Papers by Author: Jian Zhang Li

Abstract: One novel dodecyliminodiacetate nickel(II) complexes were synthesized and characterized, and these complexes were used as mimic hydrolytic in catalytic hydrolysis of carboxylic ester (PNPP, p-nitrophenyl picolinate). The analysis of specific absorption spectra of the hydrolytic reaction systems indicated that the catalytic hydrolysis involved the key intermediates formed by PNPP with nickel(II) complexes. The kinetic parameter of PNPP catalytic hydrolysis has been calculated and the activation energy for the catalytic hydrolysis is 1.174 kJ•mol-1.

Abstract: This paper reveals that photocatalytic activity of Bi₂O₃ under visible light towards the decolorization of Methyl Orange solution can be greatly enhanced by doping Pr into the lattice of Bi₂O₃ using a sol-gel method. The photocatalysts were characterized by BET, UV-Vis diffuse reflectance spectroscopy and surface photovoltage spectroscopy (SPS), respectively. The result shows that 4%Pr doped Bi₂O₃ possesses the best photocatalytic activity under visible light.

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: It has been found that the photocatalytic activity of Bi₂O₃ toward the decolorization of Methyl Orange solution can be greatly improved by loading Ag on the surface of Bi₂O₃ using a photodeposition method. The photocatalysts were characterized by X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy and surface photovoltage spectroscopy (SPS), respectively. 0.5%Ag/Bi₂O₃ possesses the best photocatalytic activity.

Abstract: Abstract. Bismuth oxide is an important metal-oxide semicondutor, the interest in developing methods which can prepare Bi₂O₃ with unique properties has been a hot issue recently. In this paper, paralled flaw precipitation method has been employed to synthesize nanostructured Bi₂O₃. It is found that the bandgap and photocatalytic performance of Bi₂O₃ has a strong dependence on the pH value of precipitation reaction.The prepared photocatalysts were characterized by BET, XRD and UV-Vis diffuse reflectance. The results show that Bi2O3 prepared under pH value 8.5 has the highest BET surface area, pore volume, the smallest pore size and the average crystal size. Bi₂O₃ prepared under pH value 8.5 exhibits the best photocatalytic activity. The results of further experiments show that bandgap and the specific surface area all play an important role in promotion of photocatalytic activity of Bi₂O₃ prepared under pH 8.5.

Abstract: The photocatalytic activity of Bi₂O₃ photocatalyst towards decolorization of Methyl Orange (MO) was studied by employing several reagents. The influence of H2O2 on the decolorization efficiency was investigated in detail. Addition of ions such as CO₃²⁻, Cl⁻, and SO₄^2- inhibits the photocatalytic efficiency.

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.