Papers by Author: Jun Bo Zhong

Abstract: In this paper, SnO₂ and Fe₂O₃ doped-SnO₂ photocatalysts with different molar ratio of Fe/Sn were synthesized by a parallel flow coprecipitation method. The photocatalysts prepared were characterized by Brunauer-Emmett-Teller (BET) method, X-ray diffraction (XRD) and UV/Vis diffuse reflectance, respectively. The photocatalytic activity of photocatalysts prepared toward decolorization of methyl orange (MO) solution was evaluated. Of all of the photocatalysts prepared among the experimented compositions, Fe₂O₃ doped-SnO₂ with 1.5%Fe possesses the best photocatalytic activity.

Abstract: In this paper, ZnO photocatalyst was prepared by sol-gel method with the assistance of ionic liquid (IL). The structure, morphology and the photoinduced charge separation rate of the photocatalyst prepared (IL-ZnO) were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and surface photovoltage spectroscopy (SPS), respectively. The results reveal that ionic liquid enhances the photoinduced charge separation rate. The activity of ZnO for photocatalytic decolorization of methyl orange (MO) solution was evaluated. The results show that the photocatalytic activity of IL-ZnO is higher than that of ZnO.

Abstract: In this paper, parallel flaw precipitation method has been employed to fabricate nanostructured Co₃O₄ with the assistance of different surfactants. It is found that the surface parameters, SEM image and photocatalytic performance of Co₃O₄ have a strong dependence on the type of surfactants. The prepared photocatalysts Co₃O₄ were characterized by BET, XRD and SEM. The results show that Co3O4 prepared with the assistance of sodium dodecylbenzenesulfonate exhibits the best photocatalytic activity among the experimented compositions. The surface parameters and SEM all play an important role in promotion of photocatalytic activity of Co₃O₄ prepared.

Abstract: This report has shown that the dye of Methyl Orange (MO) in water can be decolorized effectively in the presence of KIO₃ under UV irradiation. Decolorisation efficiency of MO increases as the loading of KIO₃ increases and has no an optimal amount of KIO₃ in this case. The kinetic result shows that the decolorisation reaction is a pseudo first-order reaction when the concentration of MO is below 10 mgL-1. The influences of the pH value and hydroxyl radical scavengers on the decolorisation reaction were investigated in detailed. Several observations indicate that the mechanism is not the attack of hydroxyl radicals in MO decolorisation with KIO₃ under UV irradiation. More considerations should be focused on the underlying possible decolorisation mechanism of MO with KIO₃ under UV irradiation.

Abstract: In this paprer, ZnO was loaded on SiO₂ by sol-gel method. The prepared photocatalysts were characterized by BET, XRD, UV-Vis diffuse reflectance spectroscopy and surface photovoltage spectroscopy (SPS). The paper reveals that the photocatalytic activity of ZnO towards the decomposition of methyl orange can be greatly improved by loading ZnO on the surface of SiO₂. 80% SiO₂ possesses the best photocatalytic activity among the experimented compositions.

Abstract: In this paper, parallel flaw precipitation method has been employed to fabricate nanostructured Bi₂O₃. It is found that the surface parameters, bandgap, the photoinduced charge separation rate and photocatalytic performance of Bi₂O₃ have a strong dependence on the pH value of precipitation reaction.The prepared photocatalysts were characterized by BET, XRD, UV-Vis diffuse reflectance and surface photovoltage spectroscopy (SPS). The results show that Bi₂O₃ prepared under pH value10.0 exhibits the best photocatalytic activity among the experimented compositions. The results of further experiments show that surface parameters, bandgap, the photoinduced charge separation rate all play an important role in promotion of photocatalytic activity of Bi₂O₃ prepared under pH value 10.0.

Abstract: In this paper, Bi₂O₃ and Fe³⁺-doped Bi₂O₃ photocatalysts with different molar ratio of Bi /Fe (nBi:nFe =100:1,2,3,4) was prepared by paralled flaw co-precipitation method. The prepared photocatalysts were characterized by Brunauer-Emmet Teller (BET) method, X-ray diffraction( XRD) and UV-Vis diffuse reflectance spectroscopy. The results show that 3% Fe³⁺-Bi₂O₃ prepared has the highest BET surface area, pore volume, the smallest pore size and the particle average size. 3% Fe³⁺-Bi₂O₃ exhibits the best photocatalytic activity. The results of further experiments show that the specific surface area, UV-Vis diffuse reflectance all play an important role in promotion of photocatalytic activity of Bi₂O₃ nanostructure.

Abstract: Paralled flaw precipitation method has been employed to synthesize nanostructured ZnO. The prepared photocatalyst was characterized by BET, XRD. The paper reveals that Methyl Orange (MO) can be decolorized effectively in ZnO suspension system under UV irradiation. The optimal loading of photocatalyst in our experimental condition for the decolorization of MO is 1g/L. The present study, on the base of Langmuir-Hinshelwood mechanism, illustrates that the decolorization reaction is a pseudo first order kinetic model with the limiting rate constant of 8.48×10-2 mgL-1min-1 and equilibrium adsorption constant 0.335 L/mg, respectively.

Abstract: It has been found that the photocatalytic activity of ZnO toward the decolorization of Methyl Orange solution can be greatly improved by loading Ag on the surface of ZnO using a photodeposition method. The photocatalysts were characterized by X-ray diffraction(XRD), UV-Vis diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy(XPS), respectively. 0.5%Ag/ZnO demonstrates 2.13 times the photocatalytic activity of pure ZnO.