Hollow penetration electrode of Bi with dislocated lattice enabling ampere-level reduction of CO2 exclusively to formate

CO2 electroreduction to valuable chemicals using renewable energy is a prospective strategy for realizing carbon neutrality, however, exclusive production of formate under high industry current densities (> 200 mA cm(-2)) remains challenging. Herein, we presented a lattice-dislocated hollow-fiber Bi via in situ reconstruction to make a breakthrough for such issue. A nearly perfect formate Faradaic efficiency of > 99.5 % was realized with a current density of 1 A cm(-2), completely suppressing CO and hydrogen generation. Finite element simulations showed high-concentration CO2 feeding was realized even though at ampere-level current density. And density functional theory calculations revealed that the abundant dislocated lattice acting as the active sites boosted the production of OCHO* . Thus, the synergistic combination of penetration and strain effects induced by the latticedislocated Bi hollow penetration electrode is responsible for such remarkable activities. This work represents a large step toward the application of direct conversion of CO2.

Automated summary

The electroreduction of CO2 to valuable chemicals using renewable energy is a promising strategy for achieving carbon neutrality, but it remains challenging under high industry current densities. In this work, a lattice-dislocated hollow-fiber Bi electrode was developed to address this issue. The electrode showed a nearly perfect formate Faradaic efficiency at a current density of 1 A cm(-2), effectively suppressing CO and hydrogen generation. The results suggest that the lattice-dislocated Bi hollow electrode, which induces penetration and strain effects, plays a crucial role in promoting CO2 conversion.