Twisted BiOCl Moiré Superlattices for Photocatalytic Chloride Reforming of Methane

Abstract

Solar-driven conversion of CH₄ into value-added methyl chlorides and H₂ with abundant chloride ions offers a sustainable CH₄ reforming strategy but suffers from inefficient Cl^– activation and severe e^––h⁺ recombination in traditional photocatalysts. Herein, we demonstrate that BiOCl moiré superlattices with a 11.1° twist angle are highly efficient for photocatalytic CH₄ reforming into CH₃Cl and H₂ with NaCl. These moiré superlattices, featuring misalignment-induced tensile strains, destabilize surface Bi–Cl bonds, facilitating a hole-mediated MvK-analogous process to activate lattice Cl into reactive ^•Cl for CH₄ chlorination. Meanwhile, their twisted stacking configurations reinforce interlayer electronic coupling and thus accelerate out-of-plane carrier transfer. Along with surface anchoring of single-atom Pt sites for H₂ evolution, the resulting Pt₁/BiOCl moiré superlattices deliver a CH₃Cl yield of 53.4 μmol g^–1 h^–1 with an impressive selectivity of 96% under visible light. This study highlights the potential of lattice engineering in two-dimensional photocatalysts to regulate structural strains and carrier dynamics for the decentralized reforming of CH₄.