In this work, an efficient AgVO3/MoS 2 composite photocatalyst was successfully synthesized via a hydrothermal method. The photocatalytic activity of the as-prepared photocatalyst was evaluated by using it for assessi...In this work, an efficient AgVO3/MoS 2 composite photocatalyst was successfully synthesized via a hydrothermal method. The photocatalytic activity of the as-prepared photocatalyst was evaluated by using it for assessing the degradation of different organic pollutants under visible-light irradiation. The composite 3%-AgVO3/MoS 2 catalyst demonstrated a significantly enhanced photocatalytic activity compared to the pure compounds（AgVO3 and MoS2）. The reason behind the excellent photocatalytic performance was the modification of MoS 2 by AgVO3 to facilitate O2 adsorption/activation. In addition, the composite catalyst facilitates the two-electron oxygen reduction reaction whereby H2O2 is generated on the surface of MoS 2 to produce additional reactive oxygen species（ROSs）. ESR coupled with the POPHA fluorescence detection method and a free radical capture experiment were used to elucidate the mechanism of formation of the ROSs, including ·OH, ·O2- and H2O2. Furthermore, the generation of additional ROSs could accelerate electron consumption, leaving behind more holes for the oxidation of organic pollutants. A possible photocatalytic mechanism of the composite is also discussed.展开更多
Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, XRD, SEM and EDAX data. U...Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, XRD, SEM and EDAX data. UV-Visible spectroscopy measurements reveal that the Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite has maximum absorption at 353.04 nm and this peak position reflects the band gap of particles and it is found to be 2.51 eV which was calculated using Tauc plot. X-Ray diffraction (XRD) reveals crystaline size to be 49.85 nm which was calculated using Williamson-Hall (W-H) plot method. Photocatalytic degradation of acetic acid, chloroacetic acid and trichloroacetic acid has been studied by volumetric method using NaOH solution. Photocatalytic degradation of chloroacetic acid and acetic acid follows first order kinetics. The photodegradation efficiency for Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite was found to be ≈97.8%. A Taft linear free energy relationship is noted for the catalysed reaction with ρ* = 0.233 and indicating electron withdrawing groups enhance the rate. An isokinetic relation is observed with β = 358 K indicating that enthalpy factor controls the reaction rate. The result of this paper suggests the possibility of degradation of organic compounds, industrial effluants and toxic organic compounds by photodegradation process by ecofriendly Al<sub>2</sub>S<sub>3</sub>/ MoS<sub>2</sub>. The antibacterial activity of Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite was investigated. These particles were shown to have an effective bactericide.展开更多
基金supported by the National Natural Science Foundation of China(21706104)the Natural Science Foundation of Jiangsu Province(BK20150484)+1 种基金the China Postdoctoral Science Foundation(2015M570416)the financial support of the Research Foundation of Jiangsu University,China(14JDG148)~~
文摘In this work, an efficient AgVO3/MoS 2 composite photocatalyst was successfully synthesized via a hydrothermal method. The photocatalytic activity of the as-prepared photocatalyst was evaluated by using it for assessing the degradation of different organic pollutants under visible-light irradiation. The composite 3%-AgVO3/MoS 2 catalyst demonstrated a significantly enhanced photocatalytic activity compared to the pure compounds（AgVO3 and MoS2）. The reason behind the excellent photocatalytic performance was the modification of MoS 2 by AgVO3 to facilitate O2 adsorption/activation. In addition, the composite catalyst facilitates the two-electron oxygen reduction reaction whereby H2O2 is generated on the surface of MoS 2 to produce additional reactive oxygen species（ROSs）. ESR coupled with the POPHA fluorescence detection method and a free radical capture experiment were used to elucidate the mechanism of formation of the ROSs, including ·OH, ·O2- and H2O2. Furthermore, the generation of additional ROSs could accelerate electron consumption, leaving behind more holes for the oxidation of organic pollutants. A possible photocatalytic mechanism of the composite is also discussed.
文摘Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite has been synthesized through electrochemical method and characterized by UV-Visible spectroscopy, XRD, SEM and EDAX data. UV-Visible spectroscopy measurements reveal that the Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite has maximum absorption at 353.04 nm and this peak position reflects the band gap of particles and it is found to be 2.51 eV which was calculated using Tauc plot. X-Ray diffraction (XRD) reveals crystaline size to be 49.85 nm which was calculated using Williamson-Hall (W-H) plot method. Photocatalytic degradation of acetic acid, chloroacetic acid and trichloroacetic acid has been studied by volumetric method using NaOH solution. Photocatalytic degradation of chloroacetic acid and acetic acid follows first order kinetics. The photodegradation efficiency for Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite was found to be ≈97.8%. A Taft linear free energy relationship is noted for the catalysed reaction with ρ* = 0.233 and indicating electron withdrawing groups enhance the rate. An isokinetic relation is observed with β = 358 K indicating that enthalpy factor controls the reaction rate. The result of this paper suggests the possibility of degradation of organic compounds, industrial effluants and toxic organic compounds by photodegradation process by ecofriendly Al<sub>2</sub>S<sub>3</sub>/ MoS<sub>2</sub>. The antibacterial activity of Al<sub>2</sub>S<sub>3</sub>/MoS<sub>2</sub> nanocomposite was investigated. These particles were shown to have an effective bactericide.
