Dipole synergy enables fast directional charge transport for solar hydrogen and benzaldehyde coproduction

Artificial photosynthesis for hydrogen evolution coupled with benzyl alcohol photoreforming faces efficiency challenges due to insufficient charge directional transfer. Here, we report a synergistic strategy integrating the polarization electric field from asymmetric Zn₃In₄S₉ and the interface dipole field induced by MoS₂ to drive fast charge dynamics. The optimized 6%-MoS₂/Zn₃In₄S₉ exhibits notable photocatalytic performance, generating 41.19 mmol g^-1 h^-1 of hydrogen and 43.33 mmol g^-1 h^-1 of benzaldehyde, which is 11.8 to 12.2 times higher than that of Zn₃In₄S₉. Notably, apparent quantum yields reach 36.6% ± 0.7% for hydrogen and 40.0% ± 0.3% for benzaldehyde (3 times), while retaining 93.8% and 87% of initial activity after 30 hours, demonstrating high stability. In this work, we reveal that the intrinsic dipole of Zn₃In₄S₉ generates a polarization electric field, suppressing bulk charge recombination. Concurrently, the MoS₂-induced interface dipole field creates a fast electron transport pathway from Zn₃In₄S₉ to MoS₂.