An ion-exchange strategy for I-doped BiOCOOH nanoplates with enhanced visible light photocatalytic NOx removal

A simple ion-exchange method was developed for I-doped BiOCOOH nanoplates from the replacement of COOH-ions with I-ions in the interlayers of BiOCOOH. The as-prepared catalysts were characterized by XRD, SEM, TEM, XPS, UV-vis DRS PL and photocurrent generation. The photocatalytic activity of the as-prepared catalysts was evaluated by removal of NO in air at ppb level under visible light irradiation. As expected, the I-doped BiOCOOH (IHB-X, the X represents the molar ratio of KI to BiOCOOH) displayed increased visible light absorption and enhanced charge separation due to I-doping. At a saturate I-doping content, the IHB-1.00 catalyst with optimized electronic structure demonstrated the highest NO removal of 49.7 % and excellent photochemical stability. This present work has demonstrated a new strategy for modification of layered photocatalyst via ion exchange.