Oriented Built-in Electric Field Introduced by Surface Gradient Diffusion Doping for Enhanced Photocatalytic H2 Evolution in CdS Nanorods
Oriented Built-in Electric Field Introduced by Surface Gradient Diffusion Doping for Enhanced Photocatalytic H2 Evolution in CdS Nanorods
复制标题
通过表面梯度扩散掺杂引入定向内置电场，增强 CdS 纳米棒光催化析氢
DOI：
10.1021/acs.nanolett.7b01147
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发表时间：
2017-06-01
期刊：
影响因子：
10.8
通讯作者：
Xu, Zhongzi
中科院分区：
文献类型：
--
作者：
Huang, Hengming;Dai, Baoying;Xu, Zhongzi
元素掺杂已被广泛尝试用于开发可见光驱动的光催化剂，其引入杂质水平并增强光吸收。然而，掺杂剂也可以成为光生电子和空穴的复合中心。为了解决复合的挑战，我们报告了一个梯度磷掺杂的CdS（CdS-P）同质结纳米结构，创造了一个定向的内置电场，有效地提取载体从内部到表面的光催化剂。在420 nm处，无助催化剂的光催化剂的表观量子效率（AQY）高达8.2%，而放氢速率则提高到194.3 μ mol·h（-1）·mg（-1），是未加助催化剂的CdS的58.3倍。这种由表面梯度扩散掺杂引入的定向内建电场的概念应该为设计用于高效的太阳能到化学转化的其他类型的半导体光催化剂提供新的方法。
Element doping has been extensively attempted to develop visible-light-driven photocatalysts, which introduces impurity levels and enhances light absorption. However, the dopants can also become recombination centers for photogenerated electrons and holes. To address the recombination challenge, we report a gradient phosphorus-doped CdS (CdS-P) homojunction nanostructure, creating an oriented built-in electric-field for efficient extraction of carriers from inside to surface of the photocatalyst. The apparent quantum efficiency (AQY) based on the cocatalyst-free photocatalyst is up to 8.2% at 420 nm while the H-2 evolution rate boosts to 194.3 mu mol.h(-1).mg(-1), which is 58.3 times higher than that of pristine CdS. This concept of oriented built-in electric field introduced by surface gradient diffusion doping should provide a new approach to design other types of semiconductor photocatalysts for efficient solar-to-chemical conversion.