Anisotropically Epitaxial P‐N Heterostructures Actuating Efficient Z‐Scheme Photocatalytic Water Splitting

Abstract Crafting anisotropically epitaxial p‐n heterostructures with Z‐scheme charge transmission is a promising avenue toward excellent photocatalytic efficiency, yet the large lattice mismatch and diverse crystal growth habits between components have often arisen as a big challenge to this goal. Here, anisotropically epitaxial p‐n heterostructures with 19.8% lattice mismatch are obtained via a dynamics‐mediated seeded growth tactic under reaction temperature as low as 60 °C. Structural analyses reveal the epitaxy of hexagonal CuS nanoplates onto CdS nanowires through forming misfit dislocations at {101̄0} interface and stacking faults inside CuS nanoplates. Experimental and density functional theory calculation results verify the Z‐scheme photo‐carriers transfer in epitaxial CdS‐CuS heterostructures, which exhibit a much enhanced visible‐light‐driven H 2 generation capability than non‐epitaxial CdS/CuS counterpart, and the site‐specified NiOOH photo‐deposition over CdS‐CuS heterostructures leads to a distinguished H 2 ‐evolving activity ≈65 and 36 times promotion compared to those of pristine CdS and Pt‐loaded (3 wt.%) CdS, respectively. The study can enlighten new thinking to the steerable synthesis of epitaxial nanostructures with large lattice mismatch for various promising applications.