Mastering the Lattice Strain in Bismuth‐Based Electrocatalysts for Efficient CO₂‐to‐Formate Conversion

Abstract Tuning the lattice strain of catalysts represents a powerful strategy to alter their electronic structures and ultimately regulate catalytic performance. Electrocatalytic CO₂ reduction is a promising avenue to accomplish the carbon‐neutral cycle, however, there still lacks a distinct and systematic understanding of the lattice strain effect in CO₂ electrochemical conversion. In this work, the influence of lattice strain on Bi (012) facets to formate production is studied. The pre‐executed density functional theory (DFT) calculations reveal that lattice compression promotes the wrinkling of exposed Bi surface and increases the total density of state (DOS) of active sites at the Fermi level. As the gradual intensification of lattice contraction, the selectivity of CO₂ reduction exhibits a volcanic alteration, with an optimal lattice contraction of 3%. Experimentally synthesized Bi₂O₂CO₃/Bi heterogeneous catalyst confirms the effect of lattice compression. When compression reaches −3.04% on Bi (012) facets, the catalyst possesses the highest Faraday efficiency (FE) of 96.17% at −1.2 V_RHE and an industrially scalable current density of −600 mA cm⁻². Additionally, in seawater‐based electrolysis, the catalyst also exhibits excellent remarkable FE of 95.43% of formate production.