Atomic disorder boost the intrinsic activity of the electrocatalyst for electrochemical CO2 reduction

Electrochemical conversion of carbon dioxide into formic acid, which is one of the most economically viable chemicals, has been demonstrated as an efficient approach for closing the carbon cycle. However, it’s still challenging to reduce the overpotentials and increase the current densities for the future deployment of the CO 2 electrolysis technology. Here, we boost the intrinsic activity of the Bi-based electrocatalyst through the synergy of the enhanced charge transfer and mass transport process in the electrochemical reactions by generating an atomic disorder in the crystal lattices. The amorphous Bi-based quantum dots (a-BiQDs) serve as promising electrocatalysts toward formate production in a wide potential range with high Faradaic efficiency ( FE ) and energy efficiency ( EE ) in both the conventional H-cell and flow-cell, which is almost 5-fold enhanced in comparison with its crystalline counterpart. The maximum FEs of 94.44 % and 98.89 % are achieved at the potential of −1.0 V vs. RHE in the H-cell and flow-cell, respectively. Furthermore, long-term stability of more than 900 h is demonstrated in a two-electrode configuration. Combined molecular dynamics and first-principle calculations ascribe the remarkable activity toward formate production to synergistically accelerated mass transport and charge transfer kinetics during the electrocatalytic process. This work provides an effective approach for constructing electrocatalysts with high intrinsic activity, desired selectivity, and sufficient durability for large-scale deployment of CO 2 electrolysis technology.