Synergistic Cr<sub>2</sub>O<sub>3</sub>@Ag Heterostructure Enhanced Electrocatalytic CO<sub>2</sub> Reduction to CO
Huai Qin Fu, Junxian Liu, Nicholas Bedford, Yun Wang, Ji Wei Sun, Yu Zou, Mengyang Dong, Joshua Wright, Hui Diao, Porun Liu, Hua Gui Yang, Huijun Zhao
Abstract
Abstract The electrocatalytic CO 2 RR to produce value‐added chemicals and fuels has been recognized as a promising means to reduce the reliance on fossil resources; it is, however, hindered due to the lack of high‐performance electrocatalysts. The effectiveness of sculpturing metal/metal oxides (MMO) heterostructures to enhance electrocatalytic performance toward CO 2 RR has been well documented, nonetheless, the precise synergistic mechanism of MMO remains elusive. Herein, an in operando electrochemically synthesized Cr 2 O 3 –Ag heterostructure electrocatalyst (Cr 2 O 3 @Ag) is reported for efficient electrocatalytic reduction of CO 2 to CO. The obtained Cr 2 O 3 @Ag can readily achieve a superb FE CO of 99.6% at −0.8 V (vs RHE) with a high J CO of 19.0 mA cm −2 . These studies also confirm that the operando synthesized Cr 2 O 3 @Ag possesses high operational stability. Notably, operando Raman spectroscopy studies reveal that the markedly enhanced performance is attributable to the synergistic Cr 2 O 3 –Ag heterostructure induced stabilization of CO 2 •− /*COOH intermediates. DFT calculations unveil that the metallic‐Ag‐catalyzed CO 2 reduction to CO requires a 1.45 eV energy input to proceed, which is 0.93 eV higher than that of the MMO‐structured Cr 2 O 3 @Ag. The exemplified approaches in this work would be adoptable for design and development of high‐performance electrocatalysts for other important reactions.