Hybrid Metal–Boron Diatomic Site Embedded in C<sub>2</sub>N Monolayer Promotes C–C Coupling in CO<sub>2</sub> Electroreduction
Miaomiao He, Wei An, Yuanqiang Wang, Yong Men, Shuang Liu
Abstract
Abstract Double‐atom catalyst (DAC) has gained much interest for its versatile tuning and synergistic effect of dual‐atom active sites. Metal (M)–metal (M) diatomic sites, either homo‐ or heteronuclear, are typically researched. Hybrid metal‐non‐metal combined sites have rarely been studied and even the viability of such active sites are unknown. Herein, CO 2 electroreduction (CO 2 RR) is explored on M@X‐C 2 N (M = Fe, Co, Ni, and Cu; X = S, P, and B) which renders naturally generated M–X diatomic site. Using spin‐polarized density functional theory coupled with computational hydrogen electrode model, it is demonstrated that the functionality of hybrid M–B dual‐atom center is superior over that of a single‐ or double‐M center in driving CO 2 RR especially C–C coupling. Among metal–boron DACs studies, Fe@B‐C 2 N (μ = 2μ B ) exhibits the lowest free energy barrier of 0.17 eV in C–C coupling whereas Ni@B‐C 2 N (μ = 0μ B ) mainly produces CH 4 with the lowest barrier of 0.42 eV. Hence, the electronic spin state of M can be particularly important in modulating selectivity and C–C coupling barrier in CO 2 RR. Fe@B‐C 2 N is predicted as the promising catalyst for CO 2 RR towards C 2+ products owing partially to its enhanced spin state. The findings can enrich the design strategy of electrocatalysts normally running at ambient conditions.