhydrophobic Coating Surface. The coating surface exhibits a protruding nanorough structure. The measured surface roughness values are Ra = 104 nm and Rq = 131 nm. This moderate nanoscale roughness is crucial for achieving superhydrophobicity.

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AFM Image of the superhydrophobic coating surface.

3.5. Antifouling Performance Test

Figure shows the scene where water droplets fall on the modified coating surface covered with contaminants. The results show that when water droplets roll off, they can carry away contaminants such as Figure (a) wood chips, (b) carbon powder, and (c) flour on the surface, while the modified bamboo surface remains clean and dry without any residual contaminants. This phenomenon intuitively reflects that the modified coating possesses excellent self-cleaning capability. Surface contaminants can be efficiently removed by the rolling of water droplets, with the substrate material remaining clean and dry.

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Contaminants rolling off from the coating surface. (a) Wood chips, (b) Carbon powder and (c) Flour.

3.6. Wear Resistance Test

Figure a presents the curves illustrating how the contact angle and rolling angle of the coating surface change with the number of wear cycles. As observed from the figure, when the wear cycle count is fewer than 25, the coating surface demonstrates superior superhydrophobic properties, and the water contact angle stays above 150° consistently. However, once the wear cycle count goes beyond 25, the coating begins to degrade, the contact angle decreases sharply, and the coating gradually loses its superhydrophobic performance. When the wear cycle count reaches 30, the static water contact angle drops to 123°, and the rolling angle rises to 15°, so the coating surface completely loses its superhydrophobicity. Figure b shows the SEM image of the hydrophobic surface after abrasion. It can be observed that nanoparticles in some areas have been worn away. and bamboo fibers are exposed, so these areas no longer have superhydrophobicity. Nanoparticles in some areas still exist, which is the key reason why the coating can still maintain partial hydrophobicity after wear.

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Sandpaper wear test (a) Effect of sandpaper wear cycles on contact angle and rolling angle of the coating surface. (b) SEM image of the hydrophobic surface after abrasion.

3.7. Chemical Resistance Analysis

The experimental results are shown in Figure . After immersing the superhydrophobic coating in acidic and alkaline conditions for 10 and 6 h, respectively, it could still maintain a water contact angle greater than 150° and a sliding angle less than 10°, which indicates that it possesses excellent chemical stability. Among the results, it is shown that the coating is more susceptible to damage in an alkaline environment; however, bamboo is more often exposed to acidic environments (e.g., acid rain). Therefore, this superhydrophobic coating provides a favorable guarantee for the application of bamboo in outdoor and other related fields.

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Chemical resistance rest (a) coating acid resistance test; (b) coating alkali resistance test

3.8. Tape Peeling Test

After conducting the tape peel test, the contact angle and sliding angle of the superhydrophobic coating surface were measured. As shown in Figure a, even after 50 peel cycles, the coating could still maintain a contact angle greater than 150° and a sliding angle less than 10°. These results indicate that this superhydrophobic coating exhibits excellent mechanical stability on the bamboo substrate. However, when the number of peel cycles increased to 70, the contact angle of the coating surface decreased to 143°, while the sliding angle increased to 14°. This phenomenon is attributed to the damage of the micronano rough structure on the coating surface during the tape peel process.

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Tape peeling test and UV resistance test (a) effects of tape peeling on the contact angle and sliding angle of superhydrophobic coatings; (b) effects of UV radiation on the contact angle and sliding angle of superhydrophobic coatings.

3.9. UV Resistance Test

The UV resistance of the superhydrophobic coating was evaluated via accelerated aging tests, with the experimental results shown in Figure b. the coated bamboo sample maintained superhydrophobicity after 20 h of irradiation, demonstrating the coating’s good UV resistance.

3.10. Mechanism of Action

Figure is a schematic diagram of the chemical reaction mechanism. Due to the high surface energy of TiO2 particles, PFDTMS with a lower surface energy is used to modify the surface of the nano TiO2 particles. Figure a shows that PFDTMS dissolves in water and undergoes a hydrolysis reaction, generating silanol and methanol. Figure b indicates that the titanium hydroxyl groups and silanol on the TiO2 surface undergo dehydration condensation reactions. Introducing fluorine groups on the surface of TiO2 can effectively reduce the surface energy and give it hydrophobicity. Figure c shows that the addition of epoxy resin can enhance the bonding force between the hydrophobic coating and the bamboo substrate, reduce the coating wear during use, and extend its service life.

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Diagram of chemical reaction mechanism.

4. Conclusions

In this study, 1H,1H,2H,2H-perfluorooctyltrimethoxysilane was employed as a modifier to functionalize the surface of TiO2 nanoparticles, thereby fabricating a fluorine-containing TiO2 superhydrophobic coating. The experimental results show that the water contact angle of the prepared superhydrophobic coating exceeds 160° and a sliding angle of 3°. Antifouling performance tests indicated that the surface possessed remarkable self-cleaning effects. After undergoing 25 cycles of sandpaper abrasion and 50 cycles of tape peeling tests, the coating still retained its superhydrophobicity, indicating excellent mechanical stability. When immersed in acidic and alkaline environments for 10 and 6 h, respectively, the water contact angle of the superhydrophobic coating remained greater than 150° with a sliding angle less than 10°, demonstrating outstanding chemical stability. Moreover, the bamboo samples coated with this coating maintained superhydrophobicity after 20 h of UV irradiation, suggesting good UV resistance of the coating. Overall, this coating holds broad practical application prospects in bamboo protection, outdoor building materials, and other related fields.

Acknowledgments

The authors are grateful to the funding supported by Guangxi Forestry Science and Technology Promotion Project(2025GXZCLK70)and Guangxi Universities Young and Middle-aged Teachers’ Research Basic Capability Enhancement Project(2024KY1275).

J.Y.: writingoriginal draft and experimental operation. G.Z.: funding acquisition. X.Z.: writingreview and editing. X.B.: data curation and experimental operation. H.Z.: methodology. G.W.: investigation. Y.Q.: Project administration.

The authors declare no competing financial interest.

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