Synthesis, characterization and enhanced photocatalytic performance of Ag2S-coupled ZnO/ZnS core/shell nanorods
Synthesis, characterization and enhanced photocatalytic performance of Ag2S-coupled ZnO/ZnS core/shell nanorods
复制标题
Ag2S耦合ZnO/ZnS核/壳纳米棒的合成、表征及增强光催化性能
DOI：
10.1016/j.jallcom.2013.03.149
复制
发表时间：
2013-08-15
影响因子：
6.2
通讯作者：
He, Zhong
中科院分区：
文献类型：
--
作者：
Liu, Shan;Wang, Xitao;He, Zhong
采用低温水热法和阳离子交换法相结合的方法，制备了一系列以ZnO纳米棒为核、ZnS-Ag 2S为壳层、不同Ag 2S/ZnS摩尔比的复合光催化剂。通过在ZnO纳米棒表面包覆一层ZnS和Ag 2S复合壳层，制备出直径约为150 nm，长度从几百nm到几微米的核/壳纳米棒，壳层主要由直径约为5-8 nm的纳米晶组成。SEM、TEM、EDX、XPS和UV-Vis DRS表征表明，壳层中Ag 2S/ZnS的摩尔比对ZnO/ZnS-Ag 2S核/壳纳米棒的形貌、组分分布、光吸收和光催化性能有很大影响。由于与低能带隙材料Ag 2S的耦合，ZnO/ZnS-Ag 2S纳米棒具有比ZnO/ZnS高得多的太阳模拟光吸收能力。结果表明，所制备的ZnO/ZnS-Ag 2S纳米复合材料对甘油水溶液制氢具有更高的催化效率。ZnO/ZnS-Ag 2 S核/壳纳米棒的上级光吸收性能和光催化性能可能是由于异质结构增强了光生电子-空穴对的分离。(C)2013爱思唯尔有限公司版权所有。
A series of composite photocatalysts comprised of ZnO nanorods core and ZnS-Ag2S heterostructural shell layer with different Ag2S/ZnS molar ratios have been synthesized via the combination of a low-temperature hydrothermal growth and cation exchange technique. The core/shell nanorods, with the diameters of about 150 nm and the lengths of ranging from a few 100 nm to several micrometers, were fabricated by coating the ZnO nanorods with a layer of ZnS and Ag2S composite shell mainly consisting of nanocrystals with the diameters of about 5-8 nm. The characterization from SEM, TEM, EDX, XPS, and UV-Vis DRS reveals that the molar ratio of Ag2S/ZnS in shell layer strongly affects the morphologies, distribution of components, photo absorption, and photocatalytic performance of the ZnO/ZnS-Ag2S core/shell nanorods. Due to the coupling with low bandgap material Ag2S, the ZnO/ZnS-Ag2S nanorods have a much higher solar-simulated light absorption capability than that of ZnO/ZnS. As a result, the as-prepared ZnO/ZnS-Ag2S nanocomposites exhibited much higher catalytic efficiency for the hydrogen production from glycerol aqueous solution. The superior photo absorption properties and photocatalytic performance of the ZnO/ZnS-Ag2S core/shell nanorods may be ascribed to the heterostructure, which enhanced the separation of photo-induced electron-hole pairs. (C) 2013 Elsevier B.V. All rights reserved.