Fabrication and research of bi-functional CuNi_(2)S_(4) nanosheets decorated TiO_(2)/CuNi_(2)S_(4) heterojunction photoanode for photoelectrochemical water splitting  

作　　者：金伟 张立媛 张文静 孙倩 张德恺 苗慧 胡晓云 Wei Jin;Liyuan Zhang;Wenjing Zhang;Qian Sun;Dekai Zhang;Hui Miao;Xiaoyun Hu(School of Physics,Northwest University,Xi’an 710127,China)

机构地区：[1]School of Physics,Northwest University,Xi’an 710127,China

出　　处：《Chinese Physics B》2023年第11期124-133,共10页中国物理B(英文版)

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 11974276 and 11804274);the Natural Science Foundation of Shaanxi Province of China (Grant No. 2023-JC-YB-139);the Open Research Fund of State Key Laboratory of Transient Optics and Photonics;the Chinese Academy of Sciences (Grant No. SKLST202211)。

摘　　要：As a traditional n-type semiconductor, TiO_(2)has good UV absorption ability and stable physical and chemical properties. However, its wide band gap and low oxygen evolution reaction(OER) activity limit its application in the field of photoelectrochemical(PEC) water splitting. In this work, a type-Ⅱ TiO2/CuNi2S4heterojunction photoanode is successfully constructed, which expanded the light absorption range to visible and enhanced the OER activity. Firstly, TiO2nanotubes(NTs) thin films are prepared on Ti substrates by two-step anodization, and then the bi-functional electrocatalytic material CuNi2S4is grown on TiO2NTs in the shape of nanosheets(NSs) in situ by solvothermal method. As a bi-functional electrocatalytic material, CuNi2S4has good visible light absorption property as well as OER catalytic activity. Compared with TiO_(2), the IPCE value of TiO_(2)/CuNi_(2)S_(4)is 2.59% at 635 nm, and that of TiO2is a mere 0.002%.The separation efficiency and injection efficiency increase from 2.49% and 31.52% to 3.61% and 87.77%, respectively. At 1.23 V vs. RHE, the maximum photocurrent density is 0.26 m A/cm^(2), which is 2.6 times than that of TiO2(0.11 m A/cm^(2)),and can be maintained at 0.25 m A/cm^(2)for at least 2 h under light illumination. Moreover, a hydrogen production rate of 4.21 μmol·cm^(-2)·h^(-1)is achieved within 2 h. This work provides a new idea for the application of TiO_(2)in the field of PEC water splitting and the construction of efficient and stable photoelectronic devices.

关 键 词：TiO_(2) CuNi2S4 high stability photoelectrochemical properties 

分 类 号：TN304[电子电信—物理电子学]