Operating redox couple transport mechanism for enhancing photocatalytic H2 generation of Pt and CrOx-decorated ZnCdS nanocrystals

Metal sulfide photocatalysts have been leading edge for hydrogen evolution reaction (HER) and solar energy conversion due to their suitable electronic and optical properties. The efficiency of these photocatalysts is mostly restricted by slow transfer of photogenerated holes and sluggish water dissociation kinetics. Here, we proposed HER catalyst comprising of Pt-CrO x sites loaded on ZnCdS nanocrystal (ZnCdS/Pt-CrO x ) that employing a redox couple ( OH/OH − ) transport mechanism to efficiently relay of holes in alkaline media. The Pt sites provide optimal hydrogen adsorption energy and CrO x sites support water dissociation, which speed up water dissociation kinetics and leads to a noticeable enhance in HER (21.1 mmol g −1  h −1 ) and phenol degradation. Such efficient activity could be associated to a better mobility of redox couple and fast water dissociation kinetics in alkaline solution. These types of related works open pathways to generate hydrogen from the sea water, largest water source on earth.