Conventional graphite anodes struggle to meet high-energy-density demands, while silicon faces challenges from ∼400% volume expansion. In this study, two nitrogen (N) and phosphorus (P) co-doped polymer precursors (MSD and ADP) were synthesized via a one-pot method, and commercial poly(diphenoxyphosphazene) (PDP) was selected as a carbon source. Three porous carbon materials (C-MSD, C-ADP, C-PDP) were prepared by high-temperature pyrolysis. The effects of N,P doping ratios and polymer structures on the microstructure and electrochemical performance were systematically investigated. Furthermore, core-shell structured silicon/carbon composites (Si20C80-MSD, Si20C80-ADP, Si20C80-PDP) were constructed by high-energy ball milling with nano‑silicon. The results show that C-ADP, which possesses a self-crosslinked structure, exhibits the largest specific surface area (rich in micro/mesopores), the highest defect density, and an interlayer spacing (0.367 nm) larger than that of graphite (0.335 nm), facilitating rapid Li+ insertion/extraction. After 800 cycles at a current density of 1 A g−1, C-ADP retains a reversible specific capacity of 337.3 mAh g−1 with an average Coulombic efficiency exceeding 99% and a capacity retention of 78.7%, significantly outperforming C-MSD and C-PDP. Among the silicon/carbon composites, Si20C80-ADP exhibits a denser coating morphology and better silicon dispersion owing to the self-crosslinked structure of the ADP-derived carbon layer, maintaining a specific capacity of 567 mAh g−1 after 200 cycles. This study demonstrates that rational design of the molecular structure of polymer precursors and N,P doping strategies can effectively tune the microstructure and interfacial properties of pyrolytic carbon, providing a new approach for the development of high-performance silicon-based anode materials.

A full-cell with a 3DP NNMMWO cathode and 3DP hard carbon anode achieves 125.9 mA h g −1 at 0.1C and retains 77.3 mA h g −1 at 1C over 100 cycles.

Silicon anodes are attractive candidates for high energy density lithium-ion batteries owing to the low working potential, high theoretical capacity, safety and abundance of Si. However, its commercialization is mired by various challenges such as low electrical conductivity, slow electro-chemical kinetics, huge volume expansion and unfavorable solid electrolyte interphase formation induced electro-chemical performance deterioration. Among various strategies attempted to mitigate these issues, pre-lithiation of anode materials is well-established but, it still involves the dependability on less abundant, expensive and low safety Li based source material. In this regard, pre-magnesiation of Si-based anodes would be effective and economic owing to the fascinating properties of Mg and its compatibility with Si. Additionally, Mg is highly active and can easily form thermally and mechanically stable Mg2Si like intermetallic compound with refined grains on reaction with Si. This review provides an insightful discussion on the research progress of pre-magnesiation agents and examines the pre-magnesiation strategies that help in controlling the volume expansion, SEI growth and mechanical pulverization of Si based anodes. It explores the primary mechanisms and strategies related to pre-magnesiation process with a focus on improving the ion transport and initial coloumbic efficiency in Si based anodes. Furthermore, it highlights the effect of composition, particle morphology, nano structuring, electrolyte additives and choice of polymers that affect the interfacial stability, electrochemical and cycling performance of Si based anodes. This review also discusses the critical challenges and future perspectives of pre-magnesiation in Si-based anodes thus promoting their application towards next generation batteries.

ABSTRACT Bismuth selenide (BiSe) is an n ‐type thermoelectrics with promising room‐temperature potential as a tellurium‐free alternative to Bi 2 Te 3 ‐based materials. It features ultralow lattice thermal conductivity ( κ lat ), but suffers from excessively high carrier concentration, yielding a low Seebeck coefficient. This remains a fundamental challenge in BiSe. Here, we introduce yttrium (Y) doping in Sb‐alloyed BiSe (Bi 0.7 Sb 0.3 Se), inducing substantial Bi vacancies to reduce carrier concentration. Experimental characterization combined with theoretical calculations demonstrates that Y preferentially substitutes Bi at the Bi 2 bilayer sites, which opens the bandgap and flattens the valence/conduction bands, thereby enhancing the band‐edge density of states (DOS) effective mass and increasing the Seebeck coefficient. This enhances power factor across a broad temperature range. Defect regulation and multiscale nanopores further amplify phonon scattering, reducing κ lat by 50% at 393 K. Consequently, Bi 0.64 Sb 0.3 Y 0.06 Se achieves a peak zT of 0.91 at 393 K and average zT of 0.76 (300 – 523 K), representing significant progress within the emerging BiSe‐based material. Furthermore, an 8‐pair BiSe‐based module achieves a conversion efficiency of 4.6% and a normalized power density of 10.8 µWcm −2 K −2 , which is expected to pave the way for BiSe‐based materials to become a realistic n ‐type thermoelectric material for sustainable applications.

Organic cathode materials represent promising candidates for lithium metal batteries, boasting advantages such as structural tunability, sustainability, and high theoretical capacity. Although phenothiazine (PTZ) has demonstrated excellent performance as a high-voltage p-type redox-active cathode, previous research has primarily focused on its polymeric forms, with the substituent effects in small molecules remaining underexplored. This work investigates three PTZ derivatives functionalized with different substituents to elucidate the structure-property relationship. Among them, the sulfonate-modified PTZ exhibits promising properties, including a high discharge plateau (3.5 V vs. Li/Li+), minimal dissolution in electrolytes, and ultralong cycling stability (78.3% capacity retention after 10,000 cycles at 3 A & centerdot;g(-1)). This molecular engineering strategy provides key insights for designing durable organic cathodes for high-energy lithium metal batteries.

Water hyacinth leaves (WHL) are an inexpensive renewable fuel resource that can be employed for energy creation through hydrolysis of simple fermentable reducing sugars. In this work, a hybrid microwave irradiation (MWI)–ternary deep eutectic solvent (TNDES) system involving choline chloride (ChCl) as a hydrogen bond acceptor (HBA), triethanolamine (TEOA) as an amine-based hydrogen bond donor (HBD), monoethylene glycol (MEG), diethylene glycol (DEG), or triethylene glycol (TEG) as polyol-based HBD components was employed as an efficient and green material for pretreatment of WHL for further transformation of the polysaccharide portion. The results showed that hybrid MWI/TNDES (ChCl-TEOA-MEG, ChCl-TEOA-DEG, and ChCl-TEOA-TEG) pretreatments were very efficient for lignin removal from WHL, with efficacy ranging from 80.4 ± 3.2 to 87.7 ± 3.8% compared with pretreatment using hybrid MWI/binary NDES (ChCl-TEOA) (75.6 ± 2.4%). The higher efficacy of the hybrid MWI/TNDES pretreatment was attributed to the impacts of MWI on extracting biological materials and the lower viscosity, higher pH, and lower density associated with the TNDESs. The results indicate that WHL pretreated using hybrid MWI and ChCl-TEOA-MEG, ChCl-TEOA-DEG, and ChCl-TEOA-TEG resulted in significantly boosting cellulose digestibility (4–5 times that of pristine WHL and 1.5 times that of hybrid MWI/ChCl-TEOA-treated WHL). The effect of MWI/TNDES pretreatment was confirmed by scanning electron microscope (SEM) pictures, and lignin and hemicellulose elimination were clearly observed in Fourier transform infrared (FTIR) spectra. The lignin-rich material separated by the hybrid MWI/TNDES pretreatment was analyzed using thermogravimetric analysis (TGA) to obtain the thermal behaviors of this hybrid, pretreated WHL material. In our experimentation with hybrid MWI/TNDES, under optimum circumstances of MWI time of 6 min, MWI power of 300 W, and a temperature of 90 °C, 43–49 g/L TRS yield was achieved by acid-catalyzed hydrolysis employing WHL substrate after being optimized by the single-factor experiments (SFE) approach, while the optimized TRS for untreated WHL and hybrid MWI/binary ChCl-TEOA were estimated to be 12 g/L and 32 g/L, respectively. The hybrid MWI/ChCl-TEOA-TEG pretreated WHL resulted in a high ethanol yield (ca. 22.3 g/L) by Saccharomyces cerevisiae after 72 h of fermentation. This work demonstrates the potential of WHL as a sustainable bioenergy feedstock for bioethanol production in industrial biorefineries. The research establishes effective and green solvent pre-treatment materials and methods (based on hybrid MWI/TNDES) for the efficient removal of lignin and hemicellulose from WHL and cellulose recovery. In general, the research contributes to the development of environmentally friendly and cost-effective hybrid MWI/TNDES processes for WHL biomass conversion and offers strong evidence that hybrid MWI/TNDES processes represent a high-potential method for managing WHL infestations while generating useful products. Future studies should further investigate ways to enhance the efficacy of acid-catalyzed hydrolysis processes and assess the scalability of the technology for industrial applications.

Multi-hybrid energy storage systems (MHESS) have been deployed in urban railways recently to recover braking energy and stabilize voltage fluctuations in traction networks. To improve energy-saving efficiency, voltage stability, and prolong MHESS lifespan, an improved Multi-Agent Deep Reinforcement Learning (MADRL) framework for MHESS coordination was proposed. It treats real-time power allocation among MHESS as a sequential decision problem, incorporating state-of-charge (SOC) consistency into the reward function. To boost MADRL efficiency and policy generalization under time-varying operating conditions, a BH-MATD3 algorithm was developed to train the playback buffer in MADRL, which combines a MATD3 policy gradient with behavioral cloning and prioritized hindsight experience replay. Ablation studies show faster convergence and better performance. Moreover, to avoid SOC imbalance arising from purely learning-based policies, a SOC consistency current loop was designed, adjusting charging and discharging currents in real time, and acting as a safety-aware layer alongside the DRL policy. The proposed strategy was validated in MATLAB/Simulink. The simulation results demonstrate that it outperforms MAF, MATD3, MAPPO, and MADDPG algorithms in energy efficiency, voltage stabilization, and adaptability to emergency scenarios. On this basis, RT-LAB hardware in the loop (HIL) experiments was conducted, and the results further confirm the real-time feasibility and comprehensive performance of the proposed strategy.

Commercial polyolefin (PE) separators are incompatible with high-energy lithium metal batteries (LMBs) with high-nickel cathodes, owing to their poor electrolyte wettability, low desolvation efficiency, and severe polarization. Herein, a sulfonated-lithiated melamine-formaldehyde (MFSO) nanospheres functionalized PE separator (MFSO@PE) is developed. The MFSO@PE separator has excellent wettability for the electrolyte; the triazine rings, amine groups, and sulfonic acid groups () in the MFSO act as effective Li+-affinitive sites. A synergistic regulation mechanism was revealed: the outer facilitates Li+ desolvation, while the inner N-rich framework provides weak coordination to lower desolvation energy. Furthermore, the effectively repels anions, alleviating concentration polarization and increasing the Li+ transference number. Consequently, the composite separator enables Li||Li symmetric cells to operate stably for 2000 h. In Li||NCM811 cells, the MFSO@PE separator achieved 800 stable cycles at 3 C with a low-capacity decay rate of 0.031% per cycle, while high-loading graphite||NCM811 cells maintain 80% capacity (137.2 mAh g-1) after 1000 cycles at 1 C. Moreover, the MFSO@PE separator effectively captures Ni, Co, and Mn ions and prevents them from migrating to the anode. This work presents a dominant Li+ conduction and desolvation regulation nanosphere-based coating strategy for high-rate, long-life high-nickel batteries.

Magnesium (Mg)- based alloys and their composites have recently gained significant interest in the biomedical field as potential biodegradable materials due to their unique mechanical properties, bioresorbability, biocompatibility, and biological activity. Nevertheless, the widespread biomedical applications of Mg-based alloys and composites are still limited mostly by their superior corrosion rates and subsequent loss in mechanical integrity. In recent years, numerous research studies have been conducted to develop biodegradable Mg-based alloys and magnesium-based metal matrix composites (Mg/MMCs) with enhanced corrosion resistance and mechanical properties. In this paper, an effort has been made to discuss the various methodologies for processing biodegradable Mg/MMCs for important clinical applications. The major processing technologies for biodegradable Mg/MMCs, including liquid-state processing (e.g., stir casting), solid-state processing (e.g., powder metallurgy (PM)), in-situ processing, and modern additive manufacturing (e.g., powder bed fusion (PBF), selective laser melting (SLM), and wire arc additive manufacturing (WAAM)), are first briefly introduced. Subsequently, biodegradable Mg-based alloying designs and the current trend in biodegradable Mg-based alloys, including Mg/Ca, Mg/Zn, Mg/Cu, Mg/Sr, and Mg/RE, essential for biomedical applications, are reviewed in detail. This review article also comprehensively discusses the design of reinforcement materials for producing biodegradable Mg/MMCs for clinical applications. The current trends on biodegradable Mg/MMCs, including calcium phosphate (CaP)-based bioceramics, Si-containing bioceramics, biodegradable magnesium oxide (MgO), and carbon materials reinforced Mg/MMCs, are discussed. Special emphasis has been placed on the production techniques and various behaviors (e.g., mechanical properties, microstructure, biocompatibility, and corrosion behaviors) displayed by micro/nano-sized particles reinforced Mg/MMCs. The potential engineering applications of Mg/MMCs are also introduced. Ultimately, this review highlights the prospects of biodegradable Mg-based alloys and Mg/MMCs biomaterials in various biomedical applications. This review will serve as a valuable reference for young researchers and industry personnel with a comprehensive understanding of biodegradable Mg/MMCs utilized in biomedical applications.

Fluidic EGaIn confined in nanoporous SiOC forms a multiscale framework with dual-continuous electron/ion pathways and stress buffering. This self-adaptive design suppresses Si-anode pulverization, enabling high-rate performance and stable cycling.

The lithium polysulfides (LiPSs) shuttle effect and sluggish sulfur redox kinetics hinder the cycling stability and sulfur utilization of lithium‑sulfur (Li-S) batteries. Herein, a dual-defect engineering strategy is proposed to tailor the electronic state of sulfur electrocatalysts. This is exemplified by synthesizing a dual-defect electrocatalyst of oxygen-deficient manganese-doped Fe3O4 and carbon nanotubes (MndFe3O4-x@CNTs) via a one-step hydrothermal route. Theoretical analyses reveal the dual defects synergistically optimize the electronic structure of Fe₃O₄ by modulating its spin state. This leads to an upshift of the d-band center, strengthening the d-p orbital hybridization with LiPSs and significantly accelerating the bidirectional conversion kinetics. The interconnected mesoporous framework acts as a multifunctional host, offering ample space for sulfur loading and working synergistically with the catalytic centers to concentrate LiPSs for efficient conversion. Consequently, the composite cathode exhibits excellent performance, including a low capacity fading rate of 0.07 % per cycle over 500 cycles at 1C, a high-rate capacity of 892.1 mAh g-1 at 3C, and an initial capacity of 582.7 mAh g-1 at 0.2C under a high sulfur loading of 9.1 mg cm-2. This work establishes a paradigm for developing high-performance Li-S batteries through precise defect engineering of mesoporous transition metal oxides.

Waste heat harvesting with thermoelectric generators (TEGs) is fundamentally limited by low conversion efficiency and operational instability, particularly under conditions of fluctuating external temperatures. Here, we propose a novel sandwich-style TEG to achieve high-efficiency waste heat harvesting and conversion. The design is based on a phase change material-integrated thermoelectric generator (PCM-TEG), fabricated by sandwiching TEG modules between two layers of PCMs. This architecture transforms passive thermal storage into active energy conversion, thereby unifying efficient heat management with continuous power generation. The synergistic design addresses long-standing challenges including poor energy conversion efficiency, thermal oxidation, and short discharge duration. By employing thermally conductive electrodes and composite PCMs, the system maintains high thermal storage capacity while enabling stable, long-term electricity output from otherwise wasted heat. Experiments reveal a >100% enhancement in effective power density and a fivefold improvement in output stability and device lifetime. These results establish the PCM-TEG as a promising platform for next-generation thermoelectric battery systems, offering scalable solutions for sustainable energy storage, waste-heat utilization, and thermal insulation technologies.

The photocatalytic hydrogen evolution (PHE) is a crucial technique for converting solar energy into green hydrogen. However, the PHE efficiency remains limited by metal-acid site spacing. In this study, we present a lattice-strain strategy to precisely control the distance between the metal and acid site by doping rare-earth Ho atoms onto a ZnIn2S4 nanosheet. Ho-doped ZnIn2S4 exhibits a hydrogen evolution rate of 1865.49 µmol g-1 h-1 under visible light, approximately 2.4 times that of the pure sample, with an apparent quantum efficiency of 14.7% at 420 nm. This performance is attributed to precise control of the distance between metal and acid sites via tensile strain induced by Ho, resulting in greatly improved charge-transfer capability and reduced energy barrier of the reaction. This work provides new insights into the design of highly efficient photocatalysts via strain engineering, revealing the role of the metal-acid site distance as a crucial structural parameter in the synergistic regulation of charge dynamics and the thermodynamics of hydrogen evolution.

Commercial graphite used in lithium-ion battery anodes has reached its theoretical capacity limit. Polymer-derived carbon, which offers numerous sites for lithium storage, has emerged as a promising alternative to meet the increasing demand for high-energy density batteries. In this study, we investigated polymer pyrolyzed carbon and nano-silicon composites prepared through three methods: liquid-phase mixing (SiC-L), ball mill blending (SiC-S), and further milling with graphite (SiCG). By optimizing the silicon-to-carbon ratio (1:9, 2:8, 3:7, and 4:6), core-shell structured composites Si20C80-L and Si20C80-S with an optimal 2:8 ratio were obtained. The Si20C80-S anode delivered a reversible capacity of 471 mAh g-1 after 200 cycles with a 56% expansion rate. Incorporation of flake graphite produced a hierarchical silicon-carbon-graphite composite (Si20C60G20), achieving 500 mAh g-1 after 200 cycles and reducing the expansion rate to 34%. The improved performance arises from carbon matrix confinement of silicon and an optimized conductive network that enhances structural integrity and lithium storage. This study provides a feasible route toward scalable fabrication of high-stability silicon-based anodes for next-generation lithium-ion batteries.

Separator coating modification is regarded as a facile and effective strategy to enhance lithium metal batteries (LMBs) performance. In this study, a polyethylene (PE) composite separator modified with benzoxazine resin (BZ) nanospheres (BZ@PE) is developed. Abundant surface amine sites on BZ provide excellent capture capability for hydrogen fluoride (HF) generated during electrolyte aging. Adsorption experiments and density functional theory (DFT) calculations confirm BZ achieves an HF adsorption capacity of 0.686 mg g−1 and a binding energy of −99.2 kJ mol−1 between secondary amine sites and HF. Distribution of relaxation times (DRT) analysis reveals BZ@PE cells exhibit lower initial solid electrolyte interphase impedance and slower growth in charge transfer and diffusion impedances during cycling. Consequently, Li||LFP coin cells using BZ@PE maintain 91.0% capacity retention after 1600 cycles at 1 C and 82.2% after 4500 cycles at 3 C. Li||LFP pouch cell demonstrate 97.1% capacity retention after 180 cycles. Benefiting from the intrinsic heat resistance of BZ, thermal safety evaluations indicate the onset of thermal runaway is delayed by 239 min compared to PE separators, and the internal short-circuit temperature increases by 10 °C, ensuring a milder thermal runaway process. This work presents the BZ@PE separator as an effective strategy to synergistically enhance electrochemical performance and thermal safety in LMBs.

Bismuth telluride (Bi₂Te₃)-based thermoelectrics (TEs) are the state-of-the-art materials for near-room-temperature applications, with growing demand in flexible and wearable energy devices. Scalable fabrication of high-performance thin films is therefore essential for advancing practical TE devices, especially for applications in wearable electronics. Among various processing routes, brush-coating approaches, such as tape casting and screen printing, have attracted attention due to their simplicity, low cost, and compatibility with large-area flexible substrates. This review summarizes recent progress in the slurry processed Bi₂Te₃ films, highlighting the critical roles of particle size, morphology, and binder design in achieving stable slurries and dense films with optimized transport properties. Post-treatments, including sintering, annealing, and hot pressing, are discussed for their effects on densification, defect regulation, and performance enhancement. Representative device demonstrations are reviewed, from large-area energy harvesting to small-scale wearable TE generators. Finally, we provide perspectives on future directions, including film performance optimization, scalable manufacturing strategies, structural and interfacial design, and long-term environmental stability. These insights aim to accelerate the development of low-cost, high-efficiency TE films for next-generation energy conversion and cooling technologies.

Currently, the primary focus in the field of lithium-ion batteries (LIBs) is on increasing energy density to meet consumer demand for longer-lasting electronic devices. Traditional intercalation compounds face challenges in mass production due to their limited theoretical specific capacity and the high cost of cobalt and nickel. Compared to intercalation cathode materials, conversion-type cathode materials (e.g., FeF2) offer advantages including high theoretical specific capacity, abundant resources, and environmental friendliness. Therefore, FeF2 is considered a highly promising conversion-type cathode material. However, FeF2 faces several challenges, including significant volume expansion, low intrinsic conductivity, and severe interfacial side reactions. To address these issues, researchers have adopted modification strategies such as nanostructuring, surface coating, and elemental doping to enhance the electrochemical performance of FeF2. This study employed high-energy ball milling to introduce a polyvinyl alcohol (PVA)-derived carbon coating onto the FeF2 surface, synthesizing FeF2@PVA-C composite materials. Results indicate that the PVA-C coating mitigates volume expansion during charge-discharge cycles, enhances material conductivity, and partially suppresses side reactions, thus improving overall electrochemical performance. The results demonstrate that the FeF2@PVA-C cathode exhibits enhanced electronic and ionic conductivity, delivering an initial discharge specific capacity of 470 mAh g−1 at 0.1C. After 70 cycles at 0.1C, it retains a reversible capacity of approximately 244.2 mAh g−1 with a capacity retention of 53%. Furthermore, a capacity retention of 30% is achieved after 200 cycles at 0.5C, which is superior to that of pristine FeF2, confirming that the PVA-C coating effectively improves the cycling stability of FeF2-based cathodes.

Lattice plainification provides an effective approach to enhance carrier transport and suppress bipolar conduction in Bi2Te3-based thermoelectrics. However, their narrow bandgap often triggers intrinsic carrier excitation at elevated temperatures, limiting energy conversion efficiency. In this work, Pb-doped p-type Bi0.5Sb1.5Te3 (PbxBST, x = 0-0.01) alloys are synthesized to exemplify the lattice plainification strategy, wherein Pb atoms occupy intrinsic Bi vacancies and homogenize the lattice. This targeted modification not only enhances carrier concentration and electrical conductivity but also reduces bipolar thermal conductivity by minimizing structural disorder. As a result, the optimized Pb0.009BST sample achieves a peak ZT of 1.38 at 400 K, similar to 75 K higher than the pristine sample, and an average ZT of 1.24 over 300-500 K-nearly twice that of undoped Bi0.5Sb1.5Te3. Furthermore, a flexible thermoelectric device assembled from Pb0.009BST and commercial n-type Bi2Te2.7Se0.3 exhibits noted performance, delivering a power density of 8.7 mW cm(-2) at Delta T = 50 K and a maximum cooling temperature difference of 60 K. These findings confirm that Pb doping effectively suppresses bipolar thermal excitation and broadens the peak-temperature window. This work offers a practical route toward high-efficiency, flexible BiSbTe-based thermoelectric devices for wearable energy applications.

Herein, three representative silicon-based anode materials, namely pure nano-silicon (Si), ball-milled silicon/carbon composite (BM Si/C), and chemical vapor deposition silicon/carbon composite (CVD Si@C), were systematically investigated for their application in all-solid-state lithium batteries. X-ray diffraction and Raman spectroscopy analyses confirmed that BM Si/C maintained the crystalline structure of silicon with a defect-rich carbon network, while CVD Si@C exhibited an amorphous silicon phase uniformly distributed within porous carbon frameworks with Si–C covalent bonding. The initial reversible capacities for Si, BM Si/C and CVD Si@C were 2810.4, 1230.1 and 1648.2 mAh g− 1, with Coulombic efficiencies of 65.97, 62.81 and 72.94