Bismuth Chalcogenide-Based Photocatalysts for Nitrogen Reduction: Recent Progress and Prospects

Area of Science:

• Materials Science
• Catalysis
• Photochemistry

Background:

• Bismuth chalcogenides are emerging as efficient photocatalysts for nitrogen reduction reaction (NRR).
• Their unique electronic structures, visible-light activity, and tunable bands aid nitrogen adsorption and activation.
• The stereochemically active Bi 6s² lone pair is crucial for these properties.

Purpose of the Study:

• To review recent advancements in designing bismuth chalcogenide-based photocatalysts for light-driven ammonia synthesis.
• To critically discuss fundamental aspects of photocatalytic N₂ reduction and ammonia quantification.
• To analyze material engineering strategies for improved photocatalytic performance.

Main Methods:

• Review of literature on bismuth chalcogenide photocatalysts for NRR.
• Analysis of material engineering strategies: defect modulation, doping, heterojunctions (Type-II, Z-scheme, S-scheme), and hybrid structures.
• Discussion of charge separation, band alignment, and ammonia quantification methods.

Main Results:

• Various material engineering strategies significantly impact charge separation and band alignment.
• Heterojunctions (Type-II, Z-scheme, S-scheme) and hybrid structures offer enhanced photocatalytic activity.
• Defect modulation and elemental doping provide routes for tuning material properties.

Conclusions:

• Bismuth chalcogenide photocatalysts offer a sustainable route for ammonia synthesis.
• Challenges include low N₂ activation, competing hydrogen evolution, and charge recombination.
• Future research should focus on electronic structure, mechanistic studies, and standardized protocols.