Enhanced CO₂ Electrochemical Reduction Performance over Cu@AuCu Catalysts at High Noble Metal Utilization Efficiency

Abstract

The electrochemical CO 2 reduction reaction (CO 2 RR) represents a viable alternative to help close the anthropogenic carbon cycle and convert intermittent electricity from renewable energy sources to chemical energy in the form of value-added chemicals. The development of economic catalysts possessing high faradaic efficiency (FE) and mass activity (MA) toward CO 2 RR is critical in accelerating CO 2 utilization technology. Herein, an elaborate Au−Cu catalyst where an alloyed AuCu shell caps on a Cu core (Cu@AuCu) is developed and evaluated for CO 2 -to-CO electrochemical conversion. Specific roles of Cu and Au for CO 2 RR are revealed in the alloyed core−shell structure, respectively, and a compositional-dependent volcano-plot is disclosed for the Cu@AuCu catalysts toward selective CO production. As a result, the Au 2 −Cu 8 alloyed core−shell catalyst (only 17% Au content) achieves an FE CO value as high as 94% and an MA CO of 439 mA/mg Au at −0.8 V (vs RHE), superior to the values for pure Au, reflecting its high noble metal utilization efficiency.

CO-tolerant RuNi/TiO2 catalyst for the storage and purification of crude hydrogen

“…= 1.2) than Ru–Ru scattering (C.N. = 4.4) demonstrates the Ru atoms still form small clusters instead of dissolving in Ni matrix 33 . This evidence indicates Ru and Ni species are in separated phases with strong interactions rather than a solid-solution alloy 34 .…”

Highly‐Efficient CO2 Electromethanation with Extremely Low Overpotentials on Pt/C Catalysts: Strategic Design of Multi‐Potential‐Step Method

“…Electrocatalysts, such as Au, Ag, Cu, etc., are well known as popular choices for experimental designs due to their CO 2 reduction activity, [3–27] although, these metals require high overpotentials. The overpotentials of $${\ge }$$ 0.3 V, $${\ge }$$ 0.6 V, and $${\ge }$$ 0.9 V are required for Au, Ag, and Cu electrocatalysts, respectively [28] .…”

Theoretical Investigation of Cu–Au Alloy for Carbon Dioxide Electroreduction: Cu/Au Ratio Determining C1/C2 Selectivity

“…In the electroreduction of CO 2 , Cu exhibits special properties, and it is the only metal that can electrically reduce CO 2 to C 2+ products currently. − However, as experimental studies have shown that CO 2 ER on Cu will generate H 2 and various C 1 , C 2 , and C 3 products, the product selectivity of Cu catalysts is still an urgent problem to be solved. − Accordingly, many modulation strategies have been applied in Cu-based catalysts to improve their electrocatalytic performance. A typical one is a bimetallic strategy, and there have been quite a few experimental results to prove the effectiveness of this scheme, such as Zn, − Ag, , and Au, − whose introduction into Cu will enhance the selectivity of C 2 oxygenates in the CO 2 ER. Among them, the CuAu alloy that changes the C 1 /C 2 product ratio with the change of the element composition ratio has attracted our attention. − The pioneering report of CuAu alloy for CO 2 ER comes from Jia and co-workers, and their report demonstrated that Cu 36.9 Au 36.1 /NCF shows high Faraday efficiency (∼28%) for the production of C 2 H 5 OH.…”