Formation of hierarchical FeCoS₂–CoS₂ double‐shelled nanotubes with enhanced performance for photocatalytic reduction of CO₂

• Main Authors: Wang, Yan, Wang, Sibo, Zhang, Song Lin, Lou, David Xiong Wen
• Other Authors: School of Chemical and Biomedical Engineering
• Format: Article
• Language: English
• Published: 2023
• Subjects: Engineering::Chemical engineering; Heterostructures; Metal Sulfides
• Online Access: https://hdl.handle.net/10356/170449
• Institution: Nanyang Technological University

Hierarchical FeCoS2–CoS2 double-shelled nanotubes have been rationally designed and constructed for efficient photocatalytic CO2 reduction under visible light. The synthetic strategy, engaging the two-step cation-exchange reactions, precisely integrates two metal sulfides into a double-shelled tubular heterostructure with both of the shells assembled from ultrathin two-dimensional (2D) nanosheets. Benefiting from the distinctive structure and composition, the FeCoS2–CoS2 hybrid can reduce bulk-to-surface diffusion length of photoexcited charge carriers to facilitate their separation. Furthermore, this hybrid structure can expose abundant active sites for enhancing CO2 adsorption and surface-dependent redox reactions, and harvest incident solar irradiation more efficiently by light scattering in the complex interior. As a result, these hierarchical FeCoS2–CoS2 double-shelled nanotubes exhibit superior activity and high stability for photosensitized deoxygenative CO2 reduction, affording a high CO-generating rate of 28.1 μmol h−1 (per 0.5 mg of catalyst).