Lithiation‐Enabled High‐Density Nitrogen Vacancies Electrocatalyze CO2 to C2 Products
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2021-08-20 |
| Journal | Advanced Materials |
| Authors | Peng Chen, Gan Luo, Zikai Xu, Shuai Yan, Junbo Zhang |
| Institutions | Shangqiu Normal University, Fudan University |
| Citations | 89 |
Abstract
Section titled “Abstract”Abstract Electrochemical CO 2 reduction to produce valuable C 2 products is attractive but still suffers with relatively poor selectivity and stability at high current densities, mainly due to the low efficiency in the coupling of two CO intermediates. Herein, it is demonstrated that high‐density nitrogen vacancies formed on cubic copper nitrite (Cu 3 N x ) feature as efficient electrocatalytic centers for CO-CO coupling to form the key OCCO intermediate toward C 2 products. Cu 3 N x with different nitrogen densities are fabricated by an electrochemical lithium tuning strategy, and density functional theory calculations indicate that the adsorption energies of CO* and the energy barriers of forming key C 2 intermediates are strongly correlated with nitrogen vacancy density. The Cu 3 N x catalyst with abundant nitrogen vacancies presents one of the highest Faradaic efficiencies toward C 2 products of 81.7 ± 2.3% at −1.15 V versus reversible hydrogen electrode (without ohmic correction), corresponding to the partial current density for C 2 production as −307 ± 9 mA cm −2 . An outstanding electrochemical stability is also demonstrated at high current densities, substantially exceeding CuO x catalysts with oxygen vacancies. The work suggests an attractive approach to create stable anion vacancies as catalytic centers toward multicarbon products in electrochemical CO 2 reduction.