Table 2.
Performance of the current works's photodegradation in comparison to other published studies.
| Dye compound | Photo catalyst | Photocatalyst dose | Synthesis technique | Synthesis reagents and reaction conditions | Doping conc. | Catalyst surface area, (m2/g) | Modified bandgap, and λ value | Particle size, nm | Light source | Experimental conditions | Illumination time, min | Photodegradation efficiency, % | Ref. |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Methylene blue | Cu/ZnO | 3 g/L | Precipitation method | Cu(CH3COO), ZnC4H6O4, calcined at 600 °C for 2 h. | 1.08 mol% | 6.6 | 2.92 eV, (300–900 nm) | 32–33 | 10 W Visible LED strip | pH: 7.0, dye vol.: 100 mL, dye conc.,: 10.0 mg L−1 | 120 | 52.0 | [51] |
| Acid Blue 1 | Ni/ZnO | 1.07 g/L | Sol-gel method | (Ni (NO3)2⋅6H2O), (Zn (CH3COO)2⋅2H2O), the gel was dried at 80 °C for 18 h. | 1.12 wt% | N/A | 2.97 eV, (368 nm) | 19.19–24.79 | 6 W Hg lamp | pH: 7.77, dye vol.: 100 mL, dye conc.,: 10.0 mg L−1 | 180 | 90.23 | [4] |
| Methylene blue | Cu/ZnO | 5–20 g/L | Chemical growth method | (Cu (OAc))2, (ZnC4H6O4), the solution was kept in oven at 95 °C for 6 h. | 1.00 wt% | N/A | 3.46–3.10 eV, (250–600 nm) | N/A | 10 W UV lamp | pH: 6.79, dye vol.: 100 mL, dye conc.,: 10.0 mg L−1 | 180 | 60.0 | [65] |
| Methylene blue | Ni/ZnO | 0.2 g/L | Precipitation method | (Ni(NO3)2·6H2O), (Zn(NO3)2·6H2O), calcining the precursor at 500 °C for 2 h in air. | 5.0 mol% | 8.12 | N/A, (365 nm) | 20.0–30.0 | 300 W Hg lamp | pH: 6.8, dye vol.: 50 mL, dye conc.,: 10.0 mg L−1 | 60 | 98.0 | [61] |
| Indigo carmine | Ni/ZnO | 0.02 g/L | Electrochemical method | (Ni(NO3)2·6H2O), NaHCO3, calcined at 500 °C for 2 h. | 0.5 wt% | 10.0 | 3.1 eV (340 nm) | 78.3 | UV light | pH: 10.0, dye vol.: N/A, dye conc.,: N/A | 90 | 84.84 | [56] |
| Methyl orange | Cu/ZnO | 0.1 g/L | One-step hydrothermal method | ZnSO4, and CuSO4 were the precursor, and the mixture underwent a 4 h hydrothermal treatment at 180 °C. | 1.0 wt% | N/A | (350–400 nm) | 30–150 | Sunlight illumination | pH: N/A, dye vol.: 50 mL, dye conc.,: N/A | 200 | 88.0 | [37] |
| Methylene blue | Cu/ZnO | 0.025 g/L | Co-precipitation method | (Zn (CH3COO)2⋅2H2O),and (Cu(CH3COO)2·H2O) were taken as precursor, and annealing at 600 °C for 3 h. | 5.0 wt% | N/A | 3.48 eV (356–364 nm) | 19.60–132.02 | UV light illumination | N/A | 60 | 72.13 | [30] |
| Methyl orange | Ni/ZnO | 0.210 g/L | Sol-gel method | (Ni(NO3)2·6H2O), ((CH3COO)2Zn·2H2O), annealed at 400° for 1 h in a muffle furnace. | 2.0 wt% | N/A | 3.44–3.16 eV, (350–400 nm) | 12.91–8.84 nm | 80 W UV lamp | pH: 12.0, dye vol.: 120 mL, dye conc.,: 10.0 mg L−1 | 180 | 94.47 | Present work |