Decorating graphdiyne on ultrathin bismuth subcarbonate nanosheets to promote CO2 electroreduction to formate

This outstanding CO 2 electroreduction performance is attributed to the electron-rich nature of GDY decorated on the surface of BOC, which greatly elevates the adsorption capacity of CO 2 , the amount of metallic bismuth sites and the rate of charge transfer. Electrocatalytic reduction of CO 2 is one of the most attractive approaches for converting CO 2 into valuable chemical feedstocks and fuels. This work reports a catalyst comprising graphdiyne-decorated bismuth subcarbonate (denoted as BOC@GDY) for efficient electroreduction of CO 2 to formate. The BOC@GDY shows a stable current density of 200 mA cm −2 at –1.1 V in a flow cell configuration, with a faradaic efficiency of 93.5% for formate. Experimental results show that the synergistic effect in BOC@GDY is beneficial for the CO 2 adsorption affinity, the reaction kinetics and the selectivity for formate. In addition, in-situ X-ray absorption and Raman spectroscopy indicate that the electron-rich GDY could facilitate the reduction from Bi(III) to Bi(0), thus leading to more active sites. We also demonstrate that the promoting effect of GDY in CO 2 electroreduction can be further extended to other metal catalysts. To the best of our knowledge, such general promoting functions of GDY for CO 2 electroreduction have not been documented thus far.