Valence State Engineering of Cobalt in Zeolite Imidazole Frames‐67 via Redox Modulation for Enhanced Photocatalytic Degradation of Atrazine

The effectiveness of metal catalytic sites is heavily dependent on their surrounding coordination structure. Nevertheless, accurately controlling and finely adjusting these coordination environments remains a considerable challenge. Herein, an innovative strategy is proposed through oxidation state modulation to tailor the coordination configurations of cobalt sites in zeolite imidazole frames (ZIF)‐derived metal–organic frameworks (MOFs). Systematic degradation experiments, combined with X‐ray photoelectron spectroscopy analysis, reveal that ZIF‐67 treated with strong oxidizing or reducing agents achieves remarkably enhanced photoactivity. This is attributed to the regulation of the Co 2+ /Co 3+ ratio, which promotes rapid electron transfer, generates abundant photoinduced free radicals, and significantly improves the efficiency of pollutant decomposition. It is noteworthy that the tailored ZIF‐67 catalysts exhibit greater adsorption performance and boost photocatalytic effectiveness in atrazine (ATZ) removal. Under dark conditions, H10 and N10 demonstrate adsorption performance of 40.5 and 41 mg g −1 , respectively, significantly higher than pristine ZIF‐67 (2 mg g −1 ). Upon photocatalytic reactions, the ATZ concentration is further reduced to 13%–15% for H10 and N10, compared to 50% for ZIF‐67. This study offers a dependable experimental approach for modulating the oxidation states of metal active sites within MOFs.