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The inefficiency of Pt and Pd benchmark catalysts in achieving complete ethanol oxidation, coupled with their inherent susceptibility to poisoning, poses a significant obstacle to the advancement of direct ethanol fuel cells. In this study, the development of self‐supported and ultrathin RhCuBi trimetallenes, demonstrating exceptional performance in ethanol electrooxidation through segregation and interface engineering is presented. The distinctive RhBi‐rich crystalline/RhCu‐rich amorphous heterostructure of RhCuBi trimetallenes creates a wealth of highly active interfacial sites for the ethanol oxidation reaction (EOR). This results in an impressive 43.3% Faradaic efficiency for the C1 pathway and a peak mass activity of 1.11 A mgRh−1 at 0.68 V versus reversible hydrogen electrode. Moreover, RhCuBi trimetallenes retain 60% of their initial mass activity after 8.5 h of constant potential electrolysis, outperforming commercial Pd and Pt catalysts (<3%). In/ex situ infrared spectroscopy directly reveals the generated C1 products and the key CH3CO* intermediates for EOR on RhCuBi trimetallenes. Theoretical calculations confirm that the RhBi alloy, particularly the lattice‐stretched crystalline/amorphous interfacial sites, facilitates the adsorption/activation of ethanol and the dehydrogenation of CH3CO* toward the C1 pathway of EOR. This breakthrough offers promising prospects for enhancing the efficiency and stability of ethanol electrooxidation in fuel cell applications. [ABSTRACT FROM AUTHOR]

Revealing the dynamic reconstruction process and tailoring advanced copper (Cu) catalysts is of paramount significance for promoting the conversion of CO2 into ethylene (C2H4), paving the way for carbon neutralization and facilitating renewable energy storage. In this study, we initially employed density functional theory (DFT) and molecular dynamics (MD) simulations to elucidate the restructuring behavior of a catalyst under electrochemical conditions and delineated its restructuring patterns. Leveraging insights into this restructuring behavior, we devised an efficient, low‐coordination copper‐based catalyst. The resulting synthesized catalyst demonstrated an impressive Faradaic efficiency (FE) exceeding 70 % for ethylene generation at a current density of 800 mA cm−2. Furthermore, it showed robust stability, maintaining consistent performance for 230 hours at a cell voltage of 3.5 V in a full‐cell system. Our research not only deepens the understanding of the active sites involved in designing efficient carbon dioxide reduction reaction (CO2RR) catalysts but also advances CO2 electrolysis technologies for industrial application. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is an essential chemical for agricultural production and a promising next‐generation hydrogen‐rich fuel. The electrocatalytic nitrate (NO3−) reduction reaction (NO3RR) to NH3 provides a sustainable and low‐energy method to replace industrial NH3 synthesis. However, the NO3− to NH3 conversion is limited by the complex eight‐electron and nine‐proton reduction processes, thus it is highly desirable to develop efficient electrocatalytic materials to overcome the kinetic barrier of NO3RR. Herein, Au nanocrystals (Au‐NCs) modified holey PtTeAu metallene (PtTeAu‐ML) heteronanostructures (Au‐NCs/PtTeAu‐MLs) are designed through phase and interface engineering, which achieve the high NH3 yield (3.499 mg h−1 mgcat−1) and Faradaic efficiency of 96.3% for NO3RR at −0.03 V versus RHE. Detailed investigations reveal that the introduction of Te atoms significantly inhibits the high activity of Pt atoms for hydrogen evolution reaction that competes with NO3RR. Density functional theory results demonstrate that Au atoms further modulate the electronic structure of Pt in PtTe‐MLs, resulting in the upward shifted d band center of Pt and in turn the optimized NO3RR process on PtTeAu‐MLs. Furthermore, Au‐NCs allows the sustainable sunlight energy to accelerate the NO3RR kinetics at PtTeAu‐MLs because of the localized surface plasmon resonance of Au, inducing a higher NH3 yield of 4.684 mg h−1 mgcat−1 under light irradiation condition. [ABSTRACT FROM AUTHOR]

Electrolysis that reduces carbon dioxide (CO2) to useful chemicals can, in principle, contribute to a more sustainable and carbon-neutral future1–6. However, it remains challenging to develop this into a robust process because efficient conversion typically requires alkaline conditions in which CO2 precipitates as carbonate, and this limits carbon utilization and the stability of the system7–12. Strategies such as physical washing, pulsed operation and the use of dipolar membranes can partially alleviate these problems but do not fully resolve them11,13–15. CO2 electrolysis in acid electrolyte, where carbonate does not form, has therefore been explored as an ultimately more workable solution16–18. Herein we develop a proton-exchange membrane system that reduces CO2 to formic acid at a catalyst that is derived from waste lead–acid batteries and in which a lattice carbon activation mechanism contributes. When coupling CO2 reduction with hydrogen oxidation, formic acid is produced with over 93% Faradaic efficiency. The system is compatible with start-up/shut-down processes, achieves nearly 91% single-pass conversion efficiency for CO2 at a current density of 600 mA cm−2 and cell voltage of 2.2 V and is shown to operate continuously for more than 5,200 h. We expect that this exceptional performance, enabled by the use of a robust and efficient catalyst, stable three-phase interface and durable membrane, will help advance the development of carbon-neutral technologies.We develop a proton-exchange membrane system that reduces CO2 to formic acid at a catalyst that is derived from waste lead–acid batteries and in which a lattice carbon activation mechanism contributes. [ABSTRACT FROM AUTHOR]

Molecular oxygen can be electrochemically reduced to water via the 4e− transfer pathway or hydrogen peroxide via a 2e− pathway, which holds significant relevance within energy conversion and chemical synthesis. The specific oxygen reduction reaction (ORR) pathways intricately hinge upon the adsorption configuration and state of oxygen species. Precisely steering the adsorption state of oxygen species at the active sites serves as a crucial guiding principle for the design and preparation of ORR catalysts. This review succinctly summarizes the strategies employed to regulate the adsorption state of oxygen species on nonnoble metal catalyst surfaces, encompassing insights into the adsorption mechanism and state regulation of oxygen intermediates, with a particular focus on the 2e− ORR pathway to produce H2O2. Moreover, the persistent challenges that remain in the realm of non‐noble metal oxygen catalysts are pointed out and the prospects for their future development are meticulously evaluated. [ABSTRACT FROM AUTHOR]