Strategic Charge Transfer Regulation in a Bifunctional Heterostructure for Concurrent Photocatalytic Furfural Synthesis and H ₂ Evolution

ABSTRACT Photocatalytic biomass valorization coupled with hydrogen (H ₂ ) evolution offers a sustainable route to simultaneously produce high‐value chemicals and clean energy. However, the efficiency of such bifunctional photosystems is often limited by inefficient charge separation and uncontrolled carrier transfer pathways. In this work, we report the rational design of a Z‐scheme Zn ₃ In ₂ S ₆ /Ti ₃ C ₂ T _x /g‐C ₃ N ₄ heterostructure by incorporating a highly conductive Ti ₃ C ₂ T _x interlayer for selective furfual synthesis and H ₂ generation. The Ti ₃ C ₂ T _x mediator triggers a controllable transition of the charge transfer mechanism from Type II to a Z‐scheme via the formation of Ohmic contacts and dual internal electric fields (IEFs), which promote directional electron flow and suppress recombination. As a result, the optimized photocatalyst achieves a furfural production rate of 0.97 mmol g ⁻¹ h ⁻¹ with nearly 100% selectivity, along with an H ₂ evolution rate of 0.99 mmol g ⁻¹ h ⁻¹ , outperforming most previously reported bifunctional photocatalytic systems. This work demonstrates a strategic approach to steering charge transport in coupled redox photochemistry and opens a viable route for synchronous biomass upgrading and solar fuel production.