Size- and composition-dependent photocatalytic hydrogen production over colloidal Cd1-xZnxSe nanocrystals
Size- and composition-dependent photocatalytic hydrogen production over colloidal Cd1-xZnxSe nanocrystals
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胶体 Cd1-xZnxSe 纳米晶体上尺寸和成分依赖性光催化制氢
DOI：
10.1016/j.ijhydene.2018.01.178
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发表时间：
2018-07-26
影响因子：
7.2
通讯作者：
Feng, Xiaoyang
中科院分区：
文献类型：
--
作者：
Chen, Yubin;Guo, Xu;Feng, Xiaoyang
胶体纳米晶由于具有可调的光学和光电性能，成为一种新型的太阳能制氢光催化剂。本文采用一步热注入法成功制备了尺寸和组成可调的Cd 1-xZnxSe纳米晶，并在可见光照射下进行光催化制氢。通过延长反应时间，首次制备出不同粒径的CdSe纳米粒子。结果表明，CdSe纳米粒子的导带位置与水还原电位之间的差异所产生的驱动力是决定其光催化性能的关键因素。粒径越小，驱动力越大，电子传递越快，光催化活性越高。在此基础上，制备了一系列不同成分的合金化Cd_（1-x）Zn_xSe纳米晶。随着Zn含量的增加，Cd_（1-x）Zn_xSe纳米粒子的光催化活性先增加后降低。Zn含量适中的Cd_（1-x）Zn_xSe具有最好的光催化产氢性能。推测Cd_（1-x）Zn_xSe纳米晶的光催化性能与驱动力和晶体结构有密切关系。本研究为通过简单控制粒径和组成来开发高效的光催化剂提供了指导。(C)2018年氢能出版有限责任公司。由爱思唯尔有限公司出版。保留所有权利。
Colloidal nanocrystals (NCs) have emerged as a new kind of photocatalysts for solar hydrogen production due to the tunable optical and photoelectrical properties. Herein, size- and composition-tunable alloyed Cd1-xZnxSe NCs were successfully prepared via a one-step hot injection method for photocatalytic hydrogen production under visible light irradiation. By prolonging the reaction time, CdSe NCs with the varied particle sizes were firstly fabricated. It is found that the driving force derived from the difference between conduction band position of CdSe NCs and water reduction potential played a key role in determining the photocatalytic performance. The larger driving force from smaller particle size would give rise to a faster electron transfer and better photocatalytic activity. Furthermore, a series of alloyed Cd1-xZnxSe NCs with different compositions were prepared. With the increased zinc amount, the photocatalytic activity of Cd1-xZnxSe NCs was initially increased and then decreased. Cd1-xZnxSe with the moderate Zn content exhibited the best photocatalytic hydrogen production. It is inferred that the photocatalytic performance of Cd1-xZnxSe NCs has a close relationship with the driving force and crystal structure. The present study can provide a guidance to develop efficient nanocrystal photocatalysts by simply controlling the particle size and composition. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.