内容提要: |
Extended Abstract
As a clean and renewable energy source, hydrogen is considered as an emerging supplementary energy source that can replace the fossil fuel with the deterioration of the environment and the depletion of fossil fuel [1]. With the development of hydrogen production technology, photocatalytic hydrogen evolution was thought as the most promising technology for hydrogen energy development, although it was still limited by the solar energy utilization and efficient charge separation capability of photocatalysts [2]. How to promote * H adsorption through the modulation of electronic structure and defective sites is of great significance for photocatalytic hydrogen evolution. 1T-phase transition metal sulfides (TMDs) have been widely used as co-catalysts in photocatalysis and thermal catalysis with the potential to replace noble metals due to their ultra-high conductivity and abundant substrate active sites. Stanley S. Chou et al [3]. first demonstrated that metal 1T-MoS2 could serve as excellent photothermal agents. Cui et al [4]. used S vacancies defect excitation to modulate the inert substrate surface of 1T-WS2 for electrocatalytic hydrogen evolution. However, studies on the application of S vacancies 1T-WS2 as a co-catalyst for photocatalytic hydrogen evolution are relatively lacking. Here we considered the potential of metal 1T-WS2 to promote charge migration kinetics acceleration by photothermal effect. The S vacancies 1T-WS2 was used as a co-catalyst to provide a platform for efficient carrier trapping and *H adsorption.
In this work, we designed an S vacancies 1T-WS2/CdS to achieve 70.9 mmol/g/h hydrogen evolution rate accompanied with 39.1% AQY at 500 nm via coordinating the interfacial electronic engineering and photothermal effect. The photothermal effect induced by S vacancies 1T-WS2 effectively lowered the apparent activation energy from 15.96 kJ/mol to 10.51 kJ/mol, meanwhile, the directional migration of electrons from CdS to S vacancies accelerated by lattice heating was the main reason for boosting photocatalytic hydrogen evolution. Both the decrease of free energy of *H due to the existence of S vacancies and the enhancement of field strength caused by effective enrichment of electrons at the interface of S vacancies 1T-WS2/CdS. This work provided valuable insight into the use of non-precious metal co-catalysts for photo-thermal assisted photocatalytic hydrogen evolution. |