Visible light active ZnIn2S4/g-C3N4 heterostructure nanocomposite photoelectrode for efficient photoelectrochemical water splitting activity

Hexagonal zinc indium sulfide coupled g-C3N4 (H-ZnIn2S4/g-C3N4) nanocomposites were synthesized using chemisorption method and its performance towards photoelectrochemical water splitting activity was studied. The H-ZnIn2S4/g-C3N4 (H-ZIS/CN) nanocomposites exhibited ti 1.9 times enhanced photo-electrochemical performance as compared to the H-ZnIn2S4. The enhancement in the PEC water splitting activity of H-ZIS/CN nanocomposite is ascribed to the formation of type-II heterojunction which resulted in improved separation of photogenerated charge carriers and faster transfer of charges at the photoelec-trode/electrolyte interface. The electrochemical impedance study and Mott-Schottky supported these results. Moreover, during photoelectrochemical reactions, H-ZIS/CN nanocomposites showed tremen-dous stability under visible light. A potential mechanism of the enhanced photoelectrochemical activity of H-ZIS/CN nanocomposites was proposed and endorsed by the PEC results. This study demonstrates that establishing a heterostructure system by coupling a ternary chalcogenide semiconductor with a con-ducting polymer is an effective strategy for PEC water splitting applications. (c) 2023 Published by Elsevier B.V. on behalf of The Society of Powder Technology Japan.

Automated summary

Hexagonal zinc indium sulfide coupled g-C3N4 (H-ZnIn2S4/g-C3N4) nanocomposites were synthesized via chemisorption method, and their photoelectrochemical water splitting activity was investigated. The H-ZnIn2S4/g-C3N4 nanocomposites exhibited a 1.9 times higher photoelectrochemical performance than H-ZnIn2S4. The improved performance can be attributed to the formation of a type-II heterojunction, which enhances the separation and transfer of photogenerated charge carriers.