Rational design of low loading Pd-alloyed Ag nanocorals for high current density CO2-to-CO electroreduction at elevated pressure. (March 2022)

• Record Type: Journal Article
• Authors: Mahyoub, Samah A.; Qaraah, Fahim A.; Yan, Shenglin; Hezam, Abdo; Zhong, Juhua; Cheng, Zhenmin
• Is Part Of: Materials today energy. Volume 24(2022)
• Publication Date: 2022-03
• Subjects: Ag–Pd Nano coral -- High pressure -- CO2 electroreduction -- Low overpotential; Energy development -- Periodicals; Energy industries -- Periodicals; Power resources -- Periodicals; Energy policy -- Periodicals; Energy development; Energy industries; Energy policy; Power resources; Electronic journals; Periodicals; 621.042
• DOI: 10.1016/j.mtener.2021.100923
• Languages: English
• ISSNs: 2468-6069

Abstract

Abstract: Adjusting a bimetallic electrocatalyst's geometric and electronic structure to promote a certain reaction pathway and provide more active sites is a viable approach for improving the activity and selectivity of an electrocatalytic CO2 reduction process. Here, the authors, for the first-time design, self-supported 3D Ag–Pd nano-coral electrodes with a low loading Pd content through a simple and scalable approach using hydrogen bubble dynamic templates. At −0.6 V vs. Reversible hydrogen evaluation (RHE) CO2, the Ag96.1 Pd3.9 bimetallic electrode converts CO2 to CO with a promoted faradic efficiency of 91.5% and partial current density (18.13 mA cm −2 ). This upgraded activity can be attributed to the aspects that the addition of Pd supports the vital intermediate generation with coral morphology, offers numerous active sites and rises CO2 concentration. In addition, because the catalyst is self-supported, there is no overpotential at the catalyst/support interface. Finally, CO achieved a partial current density of −318 mA cm −2 by rising CO2 pressure to as elevated as 9.5 bar to raise CO2 content. To the best of our knowledge, these findings establish a high record in neutral pH electrolytes for most Ag-based electrodes. Graphical abstract: Image 1 Highlights: The self-supported 3D Ag–Pd Nano-Coral electrodes are prepared through the hydrogen bubble dynamic templates. Small amounts of Pd benefit the activity of Ag96.1 Pd3.9 toward CO2 electroreduction reaction. Hierarchically corals structure of Ag96.1 Pd3.9 offers numerous active sites and rises CO2 concentration. Increasing CO2 partial pressure is useful for CO2 electroreduction reaction.