Bismuth Gadolinium Oxychloride with a Remarkable Visible-Light-Responsive O₂ Evolution Activity Promoted by Iodine...

Visible-light-responsive bismuth-based oxyhalide has recently attracted extensive attention, however, the promotion of its charge separation is still challenging. Herein, we introduce iodine into Bi₂ GdO₄ Cl to synthetize I-doped Bi₂ GdO₄ Cl (denoted as yI-Bi₂ GdO₄ Cl, 0≤y≤2). The incorporation of I^- ions is found to enhance light absorption and to accelerate charge separation by combining various characterizations such as density functional theory calculation, photoelectrochemical test, electrochemical impedance spectroscopy, photoluminescence spectrum, and open-circuit voltage decay. The O₂ -evolving performances of 1I-Bi₂ GdO₄ Cl with optimized dopant concentration of I^- ion and IrO₂ loaded 1I-Bi₂ GdO₄ Cl are tremendously enhanced by ca. 4 and 45 times compared to pristine Bi₂ GdO₄ Cl. Notably, The O₂ evolution rate reaches as high as 154.8 μmol ⋅ h^-1 with an apparent quantum efficiency of ∼1.1 % at 420 nm. The synthetic iodine-doped photocatalyst remains stable after long-term photoreaction, demonstrating its potential in the field of photocatalysis.