Efficient photocatalytic oxygen production over Ca-modified LaTiO2N

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	Efficient photocatalytic oxygen production over Ca-modified LaTiO2N
	Wu, Fangfang; Liu, Gang; Xu, Xiaoxiang; Xu, XX (reprint author), Tongji Univ, Sch Chem Sci & Engn, Shanghai Key Lab Chem Assessment & Sustainabil, 1239 Siping Rd, Shanghai 200092, Peoples R China.
	2017-02-01
发表期刊	JOURNAL OF CATALYSIS
ISSN	0021-9517
卷号	346 页码:10-20
摘要	LaTiO2N has been considered a promising candidate for efficient photocatalytic water splitting. However, its photocatalytic activity is often hampered by the presence of structural defects and poor charge mobility. In this work, we introduced Ca into the crystal structure of LaTiO2N via a simple co-precipitation method and investigated the photocatalytic and photoelectrochemical properties for the full range solid solution La1-xCaxTiO2+yN1-y (0 <= x, y <= 1). Our results show that incorporating Ca into LaTiO2N induces a strong structural shrinkage as well as a space group change from I mma to P nma around a middle doping point (x = 0.5). The presence of Ca effectively boosts the photocatalytic oxygen production and aids photocurrent extraction for LaTiO2N. The best photocatalytic activity was achieved for sample La0.3Ca0.7TiO2.7N0.3 with oxygen production rate similar to 66.96 mu mol/h under visible light illumination (lambda >= 420 nm), corresponding to apparent quantum efficiency similar to 3.13%. XPS analysis revealed a substantial reduction in surface Ti3+ species and a removal of A-site cation segregation for samples containing Ca. Further photoelectrochemical analysis highlights the critical role of Ca in enhancing the charge mobility of LaTiO2N. The better photocatalytic performance of Ca-modified LaTiO2N can be understood as a result of defect removal, high charge mobility, and improved surface charge migration pathways that considerably prolong the lifetimes of photogenerated charges. (C) 2016 Elsevier Inc. All rights reserved.; LaTiO2N has been considered a promising candidate for efficient photocatalytic water splitting. However, its photocatalytic activity is often hampered by the presence of structural defects and poor charge mobility. In this work, we introduced Ca into the crystal structure of LaTiO2N via a simple co-precipitation method and investigated the photocatalytic and photoelectrochemical properties for the full range solid solution La1-xCaxTiO2+yN1-y (0 <= x, y <= 1). Our results show that incorporating Ca into LaTiO2N induces a strong structural shrinkage as well as a space group change from I mma to P nma around a middle doping point (x = 0.5). The presence of Ca effectively boosts the photocatalytic oxygen production and aids photocurrent extraction for LaTiO2N. The best photocatalytic activity was achieved for sample La0.3Ca0.7TiO2.7N0.3 with oxygen production rate similar to 66.96 mu mol/h under visible light illumination (lambda >= 420 nm), corresponding to apparent quantum efficiency similar to 3.13%. XPS analysis revealed a substantial reduction in surface Ti3+ species and a removal of A-site cation segregation for samples containing Ca. Further photoelectrochemical analysis highlights the critical role of Ca in enhancing the charge mobility of LaTiO2N. The better photocatalytic performance of Ca-modified LaTiO2N can be understood as a result of defect removal, high charge mobility, and improved surface charge migration pathways that considerably prolong the lifetimes of photogenerated charges. (C) 2016 Elsevier Inc. All rights reserved.
部门归属	[wu, fangfang ; xu, xiaoxiang] tongji univ, sch chem sci & engn, shanghai key lab chem assessment & sustainabil, 1239 siping rd, shanghai 200092, peoples r china ; [liu, gang] chinese acad sci, inst met res, shenyang natl lab mat sci, 72 wenhua rd, shenyang 110016, peoples r china
关键词	Photocatalyst Water Splitting Latio2n Oxygen Production
学科领域	Chemistry, Physical ; Engineering, Chemical
资助者	Young Scientists Fund of the National Natural Science Foundation of China [21401142]; Recruitment Program of Global Youth Experts (1000 plan); Shanghai Science and Technology Commission [14DZ2261100]; Fundamental Research Funds for the Central Universities
收录类别	SCI
语种	英语
WOS记录号	WOS:000394195100002
引用统计	被引频次：52[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/78307
专题	中国科学院金属研究所
通讯作者	Xu, XX (reprint author), Tongji Univ, Sch Chem Sci & Engn, Shanghai Key Lab Chem Assessment & Sustainabil, 1239 Siping Rd, Shanghai 200092, Peoples R China.
推荐引用方式 GB/T 7714	Wu, Fangfang,Liu, Gang,Xu, Xiaoxiang,et al. Efficient photocatalytic oxygen production over Ca-modified LaTiO2N[J]. JOURNAL OF CATALYSIS,2017,346:10-20.
APA	Wu, Fangfang,Liu, Gang,Xu, Xiaoxiang,&Xu, XX .(2017).Efficient photocatalytic oxygen production over Ca-modified LaTiO2N.JOURNAL OF CATALYSIS,346,10-20.
MLA	Wu, Fangfang,et al."Efficient photocatalytic oxygen production over Ca-modified LaTiO2N".JOURNAL OF CATALYSIS 346(2017):10-20.