Synthesis of Ternary MoS<sub>2</sub>/Carbon Dots/ZnIn<sub>2</sub>S<sub>4</sub> Nanocomposites for Enhanced Photocatalytic Hydrogen Evolution
Mengyao Geng, Xinyue Wang, Shichang Yuan, Tong Zhao, Jing Zhang, Li Wang, Zhaodong Liu, Meiling Sun, Guangchao Yin
Abstract
The utilization of solar energy for photocatalytic water splitting to generate hydrogen represents a pivotal research domain, with significant implications for ecological and sustainable development. In this investigation, we employed a facile hydrothermal method to synthesize a hierarchical flower-like structure comprising a nonprecious metal ternary MoS 2 /carbon dots (CDs)/ZnIn 2 S 4 heterojunction. Specifically, F-CDs (CDs) and MoS 2 were cultivated on three-dimensional ZnIn 2 S 4 (ZIS) nanoflowers. The photocatalytic activity for hydrogen evolution of the ternary MoS 2 /CDs/ZIS nanocomposite material surpassed that of MoS 2 /ZIS and CDs/ZIS, underscoring a synergistic effect between MoS 2 and CDs in facilitating hydrogen evolution. Furthermore, within the ternary MoS 2 /CDs/ZIS composite material, CDs served as electron mediators, expediting the transfer of photogenerated electrons from the semiconductor-based photocatalyst (ZnIn 2 S 4 ) to the cocatalyst (MoS 2 ). Simultaneously, CDs, functioning as electron acceptors, heightened the hydrogen evolution reaction. The hydrogen production of the MoS 2 /CDs/ZIS(3) composite material reached 13.365 mmol g –1 within a 5 h duration, a notable increase of 6.7 times compared to pure ZIS. This investigation offers a strategic approach for developing efficient hydrogen evolution photocatalysts by leveraging CDs as a bridge to enhance charge transfer in nanocomposite materials.