Tuning lattice oxygen participation to govern OER activity in metal oxides.

Stabilizing Co-free Li-rich cathodes with LaF3 coating and ionic liquid electrolytes: A pathway to high-performance lithium-ion batteries.

The study utilized litchi shells as precursors to synthesize N, S self-doped carbon quantum dots (LBCQDs) by a hydrothermal method for use as corrosion inhibitors. Electrochemical testing, weight loss tests, surface characterization, and density functional theory calculations were employed to investigate the corrosion inhibition performance of LBCQDs on 5052 aluminum alloy in the HCl solution. The results indicate that LBCQDs are a mixed-type corrosion inhibitor, predominantly inhibiting cathodic reactions. Their corrosion inhibition efficiency increases with concentration, reaching a maximum of 94.22% at a concentration of 300 mg·L-1. In addition, higher concentrations of LBCQDs result in a slower reduction in corrosion inhibition efficiency over a prolonged immersion time. The corrosion inhibition mechanism analysis indicates that LBCQDs can spontaneously form a protective film on the aluminum alloy surface based on the synergistic effects of physical adsorption, chemical adsorption, aggregation effect, and the chelation reaction. This increases the energy barrier of the corrosion reaction of the aluminum alloy, thereby inhibiting corrosion. This work not only provides a high-value utilization strategy for litchi shell biomass but also offers profound insights for designing eco-friendly corrosion inhibitors.

In the construction of sustainable energy systems, the development of efficient and stable electrocatalysts for the hydrogen evolution reaction (HER) is of crucial significance. This study adopts an in situ oxidation-nitridation strategy to successfully construct a Ni3N/NiO heterostructured catalyst with a three-dimensional hierarchical structure. In this catalyst, NiO promotes the dissociation of water molecules, while Ni3N facilitates the generation and release of hydrogen molecules. The functional differentiation between these two materials at the interface drives the hydrogen spillover effect, synergistically accelerating the reaction rates of the basic steps in the HER. Through electrochemical testing, it is found that Ni3N/NiO/NF exhibits excellent HER performance in 1.0 M KOH solution, requiring only 58 and 98 mV overpotentials to achieve current densities of 10 and 100 mA cm-2, respectively, with a low Tafel slope of 42 mV dec-1. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) analyses confirm the enhanced capability of this heterostructure in hydrogen adsorption and desorption. Ultraviolet photoelectron spectroscopy (UPS) and X-ray photoelectron spectroscopy (XPS) tests reveal electron rearrangement at the interface, verifying the existence of hydrogen spillover pathways. Additionally, the superhydrophilic-superaerophobic wetting characteristics of the catalyst surface help improve the diffusion rate of reactants and the desorption efficiency of products, thereby further enhancing the overall catalytic stability.

Biomass‐derived chars offer a sustainable platform for electrocatalytic CO 2 reduction (ECO2R) when functionalized with nontoxic metals and heteroatoms. In this work, Cu, S, and N‐doped biochar were synthesized via pyrolysis of waste pine needles with addition of copper acetate and thiourea, providing a green, low‐cost, and scalable route. Three catalysts with varying Cu loadings were prepared, and electrodes were fabricated by drop‐casting the doped biochar with poly(2,6‐dimethyl‐1,4‐phenylene oxide) pentyl trimethylammonium ionomer (PPO‐LC) on carbon paper. Structural characterization by Raman spectroscopy revealed a balance between defect density and sp 2 domain size, while X‐ray photoelectron spectroscopy confirmed the presence of Cu + , nitrogen in aminic/pyridinic positions, and thioether‐type sulfur, key functionalities for CO 2 adsorption and activation. Scanning electron microscopy imaging showed a homogeneous, porous catalyst layer, facilitating gas transport and electron transfer. Electrochemical testing demonstrated that the catalyst with an intermediate Cu loading (3.1 at%) and copper(I) as active site achieves the highest selectivity toward acetate, surpassing the performance of catalysts with lower or higher Cu loading. The results highlight that careful tuning of Cu content and oxidation state, combined with heteroatom doping and controlled structural defects, is essential for designing efficient, selective, and durable biomass‐derived ECO2R electrocatalysts.

To address the challenge of controlling Fe impurity content during the recycling of aluminum alloys, this study utilized commercial 5083 aluminum alloy as a matrix to prepare alloy samples with four different Fe contents via smelting. The effects of Fe content on the microstructure, mechanical properties, and corrosion resistance of the as-cast 5083 aluminum alloy were systematically investigated. The results indicate that increasing the Fe content induces a significant morphological evolution of the Fe-rich phases, transitioning from compact Chinese-script α-Al(Fe,Mn)Si phases at low Fe levels to coarse needle-like β-AlFeSi phases. Concurrently, both the quantity and size of the second phases increase significantly. Mechanical testing reveals that the hardness of the alloy gradually rises from 67 HV to 72 HV due to second-phase strengthening. The tensile strength shows a trend of initially increasing and then decreasing, peaking at 0.45 wt.% Fe; however, excessive Fe leads to the formation of needle-like phases that cause stress concentration, resulting in a decline in tensile strength. The elongation decreases gradually with increasing Fe content, with a maximum reduction of 19.7%. Electrochemical tests show that higher Fe content increases the self-corrosion current density and decreases the capacitive loop radius, indicating a significant degradation in the alloy’s corrosion resistance. This work provides an experimental basis for the tolerance control of Fe impurities and the performance optimization of recycled 5083 aluminum alloys.

The marine environment is recognized as one of the most aggressive natural conditions affecting the long-term performance of concrete structures. High concentrations of chloride and sulfate ions in seawater, continuous moisture exposure, fluctuating temperatures, and mechanical loading collectively contribute to the degradation of concrete. These factors weaken the internal structure of the material, increase porosity, accelerate ion migration, and progressively damage the passive protective layer of steel reinforcement. As a result, corrosion develops more rapidly, leading to cracking, expansion of corrosion products, and a gradual loss of load-bearing capacity—posing a significant threat to marine infrastructure. This study synthesizes the findings of various researchers to identify and evaluate the modern laboratory, field, and analytical methods used to assess the durability of concrete in marine environments. Techniques such as electron microscopy for microstructural analysis, chloride diffusion tests for determining ion transport, permeability and porosity measurements for evaluating material density, and electrochemical methods for monitoring corrosion risk are examined. Field investigations complement laboratory observations, confirming that the splash zone is the most critical region where corrosion progresses at an accelerated rate. The results demonstrate that improving the durability of concrete in aggressive marine environments requires an integrated engineering approach rather than reliance on any single protective measure. Enhancing resistance to chloride ingress, optimizing concrete cover thickness, increasing impermeability, and employing corrosion-resistant reinforcement and advanced protective coatings are essential strategies. The combination of experimental data with analytical modeling further enables accurate prediction of service life and supports the development of reliable and long-lasting marine engineering structures. Overall, a comprehensive understanding of concrete behavior under marine exposure forms a solid foundation for designing durable, safe, and efficient coastal and offshore infrastructure. Keywords: Concrete, marine environment, corrosion, chloride diffusion, sulfate attack, microstructure analysis, water permeability, electrochemical testing.

Two-electron water oxidation reaction (2e- WOR) mediated by (bi)carbonate (CO3 2-/HCO3 -) is promising for anodic H2O2 production. However, previous H2O2 yields are usually unsatisfactory due to low local CO3 2-/HCO3 - concentration at the solid/liquid interface. These sluggish reaction rates mainly result from the restricted ion diffusion, and the obstacle of by-product O2 bubbles. To resolve this puzzle, a three-phase WOR system based on CO2 (g)/dual-catalyst composite (s)/KOH (l) is adopted. At the three-phase interface, a high local concentration of CO3 2-/HCO3 - can form in the CO2 adsorption unit and transfer to the WOR catalyst unit via the CO3 2-/HCO3 --mediated spillover effect. As a result, the largest H2O2 yield of 51.62mM at 50mA cm-2 was realized, superior to that of the conventional two-phase system. Density functional theory (DFT) calculations, electrochemical and CO2 adsorption tests, and in situ Fourier transform infrared spectra (FTIR) results jointly confirmed the larger adsorption amount of CO3 2-/HCO3 - ions, the spillover of CO3 2-/HCO3 - and their transformation to HCO4 -, and the whole reaction processes from CO2 adsorption to final H2O2 production at the three-phase interface. This is the first application of the three-phase design in WOR, which can provide guidance for efficient H2O2 synthesis in 2e- WORs and can also be applied in other electrochemical WORs.

Direct borohydride fuel cells (DBFCs) are promising for high-energy-density power sources, but their practical application is limited by slow borohydride oxidation reaction (BOR) kinetics, competing hydrogen evolution reaction (HER), and insufficient catalyst durability. In this work, a succulent-like hierarchical Ni/NiCo catalytic electrode has been reported, which was prepared by a two-step constant-current deposition through combining electronic modulation strategy and structural engineering. In situ attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), COMSOL simulations, and electrochemistry testing demonstrate that Co incorporation induces tensile lattice strain and modulates the electronic structure of a Ni-based catalyst, while the hierarchical architecture with defect-rich features maximizes active site exposure, accelerates mass transport, and suppresses the oxidation of nickel and the competitive HER, thus enhancing the direct borohydride oxidation. Consequently, the Ni/NiCo electrode delivers outstanding catalytic activity, stability, and selectivity to BOR. Moreover, when used as the anode, DBFC can achieve an open-circuit voltage of 1.91 V and a peak power density of 413 mW cm-2 and operate stably for 36 h under 50 mA·cm-2 at room temperature. This work establishes a cost-effective route for the development of next-generation high-performance DBFC anode catalysts and also enriches preliminary understanding about the electronic regulation and hierarchical architecture of catalysts.

High-entropy amorphous materials are attracting increasing attention due to their excellent corrosion resistance and radiation tolerance in nuclear environments. In this study, novel Al2Cr16Fe50V20Ti12 high-entropy alloy (HEA) coatings with thicknesses of 900 nm and 1400 nm were synthesized via magnetron sputtering and systematically evaluated for their structural, electrochemical, and mechanical performance. X-ray diffraction confirmed the amorphous nature of the coatings, while scanning electron microscopy revealed a denser, defect-free, and more uniform morphology in the thicker coating. Electrochemical testing in a 3.5 wt.% NaCl solution demonstrated a tenfold reduction in corrosion current density and nearly a twofold increase in charge transfer resistance for the 1400 nm coating, attributed to its improved passive film stability. Finite element modeling validated the experimental load-displacement behavior and revealed well-confined and uniformly distributed stress and strain fields within the coating. These findings establish the 1400 nm Al2Cr16Fe50V20Ti12 coating as a promising candidate for protective applications in chloride-rich and radiation-intense nuclear systems.

Ti6Al4V‐extra‐low interstitial (ELI) is favored for biomedical applications but is restricted by low wear and corrosion resistance. To overcome these limitations, oxide‐based surface modifications can be applied to improve the mechanical and electrochemical properties. In this study, Al, Zn, and Zr oxide coatings, as well as their Ag‐doped counterparts, were produced on Ti6Al4V ELI alloys fabricated by laser powder bed fusion additive manufacturing (LPBF‐AM) using the successive ionic layer adsorption and reaction (SILAR) method. The structural and morphological features of the coatings were analyzed by X‐ray diffraction (XRD), SEM, and a 3D profilometer, while Vickers hardness measurements were also performed. Tribological properties were examined using a pin‐on‐disk tester, and corrosion behavior was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) in artificial saliva fluid. The results demonstrated that the Ag‐doped Zr coating exhibited the superior overall performance, reducing the wear rate to 0.37 × 10 −5 mm 3 /Nm compared to 3.5 × 10 −5 mm 3 /Nm for the untreated alloy. Furthermore, electrochemical tests revealed that Ag doping significantly enhanced corrosion resistance, with the Ag–Zr coating achieving a protection efficiency of approximately 86% and reducing the corrosion current density to 4.4 from 32.6 μA·cm −2 observed in the untreated substrate.

This study presents the synthesis and ball-milling modification of titanite (CaTiSiO5) powders to enhance the thermal stability and performance of polypropylene (PP) separators for lithium-ion batteries (LIBs). CaTiSiO5 was synthesized using a ceramic route, and the experimental design varied the milling cycles and sphere sizes. Characterization techniques, including scanning electron microscopy, X-ray diffraction, Fourier-transform infra-red spectroscopy, surface area analysis, thermal analysis, and electrochemical tests, confirmed the production of high-purity monoclinic CaTiSiO5. Ball milling effectively reduced the particle and crystallite sizes while increasing the specific surface area, total pore volume, double-layer capacitance, and ionic conductivity, while also reducing the cell resistance. Coating PP separators with the modified CaTiSiO5 significantly improved their thermal stability and enhanced their electrochemical properties, including the electron transfer rate and Coulombic efficiency. These findings demonstrate the potential of ball-milled CaTiSiO5 as a valuable material for developing safer and more efficient LIBs.

This paper demonstrates the potential use of affordable, and efficient electrocatalysts, which can maintain the efficiency and stability of platinum-group metals in water-splitting. The study focuses on the optimization and setup of a PEM electrolyzer, alongside the development of new methods for preparing membrane electrode assemblies (MEA) using cost-effective and efficient catalyst materials. The integration of a fibrous membrane layer into the MEA architecture represents a promising design strategy, offering excellent structural and transport properties. Herein, a simple preparation method for modified NiCoP electrocatalysts in the form of carbon fibers is presented, using needleless electrospinning combined with airbrush spraying of an Ir-black solution onto a perfluorosulfonic membrane (Nafion), later pressed together with NiCoP carbon fibers to form a custom-made MEA. For electrochemical testing, custom made MEA was directly evaluated in the PEM electrolyzer setup, providing a preliminary demonstration of overall performance and stability.

Abstract The growing demand for efficient energy storage systems in applications such as electric vehicles, smart grids, and portable electronics has intensified interest in high-performance lithium–metal batteries. Conventional fabrication routes for porous copper current collectors (CCs) face limitations in achieving complex architectures and reliable mechanical stability. In this work, stereolithography-based 3D printing combined with pressureless sintering is employed for the rapid fabrication of copper CCs. For the first time, porous copper CCs are fabricated using this approach, delivering controlled architectures with enhanced structural robustness and electrochemical functionality. Optimization of sintering parameters, including sintering temperature, heating rate, and holding time, was carried out using Response Surface Methodology based on a Box–Behnken design, followed by multi-objective genetic algorithm analysis in MATLAB. The optimized conditions significantly improved relative density, compressive yield strength, and volumetric shrinkage, while minimizing experimental effort. The fabricated porous copper CC exhibited superior mechanical strength under compression, withstanding ~ 35 MPa at 60% strain, ensuring integrity during coin cell assembly and cycling. Electrochemical testing demonstrated a stable and high Coulombic efficiency of approximately 95 percent over 100 cycles, significantly outperforming conventional copper foil. The porous structure effectively facilitated uniform lithium deposition, mitigated dendrite growth, and accommodated volume fluctuations. This research offers a scalable route to fabricate durable, high-performance CCs, advancing next-generation electrochemical systems with stable, high-surface-area electrodes. Graphical Abstract

In order to address the rapid degradation of biomedical magnesium alloy implants in corrosive media, this study employed a surface modification approach. After fluorination pretreatment of AZ31 magnesium alloy, a silicon (Si) thin film was uniformly deposited on the surface using magnetron sputtering, aiming to enhance the corrosion resistance and biocompatibility of the AZ31 alloy. The corrosion behavior of both coated and uncoated samples in simulated body fluid (SBF) was evaluated through electrochemical tests. Additionally, cytotoxicity and hemocompatibility were assessed using CCK-8 and hemolysis assays, respectively. The results indicate that, compared with the bare magnesium alloy substrate and the magnesium alloy coated with a single sputtered Si thin film, the Si thin film deposited on the fluorinated magnesium alloy substrate exhibits a lower corrosion current density, as well as higher charge transfer resistance, phase angle, and impedance modulus. In addition, the fluorinated Si-coated sample shows lower cytotoxicity. These findings indicate that the combination of fluorination pretreatment and magnetron-sputtered Si thin films is an effective approach for enhancing the early stage corrosion resistance and initial biocompatibility of AZ31 magnesium alloys, providing a promising surface engineering strategy for further investigation.

Abstract The commercial viability of anion exchange membrane (AEM) electrolysis requires optimization of various stack components, with specific catalyst-ionomer combinations often yielding higher current densities, lowered Tafel slopes, and improved mass activity. In this joint theoretical-experimental study, theoretical calculations detail the impact of Versogen’s piperidinium functional group on the complex, kinetically limiting oxygen evolution reaction, finding that the functional group can act as a promoter of specific steps (O*/O 2 * formation; H 2 O/O 2 desorption with reaction enthalpies ranging between 0.2–0.6 eV at higher coverages of O x H y intermediates) on NiO and NiFeO x catalysts. In particular, Fe sites on the NiFeO x catalyst facilitate concerted mechanisms of O*/O 2 * formation and H 2 O desorption with a low enthalpy of 0.5 eV; O 2 desorption alone requires only 0.3 eV. In contrast, Versogen-IrO 2 results in stronger Ir–O bonds, where the enthalpies for bond breaking (Ir–OH 2 and Ir–O 2 ) are considerably higher (1.4 eV and 1.6 eV, respectively). Rotating disk electrode studies utilized commercially available NiO and IrO 2 and synthesized 7.5 wt % Fe in NiFeO x catalysts in combination with Versogen, a common AEM ionomer, and Nafion, an alternative binder. Electrochemical testing validated the impact of these mechanistic changes on ionomer-catalyst combinations, finding that Versogen particularly activates NiO and NiFeO x compared to IrO 2 . Following a 13.5 h hold at 1.8 V, mass activities and Tafel slopes improved to 34 ± 13 A g −1 and 79 ± 2 mV dec −1 (NiO) and 82 ± 4.9 A g −1 and 72 ± 2 mV dec −1 (NiFeO x ). In contrast, Versogen-IrO 2 only reached 17 ± 2.9 A g −1 and 81 ± 3 mV dec −1 . Optimization of the ionomer-catalyst can yield significant increases in performance from initial activity and after an electrochemical conditioning procedure: this enhancement to the mass activity resulted in a 200.9 ± 106.1% improvement for Versogen-NiFeO x and 1284.2 ± 260.5% for Versogen-NiO. In contrast, Nafion-NiFeO x and -NiO offered moderate improvements of 39.1 ± 30.5% and 120.9 ± 59.1%, respectively.

Inhibition of microbiologically influenced corrosion in 90/10 CuNi alloy by a novel antibacterial peptide.

Electrochemical testing and comparison of supercapacitator prototypes derived from soot and treated with N,N-dimethylformamide and perchloroethylene

3D porous cellulose/polyaniline aerogel composite as a high-performance electrode for selective electrosorption of rhenium.

Vacancy-engineered 1T-MoS2/MnS heterostructures on graphene ribbons enabling high-energy, long-cycle Lithium-ion batteries.