The electrochemical nitrate reduction reaction (NO3RR) to ammonia offers a sustainable pathway for nitrogen cycling and energy storage. The efficiency of this spin-related reaction is fundamentally limited by the sluggish hydrogenation of the *NO intermediate, where spin-state transitions of the catalysts present a pivotal bottleneck. Herein, Co3O4/CuO heterostructures were constructed, wherein the interfacial d-orbital coupling induced a spin- modulated electronic rearrangement. This catalyst achieved a superior NH3 yield rate of 8.21 mg & sdot;h1 & sdot;cm2 & sdot;mgcat1 with a Faradaic efficiency of 95.5% at 0.4 VRHE, one of the highest reported performances. The EXAFS, low- temperature EPR, XANES, XPS, KPFM, and the density functional theory (DFT) calculations reveal a strong heterointerface interaction, as well as the triggered electron spin polarization and local charge redistribution. The reconfigured electronic structure not only stabilizes the *NO intermediate but also drastically reduces the energy barrier for its hydrogenation, as validated by in situ electrochemical impedance spectroscopy (EIS) and reaction pathway analysis. This work establishes a pioneering paradigm of "heterointerface spin polarization engineering" to enhance the NO3RR kinetics and provide a versatile strategy for the design of high-performance electrocatalysts for spin-related reactions.

Dry reforming of methane (DRM) offers a promising route for syngas production while mitigating two greenhouse gases (CH4 and CO2). However, the surface thermodynamics of reactant adsorption remain elusive due to the lack of quantitative tools. Herein, we synthesize self-supporting hollow Al2O3 nanofibers decorated with Ni, NiCo, and NiCu alloys via blow spinning, eliminating the need for pelletization. Among these, NiCo/Al2O3 exhibits superior activity (85% CH4 conversion at 800 degrees C) and coking resistance (0.84 wt% carbon after 50 h). For the first time, we quantify the adsorption enthalpies of CH4, CO2, and H2 on these catalysts using gas adsorption calorimetry. Notably, CH4-a stable tetrahedral molecule-chemisorbs exothermically on Ni sites at 298 K, with enthalpies of -55.2 (NiCo), -78.2 (NiCu), and -87.5 kJ mol- 1 (Ni). A strong structure-enthalpy-activity correlation emerges: overly exothermic adsorption hinders catalytic turnover by stabilizing surface intermediates. This thermodynamic framework provides a lens to rationally design DRM catalysts.

Anion exchange membranes (AEMs) are critical components in anion exchange membrane water electrolysis (AEMWE), determining green hydrogen production efficiency via their ionic conductivity, chemical stability, and mechanical robustness. In this study, a series of s-BPTTP-x membranes are fabricated for AEMWE by integrating a branched architecture and dual-cation grafting with tunable substitution degrees, in which the rigid tetraphenylmethane (TPM) branching units disrupts polymer chain packing, increasing free volume and microporous stability, while the dual-quaternary ammonium side chains optimize ion channels and promote microphase separation. Particularly, the s-BPTTP-80 membrane delivers an OH- conductivity of 168.52 mS cm- 1 at 80 degrees C with a swelling ratio of 20.48%, outperforming the linear counterpart s-PTP-80 (137.5 mS cm-1, 32.5% swelling). It also exhibits a tensile strength of 34.79 MPa and elongation at break of 22.6%, higher than those of s-PTP-80 (26.93 MPa, 17.4%). In an AEMWE single cell, s-BPTTP-80 achieves a current density of 1530 mA cm- 2 at 2.0 V and 80 degrees C with an ohmic resistance of 57 m Omega cm2, and shows a voltage decay rate of 0.26 mV h- 1 over 1000 h at 500 mA cm- 2, which is lower than that of FAA-3-50 (0.45 mV h-1). The "rigid branching-functional side chain" design strategy provides a practical approach for high-performance AEMs toward sustainable hydrogen production.

It is a critical challenge for sustainable energy technologies to develop a highly-active non-noble bifunctional catalyst for both electrocatalytic and photoelectrocatalytic water splitting. Herein, an ordered mesoporous CoP has been synthesized by nano-casting method as a bifunctional catalyst for overall water splitting with a low driving voltage of 1.656 V at 10 mA cm- 2 in 1 M KOH electrolyte. A dual-photoelectrodes system has been further constructed by coating of the as-synthesized CoP catalyst on Si-based semiconductors. The composite photocathode and photoanode exhibit photon-to-current efficiencies of 5.16 % and 2.78 % under simulated AM 1.5G irradiation, respectively. A solar-to-hydrogen efficiency of 3.54 % is obtained in a series-structured photoelectrochemical cell. This work provides theoretical guidance for the preparation of mesoporous materials and the construction of dual-photoelectrode system.

Electrochemical water splitting is a promising method for generating green hydrogen gas, offering a sustainable approach to addressing global energy challenges. However, the sluggish kinetics of the anodic oxygen evolution reaction (OER) poses a great obstacle to its practical application. Recently, increasing attention has been focused on introducing various external stimuli to modify the OER process. Despite significant enhancement in catalytic performance, an in-depth understanding of the origin of superior OER activity contributed by the external stimuli remains elusive, which significantly hinders the further development of highly efficient and durable water electrolyzed devices. Herein, this review systematically summarizes the recent advancements in the understanding of various external stimuli, including photon irradiation, applied magnetic field, and thermal heating, etc., to boost OER activities. In particular, the underlying mechanisms of external stimuli to promote species transfer, modify the electronic structure of electrocatalysts, and accelerate structural reconstruction are highlighted. Additionally, applications of external stimuli in other electrocatalytic reactions are also presented. Finally, several remaining challenges and future opportunities are discussed, providing insights that could further the study of external stimuli in electrocatalytic reactions and support the rational design of highly efficient energy storage and conversion devices.

An internal resistance heating method was proposed to control the operating temperature of Li-ion batteries to address rapid performance degradation under low temperature conditions. Main research content: (a) Preparation and process optimization of PTC (positive temperature coefficient) effects materials: Using micrometer nickel powder as the conductive material and polypropylene/polyvinylidene fluoride (PP/PVDF) as the polymer matrix. The polymer matrix was mixed with the conductive material using high-temperature melting method. The PTC materials with a transition temperature below 40°C were prepared through controlling the preparation process repeatedly and meticulously, and the optimal preparation process was determined. (b) Performance testing and analysis of PTC materials: The thermal analysis, volume change analysis, structure and micro-structure analysis were conducted through resistivity temperature curve, tensile performance, SEM and thermal expansion testing, respectively. The influence of conductive material content, heat treatment temperature, heat treatment time on the performance of PTC materials was systematically studied. (c) “Self heating Battery” assembly and performance study: A self heating Li-ion battery was assembled and its electrochemical performance was tested systematically. The results showed that the low-temperature discharge performance of the battery was significantly improved. This work can help improve the low-temperature performance of Li-ion batteries and expand its application areas.

As a graphene-like layered material, molybdenum disulfide (MoS2), has attracted increasing attentions for its promising application in electrocatalysis. Whereas MoS2 still suffers from the sluggish reaction kinetics in oxygen evolution reaction (OER) due to the low density of active sites in most exposed planes. In this work, high density of active sites on MoS2 basal planes has been obtained by synthesizing mesoporous MoS2 with Co doping and sulfur vacancies (VS). The synergy of the mesoporous structure, Co doping, and sulfur vacancies resulted in optimized bifunctional electrocatalytic activity for both hydrogen evolution reaction (HER) and OER in alkaline media. The overpotential required to achieve a current density of 10 mA cm-2 (denoted as ti10) is 34 mV for HER and 268 mV for OER, respectively. The two-electrode electrolyzer constructed with the as-prepared cobalt-doped mesoporous MoS2 electrodes exhibited a low bias (ti10 = 1.58 V) for overall water splitting. Density functional theory (DFT) calculations confirm the significance of Co doping and the S vacancy defects, which lowers the Gibbs free energy (Delta G) for the formation of the corresponding intermediates.

The regions of edge and corner of the catalyst are crucial for the intermediates adsorption during the electrocatalytic oxygen evolution reaction (OER). The challenge remains in optimizing the exposed region of catalysts and modulating the adsorption strength of intermediates. Herein, a novel transition metal phosphide (TMP) composite nanostructure, with cobalt-iron phosphide (CoFeP) cubes in core and iron phosphide (FeP) satellite particles on the corners, was successfully synthesized via a non-spontaneous crystallization strategy. The precursor growth mechanism of the Prussian blue analogues (PBAs) from coordination chemistry and supersaturation theory was proposed according to non-in situ observation experiments. By selective wrapping of corners and/or edges on the cubes with controlled deposition of FeP, the electrocatalytic performance of the CoFeP cubes was significantly boosted to varying degrees. The optimized core-satellite phosphide composites exhibited an overpotential of 256 mV for the current density of 10 mA cm- 2 (commercial ruthenium oxide: 282 mV at 10 mA cm- 2) and stability over 200 h at 100 mA cm- 2. The detection of *OH intermediates and the DFT simulations confirmed the appropriate adsorption strength for *OH upon formation of iron phosphide satellites on the corners. Therefore, the core-satellite heterostructures with selectively passivated corners could attain low reaction barriers of the rate determining step, fast reaction kinetics, and good stability.

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Polarizing carbon substrate by heteroatom-doping has been verified as an effective strategy to suppress shuttling effect of lithium-sulfur batteries (LSBs). Polyacenes (PAs) derived from phenol-formaldehyde resin with controllable porous structure and high conductivity has been broadly integrated into lithium-ion batteries as conductivity coating material. Herein, a nitrogen and phosphorus co-doped polyacenes (NP-PAs) material was prepared for LSBs. The disordered mesoporous structure and high electronic conductivity of NP-PAs makes it suitable for sulfur host and plays the role of physical confinement. The polarized surface of NP-PAs further alleviates the shuttling effect. As a result, the NP-PAs/S cathode successfully meliorates the inherent vice of sulfur containing cathode, and presents elevated rate capabilities and robust long cycling stability (677.6 mAh/g of the 400th cycle at 1C with small average capacity attenuation of 0.071% for each cycle).

An electrochemical CO2 reduction reaction (CO2RR) is an effective way to reduce greenhouse gases by converting CO2 into high-value-added chemical products using electricity generated from renewable energy. In this paper, a Cu2O spherical catalyst was prepared by ascorbic acid reduction. The precipitated Cu-Ag spherical catalyst (P-CuO-Ag) was successfully prepared by calcining Cu2O-Ag with the introduction of an Ag component as the substrate. During the electrochemical reduction of CO2, the FE of the P-CuO-Ag catalyst for C2H4 at a potential of −1.1 V vs. RHE was as high as 39.8%, which was nearly twice that of the CuO catalyst, while the local current density JC2H4 for C2H4 reached 6 mA cm−2. The incorporation of Ag gives the spherical CuO catalyst higher electrochemical activity and better kinetic performance than the catalyst without Ag.

A new type of Ni/Al2O3 self-supporting catalysts, with high specific surface area, was fabricated by blow-spinning technology. These Ni/Al2O3 self-supporting catalysts are hollow flexible fibers and were utilized for the dry reforming of methane. The Ni/Al2O3 catalysts exhibited exceptional catalytic performance, maintaining their activity for over 150-h at a high temperature of 800 degrees C. The Ni nanoparticles disputed on the hollow fibers demonstrated remarkable resistance to sintering and coking during high-temperature catalysis. This was a noteworthy feature, as sintering and coking are common challenges faced by catalysts during high-temperature reactions. Furthermore, the catalysts retained its activity even after a rigorous 150-h test at 800 degrees C, indicating its durability and stability. Importantly, the Ni/Al2O3 self-supporting could be successfully reactivated after the test, further highlighting its reusable nature. This study offers promising new avenues for the development of high-temperature, self-supporting, and reactivatable catalysts.

A nitrogen-phosphorus dual-doped auricularia auricula carbon (NP-AC) matrix was prepared through hydrothermal treatment using natural auricularia auricula as raw material and medium solution. Yeast was introduced and cultured by the auricularia auricula liquid medium. The NP-AC/S composite was prepared through further freeze-drying, carbonization, activation and compounding with sulfur procedures. The composition and microstructure of samples was characterized by X-ray diffraction (XRD), raman and X-ray photoelectron spectroscopy (XPS). The morphology was observed under scanning electron microscope (SEM) and transmission electron microscopy (TEM) method. The specific surface area was analyzed using nitrogen adsorption/desorption test. The weight ratio of sulfur was measured through thermogravimetric (TG) analysis. The original structure and composition of biomass were improved by yeast fermentation and the auricularia auricula block structure with low porosity was modified. The electrochemical performance of NP-AC/S composite in Li-S batteries was systematically explored. After 100 cycles at 0.2C current density, there was still nearly 1000 mAh g−1 reversible capacity, holding a capacity retention rate of more than 84 %. The cycle performance and rate performance were both far better than the ordinary activated carbon materials.

The development of electrocatalysts with low cost, high efficiency, and long-term durability is crucial for advancing green hydrogen production. Transition metal phosphides (TMPs) have been proved to be efficient electrocatalyst, while the improvement in the performance and durability of the TMPs remains a big challenge. Employing atmospheric pressure chemical vapor deposition (APCVD) and phosphorization, FeP/Ti electrodes are fabricated featuring controllable oxygen ingredients (O-FeP/Ti). This manipulation of oxygen content fine-tunes the electronic structure of the catalyst, resulting in improved surface reaction kinetics and catalytic activity. The optimized O-FeP-400/Ti exhibits outstanding HER activity with overpotentials of 142 and 159 mV at -10 mA cm-2 in 0.5 M H2SO4 and 1 M KOH, respectively. Notably, the obtained O-FeP/Ti cathode also displays remarkable durability of up to 200 h in acidic electrolyte with surface topography remaining intact. For the first time, the low-valence titanium oxide (Ti3O) interlayer is identified in the composite electrode and ascribed for the superior connection between Ti substrate and the surface O-FeP catalyst, as supported by experimental results and density functional theory (DFT) analysis. This work has expanded the potential applications of transition metal phosphides (TMPs) as a cost-effective, highly efficient and durable catalyst for water splitting.

Non-firing functional oxide materials are attracting significant interest due to their suitability for a wide range of applications, particularly in thermal, electrical, and architectural fields. These materials, which range from natural to synthetic forms, offer a diverse range of properties. While oxides are generally known for their high mechanical strength, temperature resistance, and cost-effectiveness, traditional oxide processing often requires energy-intensive and environmentally unfriendly high-temperature sintering. Therefore, the investigation of energy-efficient non-firing mechanisms for oxides is not only beneficial but crucial. This paper reviews the advancements in non-firing mechanisms, with a focus on material selection, synthesis processes, and potential applications. Special attention is given to non-firing forms such as silica-based and geopolymer materials, which are prepared using low-energy acid-base reactions with either natural or synthetic silica-alumina sources. The review also encapsulates the challenges and solutions associated with these sustainable, non-firing oxide materials.

A nitrogen-phosphorus dual-doped porous spore carbon (NP-PSC) positive electrode matrix was prepared using native auricularia auricula as solid medium based on the principle of biomass rot. Yeast was introduce and cultured by the auricularia auricula solid medium. The freeze-drying and carbonization activation processes made the materials present a three-dimensional porous spore carbon aerogel properties. Yeast fermentation transformed auricularia auricula from blocky structure to porous structure and introduced nitrogen-phosphorus dual-doping. The physical and chemical properties of the prepared materials were characterized in detail. Electrochemical performance of NP-PSC in Li-S batteries was systematically investigated. Porous structure and heteroatom-doping improved the electrochemical performance, which is much superior to conventional activated carbon materials.

Silicon (Si) photocathode with surface decoration of co-catalysts is a promising material for green hydrogen production. The surface of the Si is often further etched into pyramids for optical absorption. However, the photon-generated charges tend to concentrate on the pyramid peaks, whilst the catalyst of nanoparticles generally aggregate in the valley, where less charges are available. In this work, one-dimensional tungsten oxide (WOx) x ) with an ultra-thin layer of carbon species have been used as the cocatalyst, which preferentially stay on the upperpart of the pyramids with intimate contact. WOx x has great potential in catalysis for hydrogen evolution reaction (HER) due to its ideal proton adsorption/desorption behavior. However, WOx, x , especially in form of nanorods, has rarely been reported as cocatalysts for photo(electro)catalysis, due to the challenges in the preparation and stabilities during long-term HER catalysis. Herein, the formation of WOx-C x-C nanorods was induced, leading to improved conductivity and stability as co-catalysts. The density functional theory (DFT) calculations revealed the low reaction free energy of WOx-C x-C co-catalysts and the smooth electrons transfer from W to protons. The Si photocathodes deposited with the optimized WOx-C x-C hybrids nanorods showed high performance in PEC reaction, achieving a current density of-21.3 mA center dot cm- center dot cm- 2 at 0 V RHE and an onset potential of +0.218 V RHE under acidic conditions. The catalytic mechanism of WOx-C x-C nanorods for the pyramidal Si- photocathode is investigated and proposed.

Bimetallic Pt/Ag nanoparticles (Pt/Ag NPs) were synthesized using 3-hydroxyphenyl-boronic acid as the reducing and stabilizing agent by a simple, one-step hydrothermal method. The bimetallic Pt/Ag NPs were demonstrated to possess intrinsic peroxidase mimetic catalytic activity for the luminol/H2O2 reaction to generate chemiluminescence (CL). The catalytic properties of the bimetallic Pt/Ag NPs were thoroughly investigated. The results showed that the combination of Pt and Ag greatly enhanced the chemiluminescence which is attributed to their synergy. Moreover, the prepared bimetallic Pt/Ag NPs exhibited superior peroxidase mimetic activity to horseradish peroxidase and were stable under a wide range of pH values and temperatures. Using the bimetallic Pt/Ag NPs as the catalyst, a novel chemiluminescence sensor was developed for the determination of glucose with a linear range from 1 to 500 mu M and a detection limit of 0.35 mu M. The developed method was successfully employed to determine glucose in human serum with satisfactory results. Bimetallic Pt/Ag NPs with peroxidase mimetic catalytic activity have promising applications for determination of glucose in clinical samples.

Rechargeable aqueous alkali-ion batteries are of great interest in cost-effective, risk-free and green energy-storage technologies. Although redox-active organic compounds are regarded as a kind of promising electrode materials, the limited capacity and low charge-transfer capability still hinder their applications in aqueous alkaliion batteries. Herein, we have designed a cyano-substituted diquinoxalinophenazine (3CN-DPZ) organic electrode. For the first time, in-operando monitoring techniques, i.e., in-situ Raman and in-situ FTIR investigations, combined with the theoretical calculations are thoroughly carried out to explore the role of electron-withdrawing cyano substituents in 3CN-DPZ organic electrode for aqueous Na+ storage. It is demonstrated that the introduced cyano groups provide redox-active sites for the 3CN-DPZ organic electrode upon Na+ uptake/removal and have the strong electron absorption ability coordinated with Na+ in aqueous electrolyte. Therefore, the 3CN-DPZ organic electrode delivers a large specific capacity of 305.1 mAh/g at 1 A/g, a high rate capability of 211.3 mAh/g at 64 A/g, and an exceptional cycling retention of - 97.9 % over 5000 cycles. Furthermore, a high-performance aqueous Na-ion battery (ANIB) has been fabricated with considerable energy/power characteristics and long cycling lifespan, revealing its potential scalable applications in satisfying the various requirements of high-safety and low-cost energy storage systems.