Z-scheme 2D/2D heterojunction of ZnIn2S4/Ti-BPDC enhancing photocatalytic hydrogen evolution under visible light irradiation

Two-dimensional (2D) lamellar materials have an appealing prospect in the field of photocatalysis due to their ultrathin thickness and exposed reactive sites. The regulation of photogenerated carrier transfer is more conducive to further enhancing catalytic performance. Herein, a direct Z-scheme 2D/2D heterojunction of ZnIn2S4/Ti-BPDC was synthesized using a simple electrostatic self-assembly process. The morphology of the ultrathin lamellar endows the catalyst with more exposed active sites and a short charge transfer distance. The large contact interface and intimate interaction between the two semiconductors ensure a smooth interphase electron transport channel. The matching of staggered band structures provides the basis for constructing an internal electric field and band bending to realize Z-scheme charge transfer. Benefiting from the combined effects of these aspects, ZnIn2S4/Ti-BPDC showed substantially enhanced interface photogenerated carrier transfer efficiency and photocatalytic hydrogen evolution performance. Moreover, the 2D/2D ZnIn2S4/Ti-BPDC heterojunction possessed excellent stability and recyclability, showing potential for applications in sustainable energy conversion.