In‐Situ Constructuring of Copper‐Doped Bismuth Catalyst for Highly Efficient CO₂Electrolysis to Formate in Ampere‐Level

Abstract

CO2 electrochemical reduction (CO2RR) can mitigate environmental issues while providing valuable products, yet challenging in activity, selectivity, and stability. Here, a CuS‐Bi2S3 heterojunction precursor is reported that can in situ reconstruct to Cu‐doped Bismuth (CDB) electrocatalyst during CO2RR. The CDB exhibits an industrial‐compatible current density of −1.1 A cm−2 and a record‐high formate formation rate of 21.0 mmol h−1 cm−2 at −0.86 V versus the reversible hydrogen electrode toward CO2RR to formate, dramatically outperforming currently reported catalysts. Importantly, the ultrawide potential region of 1050 mV with high formate Faradaic efficiency of over 90% and superior long‐term stability for more than 100 h at −400 mA cm−2 can also be realized. Experimental and theoretical studies reveal that the remarkable CO2RR performance of CDB results from the doping effect of Cu which optimizes adsorption of the *OCHO and boosts the structural stability of metallic bismuth catalyst. This study provides valuable inspiration for the design of element‐doping electrocatalysts to enhance catalytic activity and durability.

Structural reconstruction of BiPbO2Br nanosheets for electrochemical CO2reduction to formate

“…The electrochemical active surface area (ECSA) was determined by the following equation:in which S is the geometric area of the work electrode (1 cm 2 ), C dl is the double-layer capacitance, and C s is the specific capacitance (40 μF cm −2 ). 33,38…”

Photoelectrochemical and electrochemical CO2reduction to formate on post-transition metal block-based catalysts

“…11, the current density is concentrated in the range from −400 mA cm −2 to −50 mA cm −2 with a faradaic efficiency of formate of above 90%. 87–108 Five catalysts exhibited above FE formate of 90% at more negative current density than −400 mA cm −2 . Among them, the current density of Bi NBs and Bi 2 S 3 -derived catalysts can reach ampere class.…”

“…14c). 101,107,108 However, the stability performance was further improved in both the flow cell and MEA. And the pH value and cell structure needed to be optimized during the long-term CO 2 RR.…”

Promoting water dissociation for efficient solar driven CO2 electroreduction via improving hydroxyl adsorption

“…5b). Specially, the signal at 1364 cm −1 assigned to the O-C-O symmetric vibration of OCHO* can be observed at −0.78 V while the intensity of OCHO* increases continuously with more negative potentials applied, indicating that OCHO* is the intermediate in formate formation 65,66 . The observation of OCHO* intermediate provides a strong support for the reaction mechanism proposed in our DFT calculations.…”