Preparation of Z‐Type Co₂SnO₄/Mn_0.5Cd_0.5S Heterojunction for Efficient Piezo‐Photocatalytic Hydrogen Production

ABSTRACT Although conversion of solar‐energy for catalytic water splitting into H 2 is promising technology, the sluggish charge separation in photocatalytic process severely restricts the activity. Combining the piezoelectric effect of piezoelectric materials with the load cocatalyst strategy can effectively modulate the transport behavior of carriers. Herein, a novel and efficient Co 2 SnO 4 cocatalyst is loaded onto Mn x Cd 1‐x S (x = 0.2, 0.3, 0.4, 0.5, 0.6, 0.7) piezoelectric material to form a heterostructure for piezo‐photocatalytic hydrogen evolution. To the best of our knowledge, Co 2 SnO 4 has not been reported as a cocatalyst in the field of piezoelectric photocatalysis. The 7% Co 2 SnO 4 /Mn 0.5 Cd 0.5 S (CSO/MCS) exhibits excellent piezoelectric‐photocatalytic hydrogen production rate (29.86 mmol/g/h) under the condition of light coupling ultrasound, which is significantly superior to piezoelectric catalysis (128.35 μmol/g/h) and photocatalysis (9.25 mmol/g/h). The built‐in electric field in Mn 0.5 Cd 0.5 S piezo‐photocatalyst and the Z‐type heterojunction made up of the tight connection of Co 2 SnO 4 and Mn 0.5 Cd 0.5 S both promote the carrier separation efficiency, thereby improving the catalytic reaction performance. This work manifests a promising approach to design heterojunction catalysts for efficient renewable fuel production by capturing solar and mechanical energy.