Boosting photocatalytic hydrogen production in complex environments by confining trace MoBT_x MBene

Area of Science:

• Materials Science
• Catalysis
• Nanotechnology

Background:

• Charge carrier recombination limits semiconductor photocatalysis.
• Defect engineering and heterostructures can improve hydrogen intermediate (*H) adsorption for enhanced photocatalytic hydrogen evolution reaction (HER).

Purpose of the Study:

• To design a defective MoBTx/CdS heterostructure for improved photocatalytic HER.
• To investigate the role of Mo vacancies and interfacial Mo-S bonds in enhancing catalytic performance.

Main Methods:

• Controlled etching of MoBTx to create defects.
• In situ hydrothermal assembly of MoBTx/CdS heterostructures.
• Photoelectrochemical and computational analyses to elucidate reaction mechanisms.

Main Results:

• A MoBTx/CdS catalyst with 0.5 wt% MoBTx exhibited a fourfold increase in HER activity compared to bare CdS.
• Achieved HER of 10.2 mmol/g/h with 23.2% apparent quantum yield, maintaining 90.2% activity after 24 hours.
• Demonstrated excellent environmental adaptability in tap water (7.1 mmol/g/h) and seawater (5.7 mmol/g/h), with robust performance across temperatures (5-35°C).

Conclusions:

• Defective MoBTx/CdS heterostructures significantly enhance photocatalytic HER.
• Mo vacancies optimize band alignment, reduce *H adsorption barriers, and improve carrier separation.
• Interfacial covalent Mo-S bonds facilitate rapid electron transfer, establishing a new paradigm for photocatalyst design.