标题：WS2/Graphitic Carbon Nitride Heterojunction Nanosheets Decorated with CdS Quantum Dots for Photocatalytic Hydrogen Production
作者：Zou, Yajun; Shi, Jian-Wen; Ma, Dandan; Fan, Zhaoyang; Cheng, Linhao; Sun, Diankun; Wang, Zeyan; Niu, Chunming
作者机构：[Zou, Yajun; Shi, Jian-Wen; Ma, Dandan; Fan, Zhaoyang; Cheng, Linhao; Sun, Diankun; Niu, Chunming] Xi An Jiao Tong Univ, Sch Elect Engn, Ctr Nanomat R 更多
通讯作者地址：[Shi, JW]Xi An Jiao Tong Univ, Sch Elect Engn, Ctr Nanomat Renewable Energy, State Key Lab Elect Insulat & Power Equipment, Xian 710049, Shaanxi, Peop 更多
关键词：interfaces; photochemistry; quantum dots; semiconductors; water; splitting
摘要：Two-dimensional/two-dimensional (2D/2D) stacking heterostructures are highly desirable in fabricating efficient photocatalysts because face-to-face contact can provide a maximized interfacial region between the two semiconductors; this largely facilitates the migration of charge carriers. Herein, a WS2/graphitic carbon nitride (CN) 2D/2D nanosheet heterostructure decorated with CdS quantum dots (QDs) has been designed, for the first time. Optimized CdS/WS2/CN without another cocatalyst exhibits a significantly enhanced photocatalytic H-2 evolution rate of 1174.5 mu molh(-1)g(-1) under visible-light irradiation (lambda > 420 nm), which is nearly 67 times higher than that of the pure CN nanosheets. The improved photocatalytic activity can be primarily attributed to the highly efficient charge-transfer pathways built among the three components, which effectively accelerate the separation and transfer of photogenerated electrons and holes, and thus, inhibit their recombination. Moreover, the extended light-absorption range also contributes to excellent photocatalytic efficiency. In addition, the CdS/WS2/CN photocatalyst shows excellent stability and reusability without apparent decay in the photocatalytic H-2 evolution within 4 cycles in 20 h. It is believed that this work may shed light on specifically designed 2D/2D nanosheet heterostructures for more efficient visible-light-driven photocatalysts.