Precisely Assembling a CoO Cocatalyst onto Tb 4 O 7 /CN and Pt-Tb 4 O 7 /CN for Promoting Photocatalytic Overall Water Splitting.

Photocatalytic overall water splitting (POWS) is a promising approach for solar-to-hydrogen conversion. For achieving this target, it is urgent to develop efficient photocatalysts. Constructing a heterojunction and loading a cocatalyst are two effective strategies for enhancing POWS. However, how to achieve the cooperation of loading the cocatalyst site with the charge separation of a heterojunction remains a huge challenge. Herein, we present an ingenious method: precisely assembling a H 2 O 2 -producing cocatalyst CoO on Tb 4 O 7 /CN. Assembling CoO on CN of Tb 4 O 7 /CN improves the photoinduced electron-hole pair separation and promotes the POWS performance. Inversely, engineering CoO on Tb 4 O 7 leads to production of Co, deactivating POWS performance with a H 2 -evolution rate 5.2 times lower than that of Tb 4 O 7 /CN. Furthermore, we precisely assemble CoO on the CN section of Pt-oriented Pt-Tb 4 O 7 /CN. The bioriented CoO and Pt cooperatively promote photogenerated carrier separation. Consequently, the prepared Pt-Tb 4 O 7 /CN-CoO exhibits spectacularly high POWS activity. The H 2 -evolution rate reaches 450 μmol h -1 g -1 , which is about 9.4 times higher than that of the initial Tb 4 O 7 /CN. The apparent quantum yield (AQY) for H 2 evolution at 420 nm reaches 14.1%, surpassing those of most reported CN-based photocatalysts. This work offers an approach to precisely load cocatalysts on heterojunctions. These findings provide insights for designing cocatalyst-decorated heterojunctions for POWS.