In situ revealing C–C coupling behavior for CO <sub>2</sub> electroreduction on tensile strain Pt <sup> <i>δ</i> + </sup> –Cu <sup> <i>δ</i> + </sup> dual sites
Fengya Ma, Pu Huang, Jing Zhou, Hongwei Zeng, Jiawei Zhang, Hui Zhao, Yuming Dong, Yongfa Zhu, Yao Wang
Abstract
Abstract Engineering the desired dual metal sites to realize C–C coupling of CO 2 is of great importance for the practical applications of CO 2 electroreduction reaction (CER). Herein, an efficient strategy for constructing heterogeneous Pt δ + –Cu δ + dual sites to strengthen the generation and coupling of *CO and *CHO (or *COH) during CER process is presented in this work. The radii‐larger Pt not only stabilizes the Cu δ + but also induces a tensile strain in Pt δ + –Cu δ + dual sites. The obtained Pt δ + –Cu δ + dual sites achieve a total Faradaic efficiency and current density of C 2 products with 70.9% and 586.9 mA·cm −2 at – 1.20 V (vs. RHE), which is higher than that of Cu δ + single site (55.4%, 286.9 mA·cm −2 ). The in situ attenuated total reflection surface‐enhanced infrared absorption spectroscopy (ATR‐SEIRAS) reveals that the Pt δ + –Cu δ + dual sites can promote the generation of C 1 intermediates (such as *CO, *COOH, *COH, and *CHO) and C–C coupling. Additional in situ surface‐enhanced Raman spectra demonstrate that Pt δ + –Cu δ + dual sites can induce the generation of the high‐frequency peak for *CO atop , thus accelerating the C–C coupling. This work provides a promising avenue for stabilizing and enhancing the performance of Cu δ + sites toward CER.