Boosted Scavenger‐Free Overall Nitrogen Photofixation with Molybdenum Incorporated Bismuth‐Rich Oxychlorides

Abstract The design of highly efficient photocatalysts to photoreduce nitrogen (N₂) to ammonia (NH₃) under mild conditions is extremely challenging. In this work, various molar ratio of molybdenum (Mo) is incorporated into Bi₁₂O₁₇Cl₂ via a hydrothermal process. The resulting Mo‐doped Bi₁₂O₁₇Cl₂ exhibits remarkable solar‐driven activity for N₂ photo fixation without any scavengers or sacrificial agents. The optimal sample with 5% Mo dopants displays an NH₃ yield of 39.83 µmol g⁻¹ h⁻¹, a 1.6‐fold improvement over undoped pristine Bi₁₂O₁₇Cl₂. The impressive performance is attributed to the synergistic effects of oxygen vacancies (OVs) and Mo‐loading, enhancing light absorption and extending photo‐response through band gap reduction. Additional contributions arise from the enriched active sites, facilitating N₂ adsorption and electron transport to the reactants. Density functional theory calculations reveal that Mo integration induces significant charge redistribution around the active sites, thereby reducing the energy barrier associated with N₂ activation and protonation. In‐depth investigation into the reaction pathway unravels the step‐by‐step reaction process which further elucidates the beneficial role of Mo loading in the overall N₂ photoconversion process. As a whole, this work promotes a simple and effective engineering approach based on heteroatom doping as an efficacious strategy to design highly active photocatalysts toward N₂ photo fixation.