Boost Selectivity of HCOO⁻ Using Anchored Bi Single Atoms towards CO₂ Reduction

Abstract

Abstract Single atoms have been widely applied as efficient catalysts in various catalytic systems due to its high selectivity for certain products, which is induced by a uniform coordinate environment of active sites. Herein, it is demonstrated that Bi single atoms anchored on carbon black (Bi SAs/C) can serve as an efficient catalyst for CO 2 electroreduction into formate (HCOO − ). During CO 2 electroreduction, Bi SAs/C achieved a faradaic efficiency for HCOO − of 83.6 % at−1.1 Vversus reversible hydrogen electrode (V vs. RHE). Notably, the selectivity for HCOO − of Bi SAs/C was always higher than 95 % at all applied potentials. In addition, at−1.2 Vvs.RHE, the current density for HCOO − formation in thepresence of Bi SAs/C reached−12.0 mA cm −2 , which was 3.4 times as high as that (−3.5 mA cm −2 ) of BiO x clusters on carbon black (BiO x /C). Mechanistic studies revealed that Bi SAs/C facilitated the faradaic process and accelerated reaction kinetics in comparison with BiO x /C.