Bismuth-based materials(e.g., metallic, oxides and subcarbonate) are emerged as promising electrocatalysts for converting CO_(2) to formate. However, Bio-based electrocatalysts possess high overpotentials, while bismu...Bismuth-based materials(e.g., metallic, oxides and subcarbonate) are emerged as promising electrocatalysts for converting CO_(2) to formate. However, Bio-based electrocatalysts possess high overpotentials, while bismuth oxides and subcarbonate encounter stability issues. This work is designated to exemplify that the operando synthesis can be an effective means to enhance the stability of electrocatalysts under operando CO_(2)RR conditions. A synthetic approach is developed to electrochemically convert Bi^(O)Cl into Cl-containing subcarbonate(Bi_(2)O_(2)(CO_(3))_(x)Cl_(y)) under operando CO_(2)RR conditions. The systematic operando spectroscopic studies depict that BiOCl is converted to Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) via a cathodic potential-promoted anion-exchange process. The operando synthesizedBi_(2)O_(2)(CO_(3))_(x)Cl_(y) can tolerate-1.0 V versus RHE, while for the wet-chemistry synthesized pure Bi_(2)O_(2)CO_(3),the formation of metallic Bio occurs at-0.6 V versus RHE. At-0.8 V versus RHE, Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) can readily attain a FEHCOO-of 97.9%,much higher than that of the pure Bi_(2)O_(2)CO_(3)(81.3%). DFT calculations indicate that differing from the pure Bi_(2)O_(2)CO_(3)-catalyzed CO_(2)RR, where formate is formed via a *OCHO intermediate step that requires a high energy input energy of 2.69 eV to proceed, the formation of H COO-over Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) has proceeded via a *COOH intermediate step that only requires low energy input of 2.56 eV.展开更多
基金financially supported by Australian Research Council Discovery Project(DP200100965)。
文摘Bismuth-based materials(e.g., metallic, oxides and subcarbonate) are emerged as promising electrocatalysts for converting CO_(2) to formate. However, Bio-based electrocatalysts possess high overpotentials, while bismuth oxides and subcarbonate encounter stability issues. This work is designated to exemplify that the operando synthesis can be an effective means to enhance the stability of electrocatalysts under operando CO_(2)RR conditions. A synthetic approach is developed to electrochemically convert Bi^(O)Cl into Cl-containing subcarbonate(Bi_(2)O_(2)(CO_(3))_(x)Cl_(y)) under operando CO_(2)RR conditions. The systematic operando spectroscopic studies depict that BiOCl is converted to Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) via a cathodic potential-promoted anion-exchange process. The operando synthesizedBi_(2)O_(2)(CO_(3))_(x)Cl_(y) can tolerate-1.0 V versus RHE, while for the wet-chemistry synthesized pure Bi_(2)O_(2)CO_(3),the formation of metallic Bio occurs at-0.6 V versus RHE. At-0.8 V versus RHE, Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) can readily attain a FEHCOO-of 97.9%,much higher than that of the pure Bi_(2)O_(2)CO_(3)(81.3%). DFT calculations indicate that differing from the pure Bi_(2)O_(2)CO_(3)-catalyzed CO_(2)RR, where formate is formed via a *OCHO intermediate step that requires a high energy input energy of 2.69 eV to proceed, the formation of H COO-over Bi_(2)O_(2)(CO_(3))_(x)Cl_(y) has proceeded via a *COOH intermediate step that only requires low energy input of 2.56 eV.
