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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]

The electrochemical CO2 reduction reaction (eCO2RR) to multicarbon products has been widely recognized for Cu‐based catalysts. However, the structural changes in Cu‐based catalysts during the eCO2RR pose challenges to achieving an in‐depth understanding of the structure–activity relationship, thereby limiting catalyst development. Herein, we employ constant‐potential density functional theory calculations to investigate the sintering process of Cu single atoms of Cu−N−C single‐atom catalysts into clusters under eCO2RR conditions. Systematic constant‐potential ab initio molecular dynamics simulations revealed that the leaching of Cu−(CO)x moieties and subsequent agglomeration into clusters can be facilitated by synergistic adsorption of H and eCO2RR intermediates (e.g. CO). Increasing the Cu2+ concentration or the applied potential can efficiently suppress Cu sintering. Both microkinetic simulations and experimental results further confirm that sintered Cu clusters play a crucial role in generating C2 products. These findings provide significant insights into the dynamic evolution of Cu‐based catalysts and the origin of their activity toward C2 products during the eCO2RR. [ABSTRACT FROM AUTHOR]

Lithium (Li)‐metal batteries are promising next‐generation energy storage systems. One drawback of uncontrollable electrolyte degradation is the ability to form a fragile and nonuniform solid electrolyte interface (SEI). In this study, we propose the use of a fluorinated carbon nanotube (CNT) macrofilm (CMF) on Li metal as a hybrid anode, which can regulate the redox state at the anode/electrolyte interface. Due to the favorable reaction energy between the plated Li and fluorinated CNTs, the metal can be fluorinated directly to a LiF‐rich SEI during the charging process, leading to a high Young's modulus (~2.0 GPa) and fast ionic transfer (~2.59×10−7 S cm−1). The obtained SEI can guide the homogeneous plating/stripping of Li during electrochemical processes while suppressing dendrite growth. In particular, the hybrid of endowed full cells with substantially enhanced cyclability allows for high capacity retention (~99.3 %) and remarkable rate capacity. This work can extend fluorination technology into a platform to control artificial SEI formation in Li‐metal batteries, increasing the stability and long‐term performance of the resulting material. [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]

Plasmonic photo-electrocatalytic CO2 conversion is an effective approach for converting CO2 into valuable chemicals than traditional photo and electrocatalysis. Advanced photo catalysts offer the unique benefits of harvesting visible light while regulating the catalytic properties via optimized size, morphology, or composition. In this regard, exploring photoelectric synergistic catalysis with high activity and selectivity is critical. In addition to photoelectrochemical properties, suppressing side reactions such as hydrogen evolution reaction is the main bottleneck in exploring CO2 reduction on the plasmonic photoelectrode for enhanced selectivity. This review focuses on plasmonic materials toward photoelectrochemical CO2 reaction, which provides a new strategy for CO2 conversion via synergy between visible light and electrocatalysis. The spatial visible light absorption of plasmonic nanomaterials for CO2 conversion in various sizes and shapes and composites with other metals or semiconductors is highlighted in detail. Additionally, operando/in situ spectroscopy analysis could identify intermediate species during photo-electrocatalytic CO2 reduction on the photoelectrode to comprehend the reaction mechanism and design more efficient plasmonic catalysts. We anticipate that this work will provide insights into understanding the mechanism of plasmonic photo-electrocatalytic CO2 conversion and fabrication of advanced catalysts. [ABSTRACT FROM AUTHOR]

Oxygen electrocatalysis is of great significance in electrochemical energy conversion and storage. Many strategies have been adopted for developing advanced oxygen electrocatalysts to promote these technologies. In this invited contribution, recent progress in understanding the oxygen electrochemistry from theoretical and experimental aspects is summarized. The major categories of oxygen electrocatalysts, namely, noble‐metal‐based compounds, transition‐metal‐based composites, and nanocarbons, are successively discussed for oxygen reduction and evolution. Design strategies of various oxygen electrocatalysts and their relationship on the structure–activity–performance are comprehensively addressed with the perspectives. Finally, the challenge and outlook for advanced oxygen electrocatalysts are discussed toward energy conversion and storage technologies. [ABSTRACT FROM AUTHOR]

Alkaline electrolysis plays a crucial role in sustainable energy solutions by utilizing electrolytic cells to produce hydrogen gas, providing a clean and efficient method for energy storage and conversion. Efficient, stable, and low-cost electrocatalysts for the oxygen evolution reaction (OER) are essential to facilitate alkaline water electrolysis on a commercial scale. Nickel-iron-based (NiFe-based) transition metal electrocatalysts are considered the most promising non-precious metal catalysts for alkaline OER due to their low cost, abundance, and tunable catalytic properties. Nevertheless, the majority of existing NiFe-based catalysts suffer from limited activity and poor stability, posing a significant challenge in meeting industrial applications. This also highlights a common situation where the emphasis on material activity receives significant attention, while the equally critical stability aspect is often underemphasized. Initiating with a comprehensive exploration of the stability of NiFe-based OER materials, this article first summarizes the debate surrounding the determination of active sites in NiFe-based OER electrocatalysts. Subsequently, the degradation mechanisms of recently reported NiFe-based electrocatalysts are outlined, encompassing assessments of both chemical and mechanical endurance, along with essential approaches for enhancing their stability. Finally, suggestions are put forth regarding the essential considerations for the design of NiFe-based OER electrocatalysts, with a focus on heightened stability., (© 2024 Wiley‐VCH GmbH.)

The electrochemical reduction reaction of carbon dioxide (CO 2 RR) into valuable products offers notable economic benefits and contributes to environmental sustainability. However, precisely controlling the reaction pathways and selectively converting key intermediates pose considerable challenges. In this study, our theoretical calculations reveal that the active sites with different states of copper atoms (1-3-5-7-9) play a pivotal role in the adsorption behavior of the *CHO critical intermediate. This behavior dictates the subsequent hydrogenation and coupling steps, ultimately influencing the formation of the desired products. Consequently, we designed two model electrocatalysts comprising Cu single atoms and particles supported on CeO 2 . This design enables controlled *CHO intermediate transformation through either hydrogenation with *H or coupling with *CO, leading to a highly selective CO 2 RR. Notably, our selective control strategy tunes the Faradaic efficiency from 61.1% for ethylene (C 2 H 4 ) to 61.2% for methane (CH 4 ). Additionally, the catalyst demonstrated a high current density and remarkable stability, exceeding 500 h of operation. This work not only provides efficient catalysts for selective CO 2 RR but also offers valuable insights into tailoring surface chemistry and designing catalysts for precise control over catalytic processes to achieve targeted product generation in CO 2 RR technology.

The electrochemical CO 2 reduction reaction (eCO 2 RR) to multicarbon products has been widely recognized for Cu-based catalysts. However, the structural changes in Cu-based catalysts during the eCO 2 RR pose challenges to achieving an in-depth understanding of the structure-activity relationship, thereby limiting catalyst development. Herein, we employ constant-potential density functional theory calculations to investigate the sintering process of Cu single atoms of Cu-N-C single-atom catalysts into clusters under eCO 2 RR conditions. Systematic constant-potential ab initio molecular dynamics simulations revealed that the leaching of Cu-(CO) x moieties and subsequent agglomeration into clusters can be facilitated by synergistic adsorption of H and eCO 2 RR intermediates (e.g., CO). Increasing the Cu 2+ concentration or the applied potential can efficiently suppress Cu sintering. Both microkinetic simulations and experimental results further confirm that sintered Cu clusters play a crucial role in generating C 2 products. These findings provide significant insights into the dynamic evolution of Cu-based catalysts and the origin of their activity toward C 2 products during the eCO 2 RR., (© 2024 Wiley-VCH GmbH.)

The high-current-density Zn-air battery shows big prospects in next-generation energy technologies, while sluggish O 2 reaction and diffusion kinetics barricade the applications. Herein, the sequential assembly is innovatively demonstrated for hierarchically mesoporous molybdenum carbides/carbon microspheres with a tunable thickness of mesoporous carbon layers (Meso-Mo 2 C/C-x, where x represents the thickness). The optimum Meso-Mo 2 C/C-14 composites (≈2 µm in diameter) are composed of mesoporous nanosheets (≈38 nm in thickness), which possess bilateral mesoporous carbon layers (≈14 nm in thickness), inner Mo 2 C/C layers (≈8 nm in thickness) with orthorhombic Mo 2 C nanoparticles (≈2 nm in diameter), a high surface area of ≈426 m 2  g -1 , and open mesopores (≈6.9 nm in size). Experiments and calculations corroborate the hierarchically mesoporous Mo 2 C/C can enhance hydrophilicity for supplying sufficient O 2 , accelerate oxygen reduction kinetics by highly-active Mo 2 C and N-doped carbon sites, and facilitate O 2 diffusion kinetics over hierarchically mesopores. Therefore, Meso-Mo 2 C/C-14 outputs a high half-wave potential (0.88 V vs RHE) with a low Tafel slope (51 mV dec -1 ) for oxygen reduction. More significantly, the Zn-air battery delivers an ultrahigh power density (272 mW cm -2 ), and an unprecedented 100 h stability at a high-current-density condition (100 mA cm -2 ), which is one of the best performances., (© 2023 Wiley‐VCH GmbH.)

Lithium (Li)-metal batteries are promising next-generation energy storage systems. One drawback of uncontrollable electrolyte degradation is the ability to form a fragile and nonuniform solid electrolyte interface (SEI). In this study, we propose the use of a fluorinated carbon nanotube (CNT) macrofilm (CMF) on Li metal as a hybrid anode, which can regulate the redox state at the anode/electrolyte interface. Due to the favorable reaction energy between the plated Li and fluorinated CNTs, the metal can be fluorinated directly to a LiF-rich SEI during the charging process, leading to a high Young's modulus (~2.0 GPa) and fast ionic transfer (~2.59×10 -7  S cm -1 ). The obtained SEI can guide the homogeneous plating/stripping of Li during electrochemical processes while suppressing dendrite growth. In particular, the hybrid of endowed full cells with substantially enhanced cyclability allows for high capacity retention (~99.3 %) and remarkable rate capacity. This work can extend fluorination technology into a platform to control artificial SEI formation in Li-metal batteries, increasing the stability and long-term performance of the resulting material., (© 2024 Wiley-VCH GmbH.)