High‐Performance Electrocatalytic Carbon Dioxide Reduction to Formic Acid on Cypress‐Like Enzyme‐Antimony‐Bismuth Biohybrid

ABSTRACT Electrocatalytic carbon dioxide (CO ₂ ) reduction reaction (CO ₂ RR) to valuable liquid fuels offers a promising solution for global warming. The challenges of low CO ₂ delivery and poor product selectivity hinder the practical application of CO ₂ RR technology. This study proposes electrocatalytic CO ₂ ‐to‐formic acid (HCOOH) conversion using a cypress‐like carbonic anhydrase/antimony‐decorated bismuth (CA/Sb‐decorated Bi) biohybrid. The carbonic anhydrase (CA) as CO ₂ shuttle can enrich CO ₂ concentration on the electrode surface, accelerating the CO ₂ hydration kinetics and reaction rate. Density functional theory (DFT) calculations indicate that the introduction of Sb can alter the adsorption energy of H* and HCOO*, which is beneficial for CO ₂ RR to form HCOOH. Besides, CA/Sb‐decorated Bi biohybrid can suppress competitive hydrogen evolution reactions (HER). Consequently, the CA/Sb‐decorated Bi biohybrid achieves the Faradaic efficiency of 93.41% and 100% selectivity for HCOOH at −1.3 V. This work demonstrates the application potential of enzyme modification and metal decorating in CO ₂ RR for the development of sustainable energy.