Zhu Dongxu, Ye Haihang, Liu Zheming, Liu Jun, Fu Hao, Huang Yanbin, Teng Feng, Wang Zhijie, Tang Aiwei
Key Laboratory of Luminescence and Optical Information, Ministry of Education, School of Science, Beijing Jiaotong University, Beijing 100044, China.
Nanoscale. 2020 Mar 14;12(10):6111-6120. doi: 10.1039/c9nr10004k. Epub 2020 Mar 4.
Multinary copper-based chalcogenide nanocrystals (NCs) as light-driven photocatalysts have attracted extensive research interest due to their great potential for generating sustainable energy without causing environmental concerns. However, systematic studies on the growth mechanism and related photocatalytic activities involving different valent metal ions (either M or N) as foreign cations and monoclinic CuS NCs as the 'parent lattice' have rarely been carried out. In this work, we report an effective seed-mediated method for the synthesis of heterostructured CuS-MS NCs (M = Zn, Cd and Mn) and alloyed CuNS NCs (N = In and Ga). A typical cation exchange process took place prior to the growth of heterostructured NCs, while further inter-cation diffusion occurred only for the alloyed NCs. When compared with CuS NCs, all the heterostructured CuS-MS NCs and CuGaS NCs showed enhanced photocatalytic activities toward hydrogen production by water splitting, owing to their tailored optical band gaps and energy level alignments. Although optically favored, CuInS ANCs were not comparable to others due to their low conduction band minimum for the reduction of HO to H.
多元铜基硫族化物纳米晶体（NCs）作为光驱动光催化剂，因其在产生可持续能源且不引起环境问题方面的巨大潜力而引起了广泛的研究兴趣。然而，关于以不同价态金属离子（M或N）作为外来阳离子以及单斜CuS NCs作为“母体晶格”的生长机制和相关光催化活性的系统研究却很少进行。在这项工作中，我们报道了一种有效的种子介导方法，用于合成异质结构的CuS-MS NCs（M = Zn、Cd和Mn）以及合金化的CuNS NCs（N = In和Ga）。在异质结构NCs生长之前发生了典型的阳离子交换过程，而仅合金化的NCs发生了进一步的阳离子间扩散。与CuS NCs相比，所有异质结构的CuS-MS NCs和CuGaS NCs对水分解制氢均表现出增强的光催化活性，这归因于它们定制的光学带隙和能级排列。尽管在光学上具有优势，但由于其将HO还原为H的导带最小值较低，CuInS ANCs与其他材料相比并无优势。
