Facet‐Engineered S‐Scheme Heterostructure With Enhanced Active Sites for Efficient Photocatalytic Degradation of Organic Contaminants

ABSTRACT Heterostructured photocatalysts can effectively facilitate the degradation of detrimental organic contaminants in wastewater, particularly bisphenol A (BPA) and methylene blue (MB); however, their catalytic performance often remains limited. Herein, we construct an S‐scheme ZnO/Zn ₃ In ₂ S ₆ (ZnO/ZIS) heterostructure with extensive interfacial coupling between the {001} facets of both phases. The distinct work functions and high surface atom densities of {001} ZnO and {001} ZIS generate elongated Zn─O bridges at the interface, facilitating directional charge migration along the S‐scheme pathway. Concurrently, abundant accessible Zn active sites and optimized adsorption toward pollutant molecules enhance photocatalytic efficiency. These structural and electronic features are confirmed via comprehensive in situ and ex situ characterizations, including scanning transmission electron microscopy, electron paramagnetic resonance, X‐ray absorption, and X‐ray photoelectron spectroscopy, supported by theoretical simulations. As a result, the heterostructure achieves remarkable mineralization rates of ∼86% for BPA and ∼96% for MB within a short treatment time, achieving rapid and thorough degradation without forming significant carbon‐based intermediates. This work demonstrates a feasible crystal‐plane engineering strategy for designing advanced photocatalysts for efficient wastewater purification.