Reducing the surface defects of Ta3N5 photoanode towards enhanced photoelectrochemical water oxidation

被引：27

作者：

Shao, Chenyi ^{[1
,2
]}

Chen, Ruotian ^{[1
]}

Zhao, Yongle ^{[1
,2
]}

Li, Zheng ^{[1
]}

Zong, Xu ^{[1
]}

Li, Can ^{[1
]}

机构：

[1] Chinese Acad Sci, Dalian Natl Lab Clean Energy, Collaborat Innovat Ctr Chem Energy Mat iChEM, State Key Lab Catalysis,Dalian Inst Chem Phys, Zhongshan Rd 457, Dalian 116023, Peoples R China

[2] Univ Chinese Acad Sci, Beijing 100049, Peoples R China

来源：

JOURNAL OF MATERIALS CHEMISTRY A | 2020年 / 8卷 / 44期

基金：

国家重点研发计划; 中国国家自然科学基金;

关键词：

TANTALUM NITRIDE PHOTOANODE; PHOTOCATALYTIC PERFORMANCE; NANOTUBE PHOTOANODES; FABRICATION; TAON; TRANSPORT; CATALYST; LAYER; FILMS;

D O I：

10.1039/d0ta08121c

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Tuning the concentration and location of defects in semiconductors has been found to be effective in modifying their photoelectrochemical (PEC) performance. Herein, we present the fabrication of Ta3N5 photoanodes with reduced surface defects through the nitridation of a two-step-flame-heating-derived Ta2O5 precursor (TSFH-Ta2O5). We found that by using TSFH-Ta2O5 instead of the one-step-flame-heating-derived Ta2O5 (OSFH-Ta2O5), the concentrations of low valence Ta species on the surface of Ta2O5 and the resulting Ta3N5 photoelectrodes are reduced. Moreover, we clarified that low valence Ta species on the Ta3N5 surface led to the formation of undesirable surface states, which induces severe Fermi level pinning and aggravates charge recombination. Therefore, TSFH-Ta3N5 delivered enhanced charge separation and injection efficiencies for PEC water oxidation reaction. A photocurrent density of 6.8 mA cm(-2) at 1.23 V vs. reversible hydrogen electrode (RHE) was obtained on TSFH-Ta3N5 after loading a Co(OH)(x) cocatalyst, which is among the highest values reported for planar Ta3N5 photoanodes.

引用

页码：23274 / 23283

页数：10

共 47 条

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