Formation\nof Hierarchical In₂S₃–CdIn₂S₄ Heterostructured Nanotubes\nfor Efficient and Stable Visible Light CO₂ Reduction

Abstract

We demonstrate rational design and\nfabrication of hierarchical In₂S₃-CdIn₂S₄ heterostructured nanotubes as efficient and stable\nphotocatalysts for visible light CO₂ reduction. The novel\nself-templated strategy, including sequential anion- and cation-exchange\nreactions, integrates two distinct sulfide semiconductors into hierarchical\ntubular hybrids with homogeneous interfacial contacts and ultrathin\ntwo-dimensional (2D) nanosheet subunits. Accordingly, the hierarchical\nheterostructured nanotubes facilitate separation and migration of\nphotoinduced charge carriers, enhance the adsorption and concentration\nof CO₂ molecules, and offer rich active sites for surface\nredox reactions. Benefiting from these structural and compositional\nfeatures, the optimized hierarchical In₂S₃-CdIn₂S₄ nanotubes without employing noble metal cocatalysts\nin the catalytic system manifest remarkable performance for deoxygenative\nreduction of CO₂ with high CO generation rate (825 μmol\nh^–1 g^–1) and outstanding stability\nunder visible light irradiation.