二元ZnCo-LDH助催化剂对BiVO4光电化学性能的促进  

Promotion of Photoelectrochemical Performance of BiVO4 by Binary Zn Co-LDH Co-catalyst

作　　者：李娜[1] 王慕恒 赵勇 姚瑞 刘光[1] 李晋平[1] LI Na;WANG Mu-Heng;ZHAO Yong;YAO Rui;LIU Guang;LI Jin-Ping(Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization,Tianyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学气体能源高效清洁利用山西省重点实验室

出　　处：《无机化学学报》2019年第10期1773-1780,共8页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.21878204)资助项目

摘　　要：钒酸铋(BiVO4)是最有前景的将太阳能转化为氢能(STH)的光阳极材料之一,但其本身严重的电子-空穴复合严重影响了其实用性。本文中,我们报道了用一步电沉积法将高效的二元ZnCo-LDH助催化剂沉积在钒酸铋(BiVO4)光阳极上,大大提升了钒酸铋(BiVO4)的光吸收能力,并且加速了水氧化反应动力学,显著促进了光生空穴向半导体表面的转移,减轻了表面电荷复合。BiVO4/ZnCo-LDH光阳极在1.23V(vsRHE)偏压下,0.5mol·L^-1磷酸钾(KPi)电解液中的光电流密度达到2.85mA·cm-2,是纯BiVO4的2.59倍,且起始电位(Von)从930mV下降到270mV。BiVO4/ZnCo-LDH复合光阳极表现出65%的高表面电荷分离效率(1.23V(vsRHE)),而纯BiVO4的仅为30%。Bismuth vanadate(BiVO4)is one of the most promising photoanode materials for converting solar energy into hydrogen energy(STH).However,the practical application of BiVO4 is severely hindered by the intrinsically severe electron-hole recombination.Here,we reported bismuth vanadate(BiVO4)photoanode decorated with binary zinc-cobalt LDHs(ZnCo-LDH)co-catalyst by one-step electrodeposition method,which greatly enhances light absorption capacities of bismuth vanadate(BiVO4),accelerates water oxidation kinetics,facilitates efficient hole transfer to the surface and reduces the surface charge recombination.The hybrid photoanode exhibited a high photocurrent density of 2.85 mA·cm^-2 at 1.23 V(vs RHE),which corresponds to a 259%increase compared to that of the pristine BiVO4 photoanode.Furthermore,the onset potential(Von)has greatly decreased from 930 to 270 mV,which displays that OER kinetics is improved upon the deposition of ZnCo-LDH.In addition,the BiVO4/ZnCo-LDH composite photoanode showed a high surface charge separation efficiency of 65%,which is 2.17 times that of BiVO4.

关 键 词：钒酸铋 光电化学性能 ZnCo-LDH助催化剂 电荷分离 

分 类 号：O643.36[理学—物理化学] O614.21[理学—化学]