Ag/Ag 2 S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmo... more Ag/Ag 2 S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmonic Ag + reduction through a photo-deposition method. Ag 2 S was introduced to narrow the overall composite bandgap and activate the surface plasmon resonance (SPR) effect of the Ag + cation present. The physicochemical properties of the as-synthesised catalysts were characterised by X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM), Brunauer-Emmett-Teller (BET) analysis. Fourier-transform infrared spectroscopy (FTIR), Ultraviolet diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence emission spectra (PL) and X-ray photoelectron spectroscopy (XPS) was conducted to investigate the photo-absorption and emission spectra of the nanocomposites. The degradation efficiency of all the synthesised catalysts (ZnO, Ag 2 S, Ag/ZnO and Ag 2 S/ZnO) prior to the final product, Ag/ Ag 2 S/ZnO was tested and compared. Results showed that the ternary Ag/Ag2S/ZnO achieved a 98 % phenol removal compared to 50 %, 11 %, 64 % and 93 % for ZnO, Ag2S, Ag/ZnO and binary Ag2S/ZnO, respectively. The degradation kinetics followed the Langmuir-Hinshelwood model, which typically describes heterogeneous photocatalytic surface reactions. The linear fits had R 2 values higher than 0.97, which confirms the degree of accuracy or statistical fitness to the kinetic model. Degradation scavenger test confirmed the holes (h +) as the main inhibitor and identified the superoxide O 2 radical as the main active specie responsible for the degradation. Total organic carbon analysis using the ternary Ag/Ag 2 S-ZnO catalyst only achieved a 74% phenol mineralization after 24 h of photocatalysis. Recyclability tests showed good phenol removal stability of Ag/Ag 2 S-ZnO at 41 % after five recycle runs. Hence, a synergistic degradation mechanism responsible for the efficient photo-degradation performance was proposed.
Ag/Ag 2 S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmo... more Ag/Ag 2 S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmonic Ag + reduction through a photo-deposition method. Ag 2 S was introduced to narrow the overall composite bandgap and activate the surface plasmon resonance (SPR) effect of the Ag + cation present. The physicochemical properties of the as-synthesised catalysts were characterised by X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM), Brunauer-Emmett-Teller (BET) analysis. Fourier-transform infrared spectroscopy (FTIR), Ultraviolet diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence emission spectra (PL) and X-ray photoelectron spectroscopy (XPS) was conducted to investigate the photo-absorption and emission spectra of the nanocomposites. The degradation efficiency of all the synthesised catalysts (ZnO, Ag 2 S, Ag/ZnO and Ag 2 S/ZnO) prior to the final product, Ag/ Ag 2 S/ZnO was tested and compared. Results showed that the ternary Ag/Ag2S/ZnO achieved a 98 % phenol removal compared to 50 %, 11 %, 64 % and 93 % for ZnO, Ag2S, Ag/ZnO and binary Ag2S/ZnO, respectively. The degradation kinetics followed the Langmuir-Hinshelwood model, which typically describes heterogeneous photocatalytic surface reactions. The linear fits had R 2 values higher than 0.97, which confirms the degree of accuracy or statistical fitness to the kinetic model. Degradation scavenger test confirmed the holes (h +) as the main inhibitor and identified the superoxide O 2 radical as the main active specie responsible for the degradation. Total organic carbon analysis using the ternary Ag/Ag 2 S-ZnO catalyst only achieved a 74% phenol mineralization after 24 h of photocatalysis. Recyclability tests showed good phenol removal stability of Ag/Ag 2 S-ZnO at 41 % after five recycle runs. Hence, a synergistic degradation mechanism responsible for the efficient photo-degradation performance was proposed.
Ag/Ag 2 S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmo... more Ag/Ag 2 S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmonic Ag + reduction through a photo-deposition method. Ag 2 S was introduced to narrow the overall composite bandgap and activate the surface plasmon resonance (SPR) effect of the Ag + cation present. The physicochemical properties of the as-synthesised catalysts were characterised by X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM), Brunauer-Emmett-Teller (BET) analysis. Fourier-transform infrared spectroscopy (FTIR), Ultraviolet diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence emission spectra (PL) and X-ray photoelectron spectroscopy (XPS) was conducted to investigate the photo-absorption and emission spectra of the nanocomposites. The degradation efficiency of all the synthesised catalysts (ZnO, Ag 2 S, Ag/ZnO and Ag 2 S/ZnO) prior to the final product, Ag/ Ag 2 S/ZnO was tested and compared. Results showed that the ternary Ag/Ag2S/ZnO achieved a 98 % phenol removal compared to 50 %, 11 %, 64 % and 93 % for ZnO, Ag2S, Ag/ZnO and binary Ag2S/ZnO, respectively. The degradation kinetics followed the Langmuir-Hinshelwood model, which typically describes heterogeneous photocatalytic surface reactions. The linear fits had R 2 values higher than 0.97, which confirms the degree of accuracy or statistical fitness to the kinetic model. Degradation scavenger test confirmed the holes (h +) as the main inhibitor and identified the superoxide O 2 radical as the main active specie responsible for the degradation. Total organic carbon analysis using the ternary Ag/Ag 2 S-ZnO catalyst only achieved a 74% phenol mineralization after 24 h of photocatalysis. Recyclability tests showed good phenol removal stability of Ag/Ag 2 S-ZnO at 41 % after five recycle runs. Hence, a synergistic degradation mechanism responsible for the efficient photo-degradation performance was proposed.
Ag/Ag 2 S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmo... more Ag/Ag 2 S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmonic Ag + reduction through a photo-deposition method. Ag 2 S was introduced to narrow the overall composite bandgap and activate the surface plasmon resonance (SPR) effect of the Ag + cation present. The physicochemical properties of the as-synthesised catalysts were characterised by X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM), Brunauer-Emmett-Teller (BET) analysis. Fourier-transform infrared spectroscopy (FTIR), Ultraviolet diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence emission spectra (PL) and X-ray photoelectron spectroscopy (XPS) was conducted to investigate the photo-absorption and emission spectra of the nanocomposites. The degradation efficiency of all the synthesised catalysts (ZnO, Ag 2 S, Ag/ZnO and Ag 2 S/ZnO) prior to the final product, Ag/ Ag 2 S/ZnO was tested and compared. Results showed that the ternary Ag/Ag2S/ZnO achieved a 98 % phenol removal compared to 50 %, 11 %, 64 % and 93 % for ZnO, Ag2S, Ag/ZnO and binary Ag2S/ZnO, respectively. The degradation kinetics followed the Langmuir-Hinshelwood model, which typically describes heterogeneous photocatalytic surface reactions. The linear fits had R 2 values higher than 0.97, which confirms the degree of accuracy or statistical fitness to the kinetic model. Degradation scavenger test confirmed the holes (h +) as the main inhibitor and identified the superoxide O 2 radical as the main active specie responsible for the degradation. Total organic carbon analysis using the ternary Ag/Ag 2 S-ZnO catalyst only achieved a 74% phenol mineralization after 24 h of photocatalysis. Recyclability tests showed good phenol removal stability of Ag/Ag 2 S-ZnO at 41 % after five recycle runs. Hence, a synergistic degradation mechanism responsible for the efficient photo-degradation performance was proposed.
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