Antireconstruction Cu Nanowire Catalysts Enabled by SiO<sub>2</sub> Encapsulation for Durable Electrochemical CO<sub>2</sub> Reduction
Xiaodong Wen, Qizhi Min, Xiaodong Liu, Gang Zhao, Junyao Wang, Qinshang Xu, Guoshuai Shi, Liming Zhang, Wenhua Zhang, Yude Su
Abstract
Structural reconstruction─an uncontrollable process that compromises the stability of Cu-based catalysts in electrochemical CO 2 reduction (CO 2 R)─presents a major scientific challenge that has yet to be overcome. In this work, we develop a well-controlled SiO 2 encapsulation approach to stabilize Cu-based CO 2 R electrocatalysts against reconstruction. Using Cu nanowires (CuNWs) as a model platform, we demonstrate that SiO 2 encapsulation can significantly suppress Cu reconstruction while retaining ∼95% of the initial CO 2 R performance over 24-h stability tests at −1.15 V vs reversible hydrogen electrode ( V RHE ). In contrast, unencapsulated CuNWs exhibit severe structural deterioration with attenuated CO 2 R activity under identical testing conditions. In situ Raman studies and density functional theory (DFT) calculations reveal that the antireconstruction effect results from the formation of a robust Cu–O–Si interface that can not only serve as a structural anchor but also contribute to strengthening the Cu–Cu bonding at the exposed Cu active sites during CO 2 R operation. These results decipher the stabilizing mechanism of SiO 2 encapsulation, and provide key insights for designing durable Cu-based CO 2 R electrocatalysts toward practical applications.