Robust visible-light photocatalytic H evolution on 2D RGO/CdZnInS-NiP hierarchitectures

Photocatalytic water-splitting to produce hydrogen (H 2 ) is considered one of the most promising strategies to solve the increasing energy and environmental challenges facing humanity. However, the major obstacle is the lack of highly efficient photocatalysts with visible-light absorption capability and prominent charge transfer and separation. Herein, we developed for the first time an interface-engineered 2D hierarchitecture comprising ultrathin Cd-doped ZnIn 2 S 4 (Cd 0.15 Zn 0.85 In 2 S 4 ) nanosheets coupled with Ni 2 P nanoparticles as a cocatalyst and reduced graphene oxide (RGO) nanosheets as an electron mediator. Under visible-light ( λ > 400 nm) irradiation, the RGO/Cd 0.15 Zn 0.85 In 2 S 4 -Ni 2 P composite displayed an enhanced H 2 evolution activity of 14.56 mmol h −1 g −1 that is 22 times that of pristine ZnIn 2 S 4 , and much higher than those of RGO/Cd 0.15 Zn 0.85 In 2 S 4 , Cd 0.15 Zn 0.85 In 2 S 4 -Ni 2 P, Pt-loaded RGO/Cd 0.15 Zn 0.85 In 2 S 4 , and many previously reported ZnIn 2 S 4 -based photocatalysts. Additionally, the RGO/Cd 0.15 Zn 0.85 In 2 S 4 -Ni 2 P hybrids showed outstanding long time cycling stability. The excellent photocatalytic HER capability of our photocatalyst could be attributed to the enhanced light-harvesting capability of porous hierarchitectures, increased charge transfer and separation via the interface-engineered Schottky heterojunctions, and the many active sites of the Ni 2 P cocatalyst. The synergistic cooperation of the cocatalyst and electron mediator in 2D nanostructures offers a promising approach to prepare efficient solar photocatalysts. Unique 2D ternary hierarchitectures constructed from reduced graphene oxide nanosheets grown with ultrathin Cd 0.15 Zn 0.85 In 2 S 4 nanosheets and Ni 2 P nanoparticles exhibited an outstanding capability for visible-light photocatalytic H 2 production.