Interfacial Chemical-Bonded MoS<sub>2</sub>/In–Bi<sub>2</sub>MoO<sub>6</sub> Heterostructure for Enhanced Photocatalytic Nitrogen-to-Ammonia Conversion
Taoxia Ma, Ruqi Li, Yucheng Huang, Yuxuan Lu, Li Guo, Maomao Niu, Xin Huang, Razium Ali Soomro, Jingyu Ren, Qi Wang, Bin Xu, Chunming Yang, Feng Fu, Danjun Wang
Abstract
Photocatalytic nitrogen reduction reaction (pNRR) is considered an ideal NH 3 synthetic technology. Although catalysts prepared for pNRR under mild conditions have been extensively developed, they still face limitations of insufficient N 2 adsorption/activation and low NH 3 selectivity. Herein, a MoS 2 /In–Bi 2 M O O 6 heterojunction catalyst with an interfacial chemical bond was constructed by the electrostatic self-assembly method. Efficient spatial separation of photogenerated electron/hole pairs and accelerated carrier transfer dynamics were facilitated due to the formation of a Mo–S bond at the interface between MoS 2 and In–Bi 2 MoO 6 . The crystal orbital Hamiltonian population (COHP) analysis further confirmed that the electrons transferred from MoS 2 into the antibonding orbital of N 2 to activate the adsorbed N 2, favoring nitrogen-to-ammonia (N 2 -to-NH 3 ) conversion. The resultant NH 3 /NH 4 + production rate for 3% MoS 2 /In–Bi 2 MoO 6 reached 90 μmol·g –1 ·h –1, representing a significant improvement over pure Bi 2 MoO 6, while the production of NO 3 – was minimal. Introducing MoS 2 as a cocatalyst effectively inhibited the oxidation of NH 3 /NH 4 + to NO 3 –, achieving selective pNRR. This work provides a foundation for selective photocatalytic nitrogen fixation, offering valuable insights into the clean production of NH 3 .