Band alignment and enhanced photocatalytic activation of alpha/beta-Bi2O3 heterojunctions via in situ phase transformation

IMR OpenIR

	Band alignment and enhanced photocatalytic activation of alpha/beta-Bi2O3 heterojunctions via in situ phase transformation
	Shan, Lianwei; Wang, Guilin; Li, Dan; San, Xingyuan; Liu, Lizhu; Dong, Limin; Wu, Ze; shlw0531@163.com
	2015
发表期刊	DALTON TRANSACTIONS
ISSN	1477-9226
卷号	44 期号:17 页码:7835-7843
摘要	The assembling heterojunction, one of the key topics in photocatalysts and semiconductors (SCs), is generally accomplished in at least two steps, of which the first step is the synthesis of a matrix, and then the growth of the second phase on the matrix. Herein we present the preparation of alpha/beta-Bi2O3 heterojunctions by an in situ phase transformation technique. Under normal pressure, a facile citrate method was used to synthesize beta-Bi2O3 nanosheets and alpha/beta-Bi2O3 heterojunctions. The novel features of the process are the mild operating conditions by an appropriate selection of heat treatment temperature and time. Using transmission electron microscopy (TEM), we found that a number of nano-sized alpha-Bi2O3 form on the beta-Bi2O3 nanosheet via a controlled beta ->alpha phase transition, generating a large number of heterojunctions. The CM1 (calcining beta-Bi2O3 precursor at 363 degrees C for 4 h) heterojunction achieves a strong visible light absorption and dye absorption capacity and produces a very high reaction rate for Rhodamine B (RhB) photodegradation. Electrochemical impedance spectroscopy (EIS) revealed excellent charge transfer characteristics of the heterojunction, which accounts for its high photoactivity. Using the X-ray electron valence band spectra, it is found that the valence band of alpha-Bi2O3 is more negative than that of beta-Bi2O3. Thus, in heterojunctions, the photogenerated holes in beta-Bi2O3 are transferred to alpha-Bi2O3 with good charge transport characteristics by the intrinsic driving force in the interface field. Furthermore, a separated hole can accomplish a transfer process from alpha-Bi2O3 to the aqueous solution within its lifetime due to the diameter of a-Bi2O3 being less than 17.6 nm.
部门归属	[shan, lianwei ; wang, guilin ; li, dan ; liu, lizhu ; dong, limin ; wu, ze] harbin univ sci & technol, coll mat sci & engn, key lab mat res & applicat heilongjiang prov, harbin 150040, peoples r china ; [shan, lianwei] harbin univ sci & technol, coll chem & environm engn, coll heilongjiang prov, key lab green chem engn & technol, harbin 150040, peoples r china ; [san, xingyuan] chinese acad sci, inst met res, shenyang natl lab mat sci, shenyang 110016, peoples r china
资助者	Education Department Program of Heilongjiang Province [12541111]; Key Laboratory of Green Chemical Engineering and Technology of the College of Heilongjiang Province
收录类别	sci
语种	英语
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/74649
专题	中国科学院金属研究所
通讯作者	shlw0531@163.com
推荐引用方式 GB/T 7714	Shan, Lianwei,Wang, Guilin,Li, Dan,et al. Band alignment and enhanced photocatalytic activation of alpha/beta-Bi2O3 heterojunctions via in situ phase transformation[J]. DALTON TRANSACTIONS,2015,44(17):7835-7843.
APA	Shan, Lianwei.,Wang, Guilin.,Li, Dan.,San, Xingyuan.,Liu, Lizhu.,...&shlw0531@163.com.(2015).Band alignment and enhanced photocatalytic activation of alpha/beta-Bi2O3 heterojunctions via in situ phase transformation.DALTON TRANSACTIONS,44(17),7835-7843.
MLA	Shan, Lianwei,et al."Band alignment and enhanced photocatalytic activation of alpha/beta-Bi2O3 heterojunctions via in situ phase transformation".DALTON TRANSACTIONS 44.17(2015):7835-7843.