Synthesis of Phase Junction Cadmium Sulfide Photocatalyst under Sulfur‐Rich Solution System for Efficient Photocatalytic Hydrogen Evolution

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2023-05, Vol.19 (19), p.e2207623-n/a
• Main Authors: Zheng, Xinlong, Song, Yiming, Liu, Yuhao, Li, Jing, Yang, Yingjie, Wu, Daoxiong, Liu, Weifeng, Shen, Yijun, Tian, Xinlong
• Format: Article
• Language: English
• Subjects: butyldithiocarbamate acid; Cadmium sulfide; Charge density; Conduction bands; Density functional theory; Hexagonal phase; Hydrogen evolution; Nanotechnology; phase junction; Photocatalysis; Photocatalysts; photocatalytic hydrogen evolution; Sulfur; sulfur‐rich; Synthesis
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202207623

Photocatalyst with excellent semiconductor properties is the key point to realize the efficient photocatalytic hydrogen evolution (PHE). As a representative binary metal sulfide (BMS) semiconductor, cadmium sulfide (CdS) possesses suitable bandgap of 2.4 eV and negative conduction band potential, which has a great potential to realize efficient visible‐light PHE performance. In this work, CdS with unique cubic/hexagonal phase junction is facilely synthesized through a sulfur‐rich butyldithiocarbamate acid (BDCA) solution process. The results illustrate that the phase junction can efficiently enhance the separation and transfer of photogenerated electron–hole pairs, resulting in an excellent PHE performance. In addition, the sulfur‐rich property of BDCA solution leads to the absence of additional sulfur sources during the synthesis of CdS photocatalyst, which greatly simplifies the fabrication process. The optimal PHE rate of the BDCA‐synthesized phase junction CdS photocatalyst is 7.294 mmol g–1 h–1 and exhibits a favorable photostability. Moreover, density function theory calculations indicated that the apparent redistribution of charge density in the cubic/hexagonal phase junction regions gives a suitable hydrogen adsorption capacity, which is responsible for the enhanced PHE activity. This work designs the cubic/hexagonal phase junction cadmium sulfide (CdS) photocatalyst by a novel sulfur‐rich butyldithiocarbamate acid (BDCA) solution method, which can not only simplify the fabrication complexity but also effectively prevent photocorrosion phenomenon, thus realizes a high hydrogen production rate of 7.294 mmol g–1 h–1 and exhibits a favorable photostability.