Strong Electronic Coupling Effects at the Heterojunction Interface of SnO<sub>2</sub> Nanodots and g-C<sub>3</sub>N<sub>4</sub> for Enhanced CO<sub>2</sub> Electroreduction
Qian Zhang, Mingzi Sun, Chen‐Yue Yuan, Qiwen Sun, Bolong Huang, Hao Dong, Ya‐Wen Zhang
Abstract
Constructing abundant surface/interface structures has significant impacts on improving the performance of electrochemical CO 2 reduction reaction (CO 2 RR) catalysts. For developing high-performance CO 2 RR catalysts, herein we report a 0D/2D heterojunction structure of SnO 2 nanodots (∼2 nm) confined on graphitic carbon nitride (g-C 3 N 4 ) nanosheets for promoting the conversion of CO 2 to formate. Experimental and theoretical studies demonstrate that the abundant N-coordinating sites of g-C 3 N 4 and highly distributed SnO 2 nanodots synergistically lead to strong metal oxide–support interactions, and the substantial heterojunction interface in SnO 2 /g-C 3 N 4 has induced efficient electron transfer from electron-rich g-C 3 N 4 to SnO 2 mainly through p–p orbital couplings. As a result, the SnO 2 /g-C 3 N 4 heterojunction provides superior activity and stability for the conversion of CO 2 RR to formate, with a Faradic efficiency of 91.7% at −0.88 V vs RHE. Moreover, the proposed 0D/2D heterojunction strategy was extended to In 2 O 3 /g-C 3 N 4, supplying a universal strategy to achieve efficient hybrid catalysts for CO 2 RR in the production of high-value chemicals.