CoTCPP‐Modified Bi 19 S 27 Br 3 for Efficient Photocatalytic Nitrate Reduction to Ammonia

Photocatalytic nitrate reduction to ammonia holds dual significance for nitrogen‐containing wastewater remediation and green ammonia synthesis. However, single‐component semiconductor photocatalysts are generally hampered by severe photogenerated charge recombination, insufficient spectral response, and poor substrate activation. Herein, cobalt porphyrin (CoTCPP) was in situ anchored onto the surface of Bi 19 S 27 Br 3 nanorods via a solvothermal method to construct CoTCPP/Bi 19 S 27 Br 3 photocatalysts featuring strong interfacial coupling. X‐ray photoelectron spectroscopy (XPS) analysis reveals a distinct interfacial electronic coupling between CoTCPP and Bi 19 S 27 Br 3 . This strong interfacial coupling synergistically enhances photocatalytic performance by facilitating rapid capture and efficient interfacial transfer of photogenerated electrons to effectively suppress charge carrier recombination, significantly broadening the near‐infrared (NIR) light response range, and strengthening the electrostatic adsorption of NO 3 − on the catalyst surface to accelerate the selective generation of NH 3 . The optimized 1.5CoTCPP/Bi 19 S 27 Br 3 achieved an NH 3 production rate of 1230.81 μmol·g −1 ·h −1 , approximately 5‐fold higher than that of pristine Bi 19 S 27 Br 3 . In situ Fourier transform infrared spectroscopy confirmed the stepwise deoxygenation–hydrogenation reduction pathway of NO 3 − → *NO 3 → *NO 2 → *NO → *NHOH → *NH 2 OH → NH 3 . This work provides an effective strategy for constructing interfacially coupled photocatalytic systems toward efficient nitrate reduction to ammonia.