Search Results (570)

The growing demand for efficient and sustainable energy storage systems has intensified research on advanced materials for lithium–ion batteries (LIBs). Gel-based synthesis routes—particularly polymeric and chelating gel techniques—have emerged as powerful methods for designing lithium–ion battery (LIB) anode materials with tailored microstructures, composition uniformity, and enhanced electrochemical performance. These methods facilitate the transformation of solution-phase precursors into homogeneous and finely structured materials, enabling precise tuning of physicochemical properties. This review provides a comprehensive overview of the fundamental principles of polymeric and chelate gel synthesis routes, highlighting their ability in controlling particle size, morphology, and phase purity. Their applicability to a wide range of anode materials, including transition metal oxides and silicon-based composites, is discussed. The manuscript highlights LIBs anode material developments via gel precursor chemistry, structure–property relationships, and future directions toward scalable and sustainable electrode manufacturing. Full article

This study focuses on a group of scanning electrochemical probe microscopies used to reveal the early stages of galvanic coupling corrosion reactions, based on the use of microelectrochemical sensors for measuring local potentials and currents associated with chemical reactions occurring at anodic and cathodic sites, and their correlation with results obtained with conventional electrochemical techniques. Although galvanic corrosion between dissimilar metals is generally analyzed by assuming that the anodic and cathodic half-cell processes occur in different metals, the use of microelectrochemical techniques reveals that the corrosion process is actually more heterogeneous. Cathodic activity is present in both metals, but to very different degrees. Anodic activity is also localized, as the surface of the more reactive metal is not fully available to undergo anodic dissolution. Because galvanic corrosion processes are heterogeneously distributed over the surface of the coupled materials, even in model systems, the identification of cathodic sites and reactions is often insufficient when monitored by conventional electrochemical methods. These observations are particularly relevant when corrosion protection measures aim to minimize or eliminate the activity of cathodic reaction sites. Full article

Faced with a global energy crisis and ecological degradation, overall water splitting (OWS) is a pivotal approach for renewable energy conversion and storage. However, its industrial application is hindered by the high energy barriers/sluggish kinetics of the anodic oxygen evolution reaction (OER), as well as the scarcity of precious metal catalysts limiting large-scale deployment. Herein, a cobalt-based layered double hydroxide (Co-LDH) was used as the precursor, and a multi-strategy synergistic modification (hydrothermal synthesis, Fe doping, sulfurization, and external magnetic field magnetization) was applied to fabricate the Fe-Co₃S₄-MS-20 min electrocatalyst. This strategy establishes Fe-Co bimetallic synergistic active centers, and magnetic treatment modulates the electron configuration of Fe 3d orbitals without changing the material’s lattice spacing or morphology. Structural characterizations and electrochemical measurements were used to investigate the effects of combined modifications on the catalyst’s phase structure, morphology, electronic structure, and trifunctional catalytic performance toward the hydrogen evolution reaction (HER), OER, and urea oxidation reaction (UOR). The Fe-Co₃S₄-MS-20 min catalyst exhibits a larger electrochemical active surface area, lower charge transfer resistance, and smaller Tafel slope in 1 M KOH, it achieves overpotentials of 165 mV for HER (10 mA·cm⁻²) and 310 mV for OER (100 mA·cm⁻²), along with superior UOR performance and long-term stability. In situ impedance and Raman spectroscopy confirm that magnetization accelerates charge transfer and promotes in situ reconstruction. Synergistic multi-strategy regulation optimizes the electronic structure of active centers, reducing electrocatalytic energy barriers. This work provides new insights into designing high-performance non-precious metal electrocatalysts and offers experimental support for external magnetic field regulation in electrocatalyst modification. Full article

Since the first successful synthesis of borophene in 2015, this atomically thin boron allotrope has attracted extensive attention due to its polymorphic structures, metallic conductivity, and outstanding mechanical flexibility. As a new member of the two-dimensional (2D) materials family, borophene exhibits a unique triangular lattice with tunable hexagonal vacancies, leading to rich structural diversity and anisotropic physical properties. Recent breakthroughs in synthesis—particularly molecular beam epitaxy (MBE), chemical vapor deposition (CVD), and solvothermal-assisted liquid-phase exfoliation (S-LPE)—have significantly expanded the accessible structural phases and improved control over film quality and stability. Meanwhile, borophene’s distinctive combination of structural and electronic characteristics has enabled its rapid development in both energy and biomedical applications. In energy storage, borophene serves as a promising anode material for lithium/sodium-ion batteries and a lightweight medium for hydrogen storage and supercapacitors, owing to its metallic conductivity, high surface charge density, and large adsorption capacity. In biomedicine, borophene-based nanoplatforms exhibit excellent photothermal conversion efficiency, enabling multifunctional roles in cancer diagnosis and therapy. Despite these advances, several challenges—such as environmental instability, oxidation susceptibility, and limited scalable synthesis—continue to restrict practical implementation. Future progress will depend on chemical functionalization, surface passivation, and machine-learning-assisted materials design to achieve oxidation-resistant, large-area, and biocompatible borophene derivatives. This review summarizes recent advances in borophene synthesis, structural engineering, and multifunctional applications, while outlining key scientific challenges and future opportunities for the realization of borophene-based materials in next-generation energy and biomedical systems. Full article

Solid-state electrolytes (SSEs) are essential for achieving long-term stability and fast-charging performance in secondary batteries. Although Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) offers high ionic conductivity, its practical application is restricted by high-temperature sintering requirements and interfacial reduction at the lithium anode. In contrast, Li-based oxide electrolytes can be sintered below 600 °C, offering improved compatibility with conventional electrodes such as graphite and silicon. In this study, a Li₂O–LiCl–B₂O₃–Al₂O₃ (LCBA)/LATP composite SSE was fabricated via hot-press co-sintering at 600 °C. Composites with LCBA:LATP weight ratios of 8:2, 7:3, 6:4, 5:5, 3:7, and 2:8 were prepared to identify the optimal composition. The 3:7 composite achieved a sintered density of 2.40 g/cm³ and an ionic conductivity of 2.5 × 10⁻⁴ S/cm. Phase evolution and sintering behavior were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Compared to single-phase LCBA or LATP, the composite electrolyte exhibited improved interfacial stability and lower interfacial resistance against lithium metal. Full article

In recent years, silicon-based anodes have become a model of commercial success among various high-capacity electrode materials. They also offer a promising substitute for the lithium metal anode (LMA) in lithium–air batteries (LABs), which have the highest specific energy. However, the poor air stability of lithiated silicon-based anodes makes pre-lithiation considerably more difficult and costly in mass production to improve their initial Coulombic efficiency and cyclability, which complicates their material design and electrode manufacturing. To address this issue, intensified efforts have been devoted in recent years, mainly by constructing encapsulation structures, such as core–shell, pomegranate-like or peapod-like architectures. These designs have achieved significantly boosted stability in dry air and, in some cases, even under prolonged exposure to ambient humidity. On the other hand, it was found that silicon-based anodes often provide better cyclic stability than LMAs in LABs and lithium–oxygen batteries (LOBs); however, in most cases, the silicon-based anodes were not optimized for air stability. This review summarizes the relevant works on improving the air stability of silicon-based anodes and LABs/LOBs that used a silicon-based anode, intending to shed light on future development of air-stable silicon-based anodes and bridge the gap between the electrodes’ air-stability and their application in LABs/LOBs. Full article

The CNT-supported nanodispersed Pt–Mo catalysts for the ethanol electrooxidation reaction in the alkaline solution are synthesized and their characteristics are studied. Based on the XPS studies in a wide range of platinum content (10–40 wt %), it is found that in the composition of the catalysts, platinum is predominantly in the metallic state, and molybdenum is in the hexavalent form, probably in the form of MoO₃ oxide. According to the XRD and electrochemical studies, the Pt/CNT and PtMo/CNT catalysts with equal platinum contents (~20 wt %) are characterized by similar platinum crystallite sizes (5–10 nm) and electrochemically accessible surface areas (23–26 m²/g_Pt). This indicates that platinum is not shielded by the molybdenum compounds. When the platinum content increases above 20 wt %, the Pt:Mo atomic ratio increases (the nominal ratio is 1:1), which may be due to the decoration of molybdenum oxide with platinum nanoparticles. A study of the kinetics of the ethanol electrooxidation reaction showed that the activity of the PtMo/CNT system is higher than that of the Pt/CNT catalyst. However, the efficiency of platinum use decreases as its content in the PtMo/CNT system increases from 10 to 40 wt %. On the other hand, the systems containing 20–40 wt % Pt exhibit the highest activity per unit catalyst weight, making them very promising for use as a component of the anode active layer of a fuel cell. The tests of the alkaline ethanol fuel cell based on the synthesized catalysts show the maximum power density of 29 mW/cm², which corresponds to the level of the best literature parameters under similar experimental conditions. Full article

In nuclear power, marine engineering, and other fields, a matching system composed of duplex steel and copper alloy is a common combination for rotating components in a seawater environment. However, this system is susceptible to galvanic corrosion that seriously threatens its service safety and service life, with ZCuAl10Fe5Ni5 being the main component corroded. Additionally, current corrosion research on this system has evident gaps. Specifically, the influence of area ratio on galvanic corrosion remains insufficiently understood, and the action mechanism of Cl⁻ on the ZCuAl10Fe5Ni5-based corrosion product film in seawater, as well as the product evolution path, has not been fully revealed, which restricts the development of targeted protection technologies. This study explores the degradation mechanism of ZCuAl10Fe5Ni5 in a specific high-salinity environment (20,000 mg/L Cl⁻), characteristic of nuclear power plant service conditions. The results show that due to the significant electrode potential difference between the SAF2507 duplex steel and ZCuAl10Fe5Ni5 copper alloy, a stable galvanic couple is formed, with ZCuAl10Fe5Ni5 acting as the anode and undergoing dissolution corrosion. When the area ratio of ZCuAl10Fe5Ni5 (anode) to SAF2507 duplex steel (cathode) is 1:50, a significantly stronger galvanic effect is observed. The high concentration of Cl⁻ in seawater can damage the surface of the ZCuAl10Fe5Ni5-based corrosion product film, leading to intensified local corrosion. The ZCuAl10Fe5Ni5-derived corrosion products have a layered structure mainly comprising a mixed system of Cu-Al-Mg oxides/hydroxides, and the corrosion process is accompanied by selective aluminum depletion corrosion. This study provides insight into the corrosion mechanism and key influencing factors of ZCuAl10Fe5Ni5 in the matching system, as well as a theoretical basis and technical support for the design of compatibility metal materials in a seawater environment and the control of corrosion in ZCuAl10Fe5Ni5. Full article

Manganese-based cathodes offer high capacity, low cost, and safety for aqueous zinc-ion batteries (AZIBs), yet suffer from Mn dissolution, Jahn–Teller distortion, and sluggish Zn²⁺ kinetics. Herein, a Zn/Co co-doped MnO nanoporous carbon composite (denoted as ZnCo-MnO@NPC) derived from a bimetallic ZnCoMn metal–organic framework (ZnCoMn-MOF-74) is successfully synthesized and proposed as a high-performance cathode to address these challenges. The introduction of Zn²⁺ increases the initial specific capacity of MnO, while Co doping effectively suppresses the Jahn–Teller distortion and improves the integrity of the structure. Furthermore, the nanoporous carbon matrix facilitates electrolyte infiltration and accelerates ionic transport. To further suppress dendrite growth and enhance cycling stability, a zeolitic imidazolate framework (ZIF-8) protective layer is engineered on the zinc anode (denoted as ZIF-8@Zn), effectively mitigating dendrite formation. The ZnCo-MnO@NPC//ZIF-8@Zn full cell demonstrates superior electrochemical performance, delivering 281.3 mAh g⁻¹ at 0.1 A g⁻¹ and retaining 98.7% of this value after 3500 long-term cycles at 2.0 A g⁻¹, a remarkable finding that underscores its potential for high-performance energy storage. Collectively, this work highlights that transition metal ion doping represents an effective way to design efficient high-performance MOF-derived cathodes of AZIBs. Full article

In this study, a polyethylene glycol (PEG)-based solid electrolyte composite (PEG)₁₀LiClO₄/NaAlOSiO suitable for anodic bonding packaging was successfully fabricated via a combined ball milling and hot pressing process. The micromorphology, ion transport characteristics, and mechanical packaging properties of the composite were systematically investigated using characterization techniques including electrochemical impedance spectroscopy, X-ray diffraction, scanning electron microscopy, and anodic bonding performance tests. The results demonstrate that doping with NaAlOSiO molecular sieve can effectively reduce the crystallinity of the polymer matrix, construct more efficient carrier transport pathways, and simultaneously enhance the ionic conductivity and mechanical properties of the material. When the mass fraction of NaAlOSiO doping is 8 wt.%, the composite exhibits a room temperature ionic conductivity of up to 1.31 × 10⁻⁵ S·cm⁻¹. Under room temperature and a bonding voltage of 800 V, the sample with this doping ratio achieves the optimal anodic bonding with metallic Al, and the tensile strength of the bonding interface reaches 5.93 MPa, showing excellent application prospects in micro–nano-packaging. Full article

Sludge electro-dewatering has emerged as a research hotspot in advanced sludge treatment due to its ability to effectively remove interstitial water that is difficult to separate by mechanical dewatering. This paper systematically reviews the fundamental principles, key influencing factors, evolution of electrode materials, and engineering applications of electro-dewatering technology. Emphasis is placed on analyzing the effects of sludge properties, electric field parameters, and electrochemical reactions on dewatering efficiency. The characteristics and applicable scenarios of three generations of electrode materials—from conventional metal electrodes and carbon-based materials to dimensionally stable anodes (DSA)—are summarized. Current challenges include insufficient electrode stability, the trade-off between energy consumption and efficiency, limited understanding of underlying micro-scale mechanisms, and difficulties in process scale-up. Future efforts should focus on the development of high-performance electrode materials, investigation of multi-field coupling enhancement mechanisms, establishment of machine learning-based intelligent control strategies, and engineering design of continuous electro-dewatering equipment to promote its large-scale application in sludge treatment and disposal. Full article

This study reports that titanium nanoparticles can be used as a surface coating to enhance the corrosion resistance of 316 stainless steel. It specifically examines the influence of the deposition temperature (T_dep) on the coating’s structural and morphological properties, including corrosion behavior. TiO₂ nanoparticles were thoughtfully deposited on steel substrates at temperatures of 300, 400, and 500 °C using a horizontal hot-wall tubular reactor. This equipment was expertly engineered at the CIDETEQ laboratory through the metal–organic chemical vapor deposition (MOCVD) concept. Titanium isopropoxide [Ti(OC₃H₇)₄] was used as the precursor for the coating synthesis. Structural analysis was conducted using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM). Corrosion performance was evaluated under accelerated conditions in 0.5 M H₂SO₄ using potentiodynamic anodic polarization (AP), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The corrosion test indicates that increasing T_dep significantly differentiates the coating morphology and improves corrosion resistance. AP revealed that the pitting potential (E_pit) shifted to more positive values, ranging from +1.4 to +1.5 V. CV voltammograms indicated that coated samples had lower passive current densities (I_p ≈ 10⁴ to 10⁵ A/cm²) than the bare substrate. EIS analysis demonstrated that the coating deposited at 500 °C processed the most favorable electrochemical performance, resisting corrosion for over 28 days. This coating achieved the highest electrical resistance (297 kΩ·cm²) and the lowest capacitance (2.7 μF/cm²), attributed to the formation of a crystalline anatase phase composed of pyramidal-like nanoparticle agglomerates (~40 nm). The dense packing structure effectively blocks charge-transfer pathways, restricting electron and ion transfer. Finally, MOCVD-based chemical surface modification with TiO₂ nanoparticles is considered an innovative method to improve the corrosion resistance of stainless steel, thereby prolonging its durability under accelerated sulfuric acid exposure. Full article

Water electrolysis has emerged as a strategically appealing route for the sustainable production of green hydrogen (H₂) via the hydrogen evolution reaction (HER), though the sluggish kinetics of the oxygen evolution reaction (OER) remains a bottleneck hindering large-scale practical applications. In this regard, an attractive solution is offered by the integration of the ethanol oxidation reaction (EOR) into hybrid water-splitting systems, favorably reducing anodic overpotentials. Nonetheless, an open challenge is related to the fabrication of eco-friendly and economically viable catalysts free from noble metals, combining efficiency and stability. Herein, we explore nickel-oxide-based nanostructures grown onto porous Ni foam scaffolds by a scalable hydrothermal (HT) approach as EOR electrocatalysts. Material properties arising from modulation of the sole HT growth time are investigated by complementary structural, microscopic, and spectroscopic techniques. Electrochemical tests demonstrate good durability and very attractive EOR performances, mainly influenced by the morphology and the NiOOH surface content of the target systems. Overall, the present work advances an attractive route to transition-metal-based electrocatalysts for efficient alcohol-oxidation-assisted water electrolysis. Full article

Leaching carbon residue (LCR) is a carbonaceous solid waste generated during the hydrometallurgical recycling of spent lithium-ion batteries. Although its high graphite content offers substantial potential for resource recovery, the residual heavy metals and fluorides present in LCR pose considerable environmental risks. Currently, LCR has not garnered sufficient attention within the industry, and the lack of recycling technologies suitable for large-scale disposal results in resource wastage and environmental pollution. To address these challenges, this study proposes an innovative strategy based on the concept of multi-field synergistic enhancement. The proposed approach involves recovering and regenerating graphite (RG) from LCR via low-temperature molten salt roasting assisted by high-pressure and mechanical activation. A combination of advanced characterization techniques was employed to compare the physicochemical properties of RG and commercial graphite (CG) and to systematically evaluate the technical feasibility of using regenerated graphite as an anode material for lithium-ion batteries. The results demonstrate that, under optimized molten salt roasting and aqueous leaching conditions, the carbon content of RG reaches 99.94 wt%, indicating the efficient removal of non-carbon impurities from the graphite matrix. Compared to CG, RG retains a typical layered structure; however, a lower carbon content (99.94 wt%) and poorer structural order (I_D/I_G = 0.30) are observed. In terms of electrochemical performance, RG delivers a discharge specific capacity of 394.64 mAh/g during the first cycle and exhibits excellent cycling stability, with a capacity retention of 86.50% after 100 cycles. This electrochemical performance is comparable to that of commercial graphite. The proposed multi-field-assisted low-temperature molten salt roasting technique enables the efficient recovery of high-value graphite resources from LCR, establishing a full-lifecycle recycling strategy tailored for lithium-ion battery applications. Full article

To address the application requirements of energy storage devices for new energy electric vehicles—including high energy density, high-power density, fast charging and discharging, and long-term cycling stability—traditional symmetric supercapacitors are often limited by low energy density and poor compatibility between the anode and cathode, making it difficult to meet the high-efficiency energy storage demands under the dynamic operating conditions of electric vehicles. This study focuses on the regulation of hierarchical thin-film structures and the innovative heterogeneous coating interface engineering with precise slurry coating and film-forming optimization and designs and fabricates NiCo₂O₄/NiFeO composite thin-film electrodes and Mn-doped porous carbon (Mn-PC) thin-film electrodes. The uniform, compact and stable coating formation on nickel foam substrates via controllable slurry coating facilitates the efficient integration of active materials and conductive supports. The electrode slurries were coated onto conductive nickel foam substrates, and high-performance aqueous supercapacitors were assembled using an asymmetric configuration. A systematic study was conducted covering material preparation, structural characterization, electrochemical testing, and full-device performance evaluation. Using techniques such as XRD, XPS, SEM, TEM, BET, and an electrochemical workstation, the study revealed the structure–activity relationships among material morphology, crystalline phases, pore structure, and electrochemical performance, elucidating the charge storage mechanisms of the composite electrode films and the principles of synergistic adaptation between the anode and cathode. The results indicate that NiCo₂O₄ nanowires decorated with in situ-grown NiFeO nanosheets to form a composite structure; when coated onto nickel foam, this forms a uniform, porous electrode film with a specific surface area of 171.3 m²/g, a specific capacitance as high as 1746 F/g at 1 A/g, and a capacity retention rate of 94.0% after 10,000 cycles. After coating and film formation, the Mn-PC anode introduced pseudocapacitive active sites through uniform Mn doping, resulting in a film electrode specific capacitance of 348 F/g and significantly improved rate and cycling performance. The assembled NiCo₂O₄/NiFeO//Mn-PC asymmetric supercapacitor exhibits a thin-film electrode specific capacitance of 153 F/g at 1 A/g, with a maximum energy density of 52 Wh/kg. Even at a power density of 9000 W/kg, it maintains 45 Wh/kg, and retains 89.5% of its capacity after 10,000 cycles, with overall performance outperforming most previously reported transition metal-based devices. This coating-engineered electrode fabrication strategy breaks through the interface mismatch and structural instability bottlenecks of traditional thin-film electrodes, providing a novel material system and an efficient coating assembly strategy for high-performance supercapacitor thin-film electrodes in new energy electric vehicles, and offers experimental evidence and technical references for the development and application of high-power energy storage coating devices for automotive use, as well as the innovative design of electrode coating engineering in energy storage fields. Full article