Photocatalytic H<sub>2</sub> Evolution from Ammonia Borane: Improvement of Charge Separation and Directional Charge Transmission
Sishi Zhang, Jie Xu, Hongmei Cheng, Cuicui Zang, Fengxia Bian, Bin Sun, Yu Shen, Heyan Jiang
Abstract
Abstract Co/M II Fe layered double hydroxide (LDH) LDH photocatalysts have been designed from the aspect of employing stable half‐filled Fe 3+ to trap photogenerated electrons, adjusting the M II −O−Fe oxo‐bridged structure to optimize the short‐range directional charge transmission and intercalating oxometallate anions into the LDH to further improve light absorption along with electron‐hole separation and non‐noble metal Co NP loading and reduction to form a heterojunction. These LDH‐based photocatalysts are employed for photocatalytic H 2 evolution from ammonia borane in aqueous solution under visible light at 298 K. The photocatalytic H 2 evolution activity is greatly improved through adjustment of the M II −O−Fe oxo‐bridged structure and molybdate intercalation into the LDH. Turnover frequencies of up to 113.2 min −1 are achieved with Co/CoFe−Mo. Alongside the experimental results and materials characterization, capture experiments and in situ DRIFTS analysis are carried out to study the photocatalytic hydrogen production mechanism.