Platinum-Ruthenium Dual-Atomic Sites Dispersed in Nanoporous Ni0.85Se Enabling Ampere-Level Current Density Hydrogen Production.

Alkaline anion-exchange-membrane water electrolyzers (AEMWEs) using earth-abundant catalysts is a promising approach for the generation of green H2. However, the AEMWEs with alkaline electrolytes suffer from poor performance at high current density compared to proton exchange membrane electrolyzers. Here, atomically dispersed Pt-Ru dual sites co-embedded in nanoporous nickel selenides (np/Pt1Ru1-Ni0.85Se) are developed by a rapid melt-quenching approach to achieve highly-efficient alkaline hydrogen evolution reaction. The np/Pt1Ru1-Ni0.85Se catalyst shows ampere-level current density with a low overpotential (46 mV at 10 mA cm-2 and 225 mV at 1000 mA cm-2), low Tafel slope (32.4 mV dec-1), and excellent long-term durability, significantly outperforming the benchmark Pt/C catalyst and other advanced large-current catalysts. The remarkable HER performance of nanoporous Pt1Ru1-Ni0.85Se is attributed to the strong intracrystal electronic metal-support interaction (IEMSI) between Pt-Se-Ru sites and Ni0.85Se support which can greatly enlarge the charge redistribution density, reduce the energy barrier of water dissociation, and optimize the potential determining step. Furthermore, the assembled alkaline AEMWE with an ultralow Pt and Ru loading realizes an industrial-level current density of 1 A cm-2 at 1.84 volts with high durability.

Constructing Nanoporous Ir/Ta2 O5 Interfaces on Metallic Glass for Durable Acidic Water Oxidation.

Although proton exchange membrane water electrolyzers (PEMWE) are considered as a promising technique for green hydrogen production, it remains crucial to develop intrinsically effective oxygen evolution reaction (OER) electrocatalysts with high activity and durability. Here, a flexible self-supporting electrode with nanoporous Ir/Ta2O5 electroactive surface is reported for acidic OER via dealloying IrTaCoB metallic glass ribbons. The catalyst exhibits excellent electrocatalytic OER performance with an overpotential of 218 mV for a current density of 10 mA cm-2 and a small Tafel slope of 46.1 mV dec-1 in acidic media, superior to most electrocatalysts. More impressively, the assembled PEMWE with nanoporous Ir/Ta2 O5 as an anode shows exceptional performance of electrocatalytic hydrogen production and can operate steadily for 260 h at 100 mA cm-2 . In situ spectroscopy characterizations and density functional theory calculations reveal that the modest adsorption of OOH* intermediates to active Ir sites lower the OER energy barrier, while the electron donation behavior of Ta2 O5 to stabilize the high-valence states of Ir during the OER process extended catalyst's durability.

Tuning Crystal Phase of Palladium-Selenium Nanowires for Enhanced Ethylene Glycol Electrocatalytic Oxidation.

Alcohol electrooxidation is pivotal for a sustainable energy economy. However, designing efficient electrocatalysts for this process is still a formidable challenge. Herein, palladium-selenium nanowires featuring distinct crystal phases: monoclinic Pd7Se2 and tetragonal Pd4.5Se for ethylene glycol electrooxidation reaction (EGOR) are synthesized. Notably, the supported monoclinic Pd7Se2 nanowires (m-Pd7Se2 NWs/C) exhibit superior EGOR activity, achieving a mass activity (MA) and specific activity (SA) of 10.4 A mgPd -1 (18.7 mA cm-2), which are 8.0 (6.7) and 10.4 (8.2) times versus the tetragonal Pd4.5Se and commercial Pd/C and surpass those reported in the literature. Furthermore, m-Pd7Se2 NWs/C displays robust catalytic activity for other alcohol electrooxidation. Comprehensive characterization and density functional theory (DFT) calculations reveal that the enhanced electrocatalytic performance is attributed to the increased formation of Pd0 on the high-index facets of the m-Pd7Se2 NWs, which lowers the energy barriers for the C─C bond dissociation in CHOHCHOH* and the CO* oxidation to CO2*. This study provides palladium-based alloy electrocatalysts exhibiting the highest mass activity reported to date for the electrooxidation of ethylene glycol, achieved through the crystalline phase engineering strategy.

Asymmetric Local Electric Field Induced by Dual Heteroatoms on Copper Boosts Efficient CO2 Reduction Over Ultrawide Potential Window.

Electrocatalytic reduction of CO2 powered by renewable electricity provides an elegant route for converting CO2 into valuable chemicals and feedstocks, but normally suffers from a high overpotential and low selectivity. Herein, Ag and Sn heteroatoms were simultaneously introduced into nanoporous Cu (np-Ag/Sn-Cu) mainly in the form of an asymmetric local electric field for CO2 electroreduction to CO in an aqueous solution. The designed np-Ag/Sn-Cu catalyst realizes a recorded 90% energy efficiency and a 100% CO Faradaic efficiency over ultrawide potential window (ΔE = 1.4 V), outperforming state-of-the-art Au and Ag-based catalysts. Density functional theory calculations combined with in situ spectroscopy studies reveal that Ag and Sn heteroatoms incorporated into Cu matrix could generate strong and asymmetric local electric field, which promotes the activation of CO2 molecules, enhances the stabilization of the *COOH intermediate, and suppresses the hydrogen evolution reaction, thus favoring the production of CO during CO2RR.

Unveiling the Proton-Feeding Effect in Sulfur-Doped Fe-N-C Single-Atom Catalyst for Enhanced CO2 Electroreduction.

Heteroatom-doping in metal-nitrogen-carbon single-atom catalysts (SACs) is considered a powerful strategy to promote the electrocatalytic CO2 reduction reaction (CO2 RR), but the origin of enhanced catalytic activity is still elusive. Here, we disclose that sulfur doping induces an obvious proton-feeding effect for CO2 RR. The model SAC catalyst with sulfur doping in the second-shell of FeN4 (Fe1 -NSC) was verified by X-ray absorption spectroscopy and aberration-corrected scanning transmission electron microscopy. Fe1 -NSC exhibits superior CO2 RR performance compared to sulfur-free FeN4 and most reported Fe-based SACs, with a maximum CO Faradaic efficiency of 98.6 % and turnover frequency of 1197 h-1 . Kinetic analysis and in situ characterizations confirm that sulfur doping accelerates H2 O activation and feeds sufficient protons for promoting CO2 conversion to *COOH, which is also corroborated by the theoretical results. This work deepens the understanding of the CO2 RR mechanism based on SAC catalysts.

Heteroatoms Induce Localization of the Electric Field and Promote a Wide Potential-Window Selectivity Towards CO in the CO2 Electroreduction.

Carbon dioxide electroreduction (CO2 RR) is a sustainable way of producing carbon-neutral fuels. Product selectivity in CO2 RR is regulated by the adsorption energy of reaction-intermediates. Here, we employ differential phase contrast-scanning transmission electron microscopy (DPC-STEM) to demonstrate that Sn heteroatoms on a Ag catalyst generate very strong and atomically localized electric fields. In situ attenuated total reflection infrared spectroscopy (ATR-IR) results verified that the localized electric field enhances the adsorption of *COOH, thus favoring the production of CO during CO2 RR. The Ag/Sn catalyst exhibits an approximately 100 % CO selectivity at a very wide range of potentials (from -0.5 to -1.1 V, versus reversible hydrogen electrode), and with a remarkably high energy efficiency (EE) of 76.1 %.

Effects of self-efficacy on frontal midline theta power and golf putting performance.

Introduction: Self-efficacy (SE), defined as an individual's belief in their ability to complete a task, is linked to top-down attentional control, influencing motor performance in sports. Although the behavioral effects of SE are well-documented, there is a lack of research on the mechanisms through which SE affects sports performance. Our research aims to elucidate the neurophysiological mechanisms that underlie the impact of self-efficacy on sports performance. Specifically, we intend to explore the effects of low and high SE on frontal midline theta (Fmθ) activity, associated with sustained top-down attention, and on motor performance. Methods: We recruited thirty-four professional golfers to perform 60 putts, during which their electroencephalographic activity was monitored. SE levels were assessed using a visual analog scale from 0 to 10 before each putt, with scores categorized into higher or lower SE based on each golfer's individual average score. Results: Paired t-tests indicated that trials with higher SE scores had a higher putting success rate than those with lower SE scores (53.3% vs. 46.7%). Furthermore, trials associated with higher SE scores exhibited lower Fmθ activity compared to those with lower SE scores (4.49 vs. 5.18). Discussion: Our results suggest that higher SE is associated with reduced top-down attentional control, leading to improved putting performance. These findings support Bandura's theory of SE, which suggests that the effects of efficacy beliefs are mediated by cognitive, motivational, emotional, and decision-making processes. This study sheds light on the intermediate processes of SE by examining its impact on the anticipation of outcomes, sports performance, and attentional control prior to putting.

Local Construction of Mn-Based Layered Cathodes through Covalency Modulation for Sodium-Ion Batteries.

P2-type Mn-based layered oxides are among the most prevalent cathodes for sodium-ion batteries (SIBs) owing to their low cost, resource abundance, and high theoretical specific capacity. However, they usually suffer from Jahn-Teller (J-T) distortion from high-spin Mn3+ and poor cycling stability, resulting in rapid degradation of their structural and electrochemical properties. Herein, a stable P2-type Mn-based layered oxide is realized through a local construction strategy by introducing high-valence Ru4+ to overcome these issues. It has been revealed that the Ru substitution in the as-constructed Na0.6Mg0.3Mn0.6Ru0.1O2 (NMMRO) renders the following favorable effects. First, the detrimental P2-OP4 phase transition is effectively inhibited owing to the robust Ru-O covalency bond. Second, the Mg/Mn ordering is disturbed and the out-of-plane displacement of Mg2+ and in-plane migration of Mn4+ are suppressed, leading to improved structural stability. Third, the redox ability of Mn is increased by weakening the covalence between Mn and O through the local Ru-O-Mn configurations, which contributes to the attenuated J-T distortion. Last, the strong Ru-O covalency bond also leads to enhanced electron delocalization between Ru and O, which decreases the oxidation of oxygen anion and thereby reduces the driving force of metal migration. Because of these advantages, the structural integrity and electrochemical properties of NMMRO are largely improved compared with the Ru-free counterpart. This work provides deeper insights into the effect of local modulation for cationic/anionic redox-active cathodes for high-performance SIBs.

Origin of the Seriously Limited Anionic Redox Reaction of Li-Rich Cathodes in Sulfide All-Solid-State Batteries.

Li-rich layered oxide (LLO) cathode materials with mixed cationic and anionic redox reactions display much higher specific capacity than other traditional layered oxide materials. However, the practical specific capacity of LLO during the first cycle in sulfide all-solid-state lithium-ion batteries (ASSLBs) is extremely low. Herein, the capacity contribution of each redox reaction in LLO during the first charging process is qualitatively and quantitatively analyzed by comprehensive electrochemical and structural measurements. The results demonstrate that the cationic redox of the LiTMO2 (TM = Ni, Co, Mn) phase is almost complete, while the anionic redox of the Li2MnO3 phase is seriously limited due to the sluggish transport kinetics and severe LLO/Li6PS5Cl interface reaction at high voltage. Therefore, the poor intrinsic conductivity and interface stability during the anionic redox jointly restrict the capacity release or delithiation/lithiation degree of LLO during the first cycle in sulfide ASSLBs. This study reveals the origin of the seriously limited anionic redox reaction in LLO, providing valuable guidance for the bulk and interface design of high-energy-density ASSLBs.

Mg Substitution Induced TM/Vacancy Disordering and Enhanced Structural Stability in Layered Oxide Cathode Materials.

Anionic redox is an effective way to increase the capacity of the cathode materials. Na2Mn3O7 [Na4/7[Mn6/7□1/7]O2, □ for the transition metal (TM) vacancies] with native and ordered TM vacancies can conduct a reversible oxygen redox and be a promising high-energy cathode material for sodium-ion batteries (SIBs). However, its phase transition at low potentials (∼1.5 V vs Na+/Na) induces potential decays. Herein, magnesium (Mg) is doped on the TM vacancies to form a disordered Mn/Mg/□ arrangement in the TM layer. The Mg substitution suppresses the oxygen oxidation at ∼4.2 V by reducing the number of the Na-O-□ configurations. Meanwhile, this flexible disordering structure inhibits the generation of the dissolvable Mn2+ ions and mitigates the phase transition at ∼1.6 V. Therefore, the Mg doping improves the structural stability and its cycling performance in 1.5-4.5 V. The disordering arrangement endows Na0.49Mn0.86Mg0.06□0.08O2 with a higher Na+ diffusivity and improved rate performance. Our study reveals that oxygen oxidation is highly dependent on the ordering/disordering arrangements in the cathode materials. This work provides insights into the balance of anionic and cationic redox for enhancing the structural stability and electrochemical performance in the SIBs.

Surface Defect Engineering of a Bimetallic Oxide Precatalyst Enables Kinetics-Enhanced Lithium-Sulfur Batteries.

Developing efficient electrocatalysts to accelerate the sluggish conversion of lithium polysulfides (LiPSs) is of paramount importance for improving the performances of lithium-sulfur (Li-S) batteries. However, a consensus has not yet been reached on the in situ evolution of the electrocatalysts as well as the real catalytic active sites. Herein, defective MnV2O6 (D-MVO) is designed as a precatalyst toward LiPSs' adsorption and conversion. We reveal that the introduction of surface V defects can effectively accelerate the in situ sulfurization of D-MVO during the electrochemical cycling process, which acts as the real electrocatalyst for LiPSs' retention and catalysis. The in situ-sulfurized D-MVO demonstrates much higher electrocatalytic activity than the defect-free MVO toward LiPSs' redox conversion. With these merits, the Li-S batteries with D-MVO separators achieve superior long-term cycling performance with a low decay rate of 0.056% per cycle after 1000 cycles at 1C. Even under an elevated sulfur loading of 5.5 mg cm-2, a high areal capacity of 4.21 mAh cm-2 is still retained after 50 cycles at 0.1C. This work deepens the cognition of the dynamic evolution of the electrocatalysts and provides a favorable strategy for designing efficient precatalysts for advanced Li-S batteries using defect engineering.