Unconventional Electrocatalytic CO Conversion to C2 Products on Single‐Atomic Pd−Agn Sites

• Published in: Angewandte Chemie International Edition Vol. 63; no. 43; pp. e202411194 - n/a
• Main Authors: Ji, Yali, Lv, Ximeng, Wei, Ruilin, Guan, Anxiang, Yang, Chao, Yan, Yaqin, Kuang, Min, Zheng, Gengfeng
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 21.10.2024
• Edition: International ed. in English
• Subjects: Adsorption; C2 products; Carbon dioxide; Carbon monoxide; Catalysts; Chemical reduction; CO binding strength; CO electroreduction; Copper; C−C coupling; Electrochemistry; Palladium; Pressure; Room temperature; Silver; single-atomic sites
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202411194

The electrochemical reduction of CO or CO2 into C2+ products has mostly been focused on Cu‐based catalysts. Although Ag has also been predicted as a possible catalyst for the CO‐to‐C2+ conversion from the thermodynamic point of view, however, due to its weak CO binding strength, CO rapidly desorbs from the Ag surface rather than participates in deep reduction. In this work, we demonstrate that single‐atomic Pd sites doped in Ag lattice can tune the CO adsorption behavior and promote the deep reduction of CO toward C2 products. The monodispersed Pd−Agn sites enable the CO adsorption with both Pd‐atop (PdL) and Pd−Ag bridge (PdAgB) configurations, which can increase the CO coverage and reduce the C−C coupling energy barrier. Under room temperature and ambient pressure, the Pd1Ag10 alloy catalyst exhibited a total CO‐to‐C2 Faradaic efficiency of ~37 % at −0.83 V, with appreciable current densities and electrochemical stability, thus featuring unconventional non‐Cu electrocatalytic CO‐to‐C2 conversion capability. Compared to the non‐*CO adsorption on Ag surface or over‐strong *CO adsorption on multiple Pd atoms, the single Pd atoms surrounded with multiple Ag sites (denoted as the Pd−Agn structure) in the Pd1Ag10 catalyst allow to tune the *CO adsorption behavior to promote the *CO surface coverage, and enable efficient C−C coupling between a Pd‐atop (PdL) and a Pd−Ag bridge (PdAgB) adsorption sites.