Constructing an Open-Structured J-Type ZnIn₂S₄/In(OH)₃ Heterojunction for Photocatalytical Hydrogen Generation

Constructing heterojunctions to separate photogenerated carriers is an effective strategy for improving the efficiency of photocatalytic reactions. A J-type heterojunction is a recently reported efficient anisotropic heterojunction. Herein, taking anisotropic ZnIn₂S₄ (ZIS) nanosheets as an example of a type-II heterojunction, we report for the first time the concept of open and closed structures (O and C structure) of J-type heterojunctions. A simple ammonia-post-treatment method was employed to prepare the O- and C-structured J-type ZnIn₂S₄/In(OH)₃ (ZIS/IOH) heterojunctions. The O-structured J-type ZIS/IOH (OJ-ZIS/IOH) heterojunction exhibits a high hydrogen production activity, reaching 400 μmol·h^-1, 2.67 times higher than that of pristine ZIS. However, the activity of the C-structured heterojunction (CJ-ZIS/IOH) is close to that of pristine ZIS. The findings emphasize the importance of the cooperation of photogenerated carrier separation and transport in J-type heterojunctions, providing insights into developing efficient heterojunction photocatalysts.