Lin Jianfei, Liu Yong, Liu Yongping, Huang Chen, Liu Wenhui, Mi Xihong, Fan Dayong, Fan Fengtao, Lu Huidan, Chen Xiaobo
Guangxi Key Laboratory of Electrochemical and Magneto-chemical, Functional Materials, College of Chemistry and Bioengineering, Guilin University of Technology, Guilin, 541004, P.R. China.
State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian, 116023, P.R. China.
ChemSusChem. 2019 Mar 7;12(5):961-967. doi: 10.1002/cssc.201802691. Epub 2019 Feb 4.
Improving the separation efficiency of photogenerated electron-hole pairs and the conductivity of electrons to photoanode substrates are critical to achieve high-performance photoelectrochemical (PEC) water splitting. Here, a SnS /H-TiO /Ti heterojunction photoanode was fabricated with SnS nanosheets vertically grown on hydrogen-treated TiO (H-TiO ) nanotube arrays on a Ti substrate. It showed a significantly enhanced photocurrent of 4.0 mA cm at 1.4 V (vs. reversible hydrogen electrode) under AM 1.5 G illumination, 70 times higher than that of SnS /TiO /Ti. Kelvin probe force microscopy measurements indicated that photogenerated electrons could be easily transported through the SnS /H-TiO interface but not through the SnS /TiO interface. Through hydrogen treatment, defects were created in H-TiO nanotubes to convert type I junctions to type II with SnS nanosheets. As a result, a high efficiency of electron-hole separation at the SnS /H-TiO interface and a high electron conductivity in H-TiO nanotubes were achieved and improved PEC performance. These findings show an effective route towards high-performance photoelectrodes for water splitting.
提高光生电子 - 空穴对的分离效率以及电子向光阳极基底的传导率对于实现高性能光电化学（PEC）水分解至关重要。在此，通过在钛基底上的氢处理二氧化钛（H - TiO ）纳米管阵列上垂直生长硫化锡纳米片，制备了一种SnS /H - TiO /Ti异质结光阳极。在AM 1.5 G光照下，它在1.4 V（相对于可逆氢电极）时显示出显著增强的光电流，为4.0 mA cm ，比SnS /TiO /Ti的光电流高70倍。开尔文探针力显微镜测量表明，光生电子可以轻松地通过SnS /H - TiO界面传输，但不能通过SnS /TiO界面传输。通过氢处理，在H - TiO纳米管中产生了缺陷，从而使与硫化锡纳米片的结从I型转变为II型。结果，在SnS /H - TiO界面实现了高效的电子 - 空穴分离，并且H - TiO纳米管中的电子传导率提高，从而改善了PEC性能。这些发现展示了一条通往用于水分解的高性能光电极的有效途径。
