Preparation of ultrafine WC-Co powder via fluidized bed

In this study,the effects of reaction parameters on the deep-reduction and carbonization process of WO_(2)-Co to WC-Co were studied.The results indicate that the oxygen loss rate of WO_(2) is positively correlated with temperature and methane partial pressure.The partial pressure of methane has no significant effect on the formation rate of WC.The carbon content and particle size of the product increase with the increase of CH_(4) partial pressure.By synergistically regulating the reaction temperature to 950℃,the CH_(4) partial pressure to 1.25%,and the reaction time to 60 min,ultrafine WC-Co powder without h phase can be obtained.The particle size of the composite powder is 128 nm,with total carbon content of 6.16%,free carbon content of 0.4%,and residual oxygen content of 0.05%,respectively.The growth rate relationship of tungsten carbide is as follows:δ(t)=1.21×10^(-13)exp(-12809.72/T)√t.

Recent advances in elaborate interface regulation of BiVO_(4)photoanode for photoelectrochemical water splitting

Bismuth vanadate(BiVO_(4))is an excellent photoanode material for photoelectrochemical(PEC)water splitting system,possessing high theoretical photoelectrocatalytic conversion efficiency.However,the actual PEC activity and stability of BiVO_(4)are faced with great challenges due to factors such as severe charge recombination and slow water oxidation kinetics at the interface.Therefore,various interface regulation strategies have been adopted to optimize the BiVO_(4)photoanode.This review provides an in-depth analysis for the mechanism of interface regulation strategies from the perspective of factors affecting the PEC performance of BiVO_(4)photoanodes.These interface regulation strategies improve the PEC performance of BiVO_(4)photoanode by promoting charge separation and transfer,accelerating interfacial reaction kinetics,and enhancing stability.The research on the interface regulation strategies of BiVO_(4)photoanode is of great significance for promoting the development of PEC water splitting technology.At the same time,it also has inspiration for providing new ideas and methods for designing and preparing efficient and stable catalytic materials.

ZnS-embedded porous carbon for peroxydisulfate activation:Enhanced electron transfer for bisphenol A degradation

Transition metal sulfides have garnered increasing attention for their role in persulfate activation,a crucial process in environmental remediation.However,the function of metal sulfides without reversible valence changes,such as ZnS,remains largely unexplored in this context.Here we report ZnS-embedded porous carbon(ZnS-C),synthesized through the pyrolysis of Zn-MOF-74 and dibenzyl disulfide.ZnS-C demonstrates remarkable activity in activating peroxydisulfate(PDS)across a wide pH range,enabling the efficient mineralization removal of bisphenol A(BPA).Through electrochemical investigation and theoretical simulations of charge density distributions,we unveil that the electron transfer from BPA to PDS mediated by the ZnS-C catalyst governs the reaction.This study,both in theory and experiment,demonstrates metal sulfide as electron pump that enhances electron transfer efficiency in PDS activation.These findings redefine the role of metal sulfide catalysts,shedding new light on their potential for regulating reaction pathways in PDS activation processes.