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Electrocatalytic nitrate reduction reaction (NO3RR) driven by renewable energy is a promising technology for the removal of nitrate‐containing wastewater. However, the sluggish kinetics resulted from the complex proton‐coupled electron transfer and various intermediates remain the key barriers for large‐scale application of NO3RR. Herein, a tactic is reported to raise rate of NO3RR and increase selectivity to N2 using bimetal catalyst: Co is inclined to act on the key steps needed in NO3RR process, rate‐determining step (RDS: *NO3 to *NO2, the asterisk means intermediates) and the subsequent *N hydrogenation as well as Fe exhibits the efficient activity for the selectivity‐ determining step (SDS: *NO to *N then to N2) via a relay catalysis mechanism. A removal efficiency of 78.5% and an ultra‐long cycle stability of 60 cycles (12 h per cycle) are achieved on FeCo alloy confined with nitrogen‐doped porous carbon nanofibers (FeCo‐NPCNFs). DFT calculations unveil that the introduction of Co active site not only regulates the d‐band center of FeCo alloy, optimizes the adsorption of intermediates, but also has a strong capacity to supply active hydrogen species. Clearly, this study elucidates the effects of bimetallic relay catalysis on the performance of electrocatalytic NO3RR and offers avenues for designing Fe‐based catalysts to realize the nitrogen‐neutral cycle. [ABSTRACT FROM AUTHOR]

As industries and consumption patterns evolve, new electrical appliances are increasingly playing critical roles in national production, defense, and cognitive exploration. However, the slow development of energy storage devices with ultra-high energy density (beyond 500 W h kg−1) has impeded the promotion and widespread application of the next generation of intelligent, multi-scenario electrical equipment. Among the numerous ultra-high specific energy battery systems, lithium metal batteries (LMBs) hold significant potential for applications in advanced and sophisticated fields. This potential is primarily due to lithium metal's high specific capacity (3860 mA h g−1). However, LMBs face numerous challenges, including the growth of lithium dendrites, poor cycle stability, and safety concerns. In recent years, research on the mechanisms of Li metal-based battery systems, innovation in electrode materials, and optimization of device configurations have made significant progress. In this highlight, we provide a comprehensive overview of the storage mechanisms and the latest advancements in high-energy-density LMBs, represented by systems such as Li–Li1−xMO2, Li–S/Se, Li–gas (CO2/air/O2), Li–CFx, and all-solid-state LMBs. By integrating the current research findings, we highlight the opportunities and future research directions for high-energy-density LMBs, offering new guiding perspectives for their development under practical conditions. [ABSTRACT FROM AUTHOR]

There are some connections between aging notions, stochastic orders, and expected utilities. It is known that the DRHR (decreasing reversed hazard rate) aging notion can be characterized via the comparative statics result of risk aversion, and that the location-independent riskier order preserves monotonicity between risk premium and the Arrow–Pratt measure of risk aversion, and that the dispersive order preserves this monotonicity for the larger class of increasing utilities. Here, the aging notions ILR (increasing likelihood ratio), IFR (increasing failure rate), IGLR (increasing generalized likelihood ratio), and IGFR (increasing generalized failure rate) are characterized in terms of expected utilities. Based on these observations, we recover the closure properties of ILR, IFR, and DRHR under convolution, and of IGLR and IGFR under product, and investigate the closure properties of the dispersive order, location-independent riskier order, excess wealth order, the total time on test transform order under convolution, and the star order under product. We have some new findings. [ABSTRACT FROM AUTHOR]

The coverage of *CO and *H intermediates on the surface of a catalyst plays a pivotal role in determining the selectivity towards C1 or C2 products in the electrochemical CO2 reduction reaction (CO2RR). In this study, we engineered two types of interfaces involving copper and rare earth metal oxides, specifically Cu/CeOx and Cu/CuCeOx solid solution, which exhibit enhanced binding affinities for *H and *CO adsorbates in the CO2RR, respectively. As a result, the Cu/CuCeOx catalyst delivered an ethylene faradaic efficiency of 40.2% at a partial current density of −245.7 mA cm−2, whereas the Cu/CeOx catalyst presented a methane faradaic efficiency of 38.6% at a partial current density of −198.3 mA cm−2. Results of theoretical and experimental analyses have demonstrated that the Cu–Ce–Ox solid solution markedly enhances *CO adsorption by stabilizing Cu+ species, thereby favoring its dimerization to ethylene rather than converting to methane through hydrogenation. This investigation elucidates a strategy for directing the selective electroproduction of C1 or C2 compounds from the CO2RR by effectively manipulating *H and *CO adsorption on Cu/CeOx catalysts. [ABSTRACT FROM AUTHOR]

The accumulation of excessive nitrate in the atmosphere not only jeopardizes human health but also disrupts the balance of the nitrogen cycle in the ecosystem. Among various nitrate removal technologies, electrocatalytic nitrate reduction reaction (eNO3RR) has been widely studied for its advantages of being eco-friendly, easy to operate, and controllable under environmental conditions with renewable energy as the driving force. Transition metal-based catalysts (TMCs) have been widely used in electrocatalysis due to their abundant reserves, low costs, easy-to-regulate electronic structure and considerable electrochemical activity. In addition, TMCs have been extensively studied in terms of the kinetics of the nitrate reduction reaction, the moderate adsorption energy of nitrogen-containing species and the active hydrogen supply capacity. Based on this, this review firstly discusses the mechanism as well as analyzes the two main reduction products (N2 and NH3) of eNO3RR, and reveals the basic guidelines for the design of efficient nitrate catalysts from the perspective of the reaction mechanism. Secondly, this review mainly focuses on the recent advances in the direction of eNO3RR with four types of TMCs, Fe, Co, Ni and Cu, and unveils the interfacial modulation strategies of Fe, Co, Ni and Cu catalysts for the activity, reaction pathway and stability. Finally, reasonable suggestions and opportunities are proposed for the challenges and future development of eNO3RR. This review provides far-reaching implications for exploring cost-effective TMCs to replace high-cost noble metal catalysts (NMCs) for eNO3RR. [ABSTRACT FROM AUTHOR]

Energy storage devices play a crucial role in various applications, such as powering electronics, power backup for homes and businesses, and support for the integration of renewable energy sources into electrical grid applications. Electrode materials for energy storage devices are preferred to have a flexible nature, conductive, better capacity, and low‐toxicity. Using Gallium based liquid metal alloys, such as Eutectic Gallium‐Indium (EGaIn), Eutectic Gallium‐Tin (EGaSn), and Eutectic Gallium‐Indium‐Tin (EGaInSn), as electrode materials play very important role in energy storage devices. These liquid metals have some interesting properties with a self‐healing nature, high mechanical stability, compatibility with various materials, fluidity, low young's modulus, high electrical and thermal conductivity. Those properties have made it suitable to be used in various energy storage devices. In this mini review, we have concisely described the advantages and challenges of using liquid metal as electrode materials for various energy storage devices. [ABSTRACT FROM AUTHOR]