Visible-Light-Driven Photocatalytic Activity of Ag-Loaded TiO₂ Nanoparticulate Thin Film Fabricated via PECVD-PVD Method

Figures & data

Figure 1. TiO₂-Ag photocatalytic mechanism for the degradation of organic pollutants under visible light.

Figure 2. Schematic of plasma-enhanced chemical vapor deposition (PECVD) and physical vapor deposition (PVD) system experimental setup.

Figure 3. Scanning electron microscopy (SEM) image of a) pristine TiO₂ and TiO₂-Ag with b) 0.56 c) 2.97 wt% Ag content prepared by PECVD-PVD method and d) P25 film prepared by spin coating (a–c insets show the size distributions).

Figure 4. X-ray diffraction (XRD) pattern of nanoparticulate thin films prepared by PECVD-PVD an P25 film prepared by spin coating.

Figure 5. X-ray photoelectron spectroscopy (XPS) spectra of Ag 3d before and after annealing in N₂.

Figure 6. Absorbance spectra of the PECVD-PVD prepared nanoparticulate film and the P25 film prepared by spin coating.

Figure 7. Absorbance versus wavelength as a function of time corresponding to the photocatalytic degradation of R6G by a) TiO₂ and b) TiO₂-Ag 0.24 wt%; comparison of c) percent degradation and d) reaction rate constant of the degradation processes.

Table 1. Comparison of the photocatalytic activities reported in the present study and the literature.

Fabrication Process	Ag size	Photocatalytic Test Conditions and Results	Ref.
Liquid phase Solvothermal (AgNO3)	4 nm	500 mL, 50 mg/L dye, 1 g/L powder, methyl orange (MO), TiO2/Ag = 86% (180 min) TiO2 = < 5% (180 min)	(Karimi-Maleh et al. 2020)
Liquid phase Vapor evaporation (AgNO3)	4–9 nm	500 mL, 5 × 10^−5 M, 500 mg powder, MO, 80 min TiO2/Ag = 100% TiO2 = 5%	(Saravanan et al. 2018)
Liquid phase Hydrothermal (AgNO3)	20 nm	100 mL, 5 × 10^−6 M, 60 mg powder, Rhodamine 6 G (R6G) TiO2/Ag = 0.033 min^−1 (50 min) TiO2 = 0.010 min^−1 (150 min)	(Ng et al. 2012)
Liquid phase Sol–gel spin coating (AgNO3)	—	30 mL, 3 mg/L, 15 × 15 mm^2 film, Methylene blue, 480 min TiO2/Ag = 54.13% TiO2 = 36.32%	(Dermenci et al. 2014)
Liquid phase Hydrothermal (AgNO3)	∼10 nm	150 mL, 1 ppm, 20 mg powder P25/Ag = 0.0014 min (MO), 0.0008 min^−1 (R6G) P25 = 0.0002 min^−1 (R6G)	(Wu et al. 2019)
Gas phase PVD (Ag metal granules)	4–10 nm	3 mL, 5 mg/L dye, 0.06 mg 10 × 10 mm^2 film, R6G, 180 min TiO2/Ag = 36% (0.119 h^−1cm^−2) TiO2 = 19%	(Jiang et al. 2020) and this study

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