High Performance 3D Self-Supporting Cu-Bi Aerogels for Electrocatalytic Reduction of CO₂ to Formate

The electrocatalytic reduction of CO₂ (CO₂ RR) to CO, formate, methane, and other high-value compounds is a promising technique. However, current electrocatalysts suffer from drawbacks such as few active catalytic sites, poor selectivity and low stability, etc, which restrict the practical application. Although monatomic metal catalysts have been widely reported in recent years, high performance non-noble metal aerogels were rarely investigated for electrocatalytic CO₂ RR. Herein, Cu-Bi aerogels with boosted CO₂ RR activity were well constructed by a simple one-step self-assembly method. The resultant Cu₁ Bi₂ exhibits excellent CO₂ RR activity with high faradaic efficiency (FE) of 96.57 % towards HCOOH at a potential of -0.9 V vs. RHE, and the FE_HCOOH remains over 80.18 % in a wide potential window (-0.8 V to -1.2 V vs. RHE). It demonstrated that the enhanced CO₂ RR activity of Cu-Bi aerogels could be attributed to the 3D self-supporting structure of the catalysis, synergistic effect, and low interfacial charge transfer resistance.