β-NiS modified CdS nanowires for photocatalytic H2 evolution with exceptionally high efficiency
Shundong Guan1,2, Xiuli Fu1, Yu Zhang1,2,3
1State Key Laboratory of Information Photonics and Optical Communications , School of Science , Beijing University of Posts and Telecommunications , Beijing 100876 , P. R. China . Email: xiulifu@bupt.edu.cn ; ; Tel: +86-10-62282452.
Chemical Science
|April 21, 2018
Summary
Developing novel semiconductor photocatalysts is key for efficient hydrogen evolution. This study presents a simple method to create highly active β-NiS modified CdS nanowires (NiS/CdS NWs) for enhanced hydrogen production.
Area of Science:
- Materials Science
- Photocatalysis
- Nanotechnology
Background:
- Co-catalysis is a vital strategy for enhancing semiconductor photocatalyst performance in hydrogen evolution.
- Achieving optimal synergy between co-catalysts and host photocatalysts remains a significant challenge.
- Developing efficient and scalable synthesis methods for hybrid photocatalysts is crucial.
Purpose of the Study:
- To synthesize novel hybrid photocatalysts (NiS/CdS NWs) using a simple and green hydrothermal route.
- To investigate the effect of β-NiS co-catalyst loading on the photocatalytic hydrogen evolution activity of CdS nanowires.
- To elucidate the mechanism behind the enhanced photocatalytic performance.
Main Methods:
- Synthesis of CdS nanowires (CdS NWs) using a hydrothermal route.
- Modification of CdS NWs with β-NiS nanostructures via an electroless plating process assisted by sodium hypophosphite.
- Characterization of the synthesized NiS/CdS NWs.
- Evaluation of photocatalytic hydrogen evolution activity under visible light irradiation in lactic acid aqueous solutions.
Main Results:
- Successfully synthesized β-NiS modified CdS nanowires (NiS/CdS NWs) with highly conducting, flake-like β-NiS nanostructures.
- Achieved a record-high photocatalytic activity for H2 evolution, with a rate of 793.6 μmol h-1 (over 5 mg catalyst) at 25 °C, nearly 250-fold higher than pure CdS NWs.
- Attained an exceptionally high apparent quantum yield of 74.1% at 420 nm, demonstrating superior visible light utilization.
- Proposed a mechanism for the enhanced photocatalytic hydrogen evolution over the NiS/CdS NWs heterostructure.
Conclusions:
- The developed hydrothermal route provides a simple and green method for synthesizing high-performance NiS/CdS NWs.
- The optimized NiS/CdS NWs exhibit remarkable photocatalytic activity and efficiency for hydrogen evolution under visible light.
- This strategy offers new insights into designing and developing advanced heterostructured photocatalysts for energy applications.
