Benzotriazole and Poly(vinylidene Fluoride) Synergistically Promote the Selectivity of Carbon Dioxide Reduction on Copper toward C<sub>2</sub> Products
Chengcheng Zhu, Zhongyan Gong, Xinya Chen, Lu Jiang, Haonan Chen, Furong Qiao, Qinghua Liu, Yaning Liu, Gang Lü
Abstract
Electrochemical reduction of carbon dioxide (CO 2 RR) to valuable chemicals offers a promising solution to mitigate CO 2 emissions and address the energy crisis. Surface modification of the catalyst surface with small molecules or polymers could modulate the product selectivity of the CO 2 RR. If a properly chosen polymer and molecule were combined together, a significant improvement in the CO 2 RR might be realized. Herein, we demonstrate that sequential coating of Cu catalyst with benzotriazole (BTA) and poly(vinylidene fluoride) (PVDF) significantly enhances the product selectivity toward C 2 species. The Faradaic efficiency (FE) of C 2 hydrocarbons increased from 49 to 70% at −1.05 V vs the reversible hydrogen electrode (RHE) in an H-type electrochemical cell, with stable performance maintained over 10 h. The coated BTA molecules could enhance the CO 2 RR activity and promote the production of C 2 species, while the PVDF layer prevents the BTA molecules from dissolving/detaching and regulates the surface coverage of *CO and *H intermediates. This dual-layer modification strategy provides a simple and effective approach to improve the Faradaic efficiencies (FEs) of the CO 2 RR on Cu. Furthermore, this strategy may be integrated with other strategies to further optimize the CO 2 RR performance, offering a versatile pathway for advancing sustainable energy conversion technologies.