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Advanced Powder Technology
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.
Advanced Powder Technology, 2022
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/Ag2S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmoni... more Ag/Ag2S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmonic Ag+ reduction through a photo-deposition method. Ag2S 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) to determine the crystallinity, while scanning and transmission electron microscopies (SEM and TEM) revealed the particle size and morphology. The surface area and pore sizes were measured using a Brunauer-Emmett-Teller (BET) analysis. Fouriertransform infrared spectroscopy (FTIR), Ultraviolet diffuse reflectance spectroscopy (UV-vis DRS) and photoluminescence emission spectra (PL) was conducted to investigate the photo-absorption and emission spectra of the nanocomposites. X-ray photoelectron spectroscopy (XPS), confirmed the surface electrochemical states and electron transfer between Ag/Ag2S and ZnO. Ternary Ag/Ag2S-ZnO catalyst demonstrated an excellent photo-generated charge separation efficiency by achieving 98% phenol degradation higher than ZnO, Ag/ZnO and Ag2S-ZnO composites due to its enhanced photosensitivity and SPR effect combined. The degradation for all the synthesized catalysts followed the Langmuir-Hinshelwood model, which typically describes heterogeneous photocatalytic surface reactions. All the fits had R2 values higher than 0.97, which confirms the degree of accuracy or statistical fitness to the kinetic model. Total organic carbon analysis using the ternary Ag/Ag2S-ZnO catalyst only achieved a 74% phenol mineralization after 24 hours of photocatalysis. Recyclability tests showed good degradation stability of Ag/Ag2S-ZnO after five recycle runs. Hence, a synergistic degradation mechanism responsible for the efficient photodegradation performance was proposed.
Advanced Powder Technology
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.
Advanced Powder Technology, 2022
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/Ag2S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmoni... more Ag/Ag2S-ZnO nanocomposites were prepared via a simple hydrothermal process followed by a plasmonic Ag+ reduction through a photo-deposition method. Ag2S 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) to determine the crystallinity, while scanning and transmission electron microscopies (SEM and TEM) revealed the particle size and morphology. The surface area and pore sizes were measured using a Brunauer-Emmett-Teller (BET) analysis. Fouriertransform infrared spectroscopy (FTIR), Ultraviolet diffuse reflectance spectroscopy (UV-vis DRS) and photoluminescence emission spectra (PL) was conducted to investigate the photo-absorption and emission spectra of the nanocomposites. X-ray photoelectron spectroscopy (XPS), confirmed the surface electrochemical states and electron transfer between Ag/Ag2S and ZnO. Ternary Ag/Ag2S-ZnO catalyst demonstrated an excellent photo-generated charge separation efficiency by achieving 98% phenol degradation higher than ZnO, Ag/ZnO and Ag2S-ZnO composites due to its enhanced photosensitivity and SPR effect combined. The degradation for all the synthesized catalysts followed the Langmuir-Hinshelwood model, which typically describes heterogeneous photocatalytic surface reactions. All the fits had R2 values higher than 0.97, which confirms the degree of accuracy or statistical fitness to the kinetic model. Total organic carbon analysis using the ternary Ag/Ag2S-ZnO catalyst only achieved a 74% phenol mineralization after 24 hours of photocatalysis. Recyclability tests showed good degradation stability of Ag/Ag2S-ZnO after five recycle runs. Hence, a synergistic degradation mechanism responsible for the efficient photodegradation performance was proposed.