Single-Atom Metal Anchored Zr6-Cluster-Porphyrin FrameworkHollow Nanocapsules with Ultrahigh Active-Center Density forElectrocatalytic CO2Reduction

Designing earth-abundant electrocatalysts toward highly efficient CO2reduction has significant importance todecrease the global emission of greenhouse gas. Herein, we propose an efficient strategy to anchor non-noble metal single atoms onZr6-cluster-porphyrin framework hollow nanocapsules with well-defined and abundant metal-N4porphyrin sites for efficientelectrochemical CO2reduction. Among different transition metal single atoms (Mn, Fe, Co, Ni, and Cu), Co single-atom anchoredZr6-cluster-porphyrin framework hollow nanocapsules demonstrated the highest activity and selectivity for CO production. The richCo-N4active centers and hierarchical porous structure contribute to enhanced CO2adsorption capability and moderate bindingstrength of reaction intermediates, thus facilitating*CO desorption and CO2-to-CO conversion. The Co-anchored nanocapsulesmaintain high efficiency and well-preserved stability during long-term electrocatalysis tests. Moreover, the Co-anchorednanocapsules exhibit a remarkable solar-to-CO energy conversion efficiency of 12.5% in an integrated solar-driven CO2reduction/O2evolution electrolysis system when powered by a custom large-area [Cs0.05(FA0.85MA0.15)0.95]Pb0.9(I0.85Br0.15)3-basedperovskite solar cell.

Automated summary

Designing earth-abundant electrocatalysts for efficient CO2 reduction is important for reducing global greenhouse gas emissions. This study presents a strategy to anchor non-noble metal single atoms on Zr6-cluster-porphyrin framework hollow nanocapsules, enabling efficient electrochemical CO2 reduction. Among different transition metals, Co single-atom anchored nanocapsules showed the highest activity and selectivity for CO production. The Co-anchored nanocapsules maintain high efficiency and stability during long-term electrocatalysis tests and demonstrate remarkable solar-to-CO energy conversion efficiency in an integrated solar-driven CO2 reduction/O2 evolution electrolysis system.