Hydropathy modulation on Bi 2 S 3 for enhanced electrocatalytic CO 2 reduction

Electrochemical CO 2 reduction reaction (CO 2 RR) is a promising way to achieve carbon neutrality. However, the activity and selectivity of CO 2 RR are limited by not only the development of earth‐abundant catalysts but also the CO 2 mass transfer during the CO 2 RR process. Herein, Bi 2 S 3 nanorods were synthesized under a relatively mild route. Furthermore, benefitting to the modulation of the hydropathy, the optimized sample (BS‐P1) achieved a Faradaic efficiency of HCOO − (> 90%) in the range from − 0.9 to − 1.2 V, a high current density of HCOO − (2.29 times larger than that of BS‐P0 at − 1.2 V) and a prolonged stability from 12 to 20 h at − 1.1 V. When the temperature decreased from 25 to 0 °C and eventually to − 20 °C, the reaction kinetics of CO 2 RR was slowed down, the distribution of products was changed and hydrogen evolution reaction (HER) was inhibited. This work provides a facile synthesis for Bi 2 S 3 and highlights the importance of triple‐phase interfaces in CO 2 RR.