Graphene and nanotubes are examples of carbon nanomaterials that are highly conductive, possess high surface area and adjustable porosity thus can make charge discharge, high power density and long life cycle a reality in supercapacitors. However, low energy density, structural degradation, and voltage-induced interfacial instability arising from electrolyte decomposition, carbon corrosion, and interfacial degradation remain key obstacles to practical implementation. Structural and surface properties of chemistry are linked to the electrochemical behavior and the approaches to enhance the charge storage, rate performance, and the reduction of failure mechanisms are categorized in this review. MOF-based ultrathin carbons and 3D lattice's structure hierarchy is beneficial because it decreases the transport distances between ions in thick electrodes, increasing areal measures. The doping of hetero atoms, in particular, nitrogen, regulates electronic structure and quantum capacitance, providing nitrogen with an excellent instrument in raising higher double-layer storage. A representative example is provided by MnO 2 /carbon nanostructures, in which conductive carbon skeletons are hybridized with pseudocapacitive components to optimize the trade-off between energy density, power output, and cycling stability. Devices of high volume and flexible are produced using printing and roll-to-roll processing in high-speed rate. The application of biomass-based carbons and low-tortuosity scaffoldings are also applauded as the future of multifunctional, long-term, supercapacitors and commercial applications. Distinct from prior reviews, this work emphasizes design-driven synthesis by systematically benchmarking carbon nanomaterial strategies across material classes, device architectures, voltage windows, mass loadings, and electrolytes to extract practical structure–performance guidelines. This review systematically discusses material design principles, synthesis strategies, structure–property relationships, and electrochemical performance metrics, followed by current challenges and future research directions. • Comprehensive review of carbon nanomaterials (0D–3D) for high-performance supercapacitors. • Correlates hierarchical pore design and heteroatom doping with improved energy and power density. • Discusses mechanism-aware stability and interfacial protection strategies for long cycle life.

FeCl3/KOH two steps activated biocarbon with hierarchical porosity and oxygen-rich for enhanced supercapacitor applications

Environmental concerns have driven widespread research into energy storage for new energy development. Despite Bi0.5Na0.5TiO3-based ceramics offer high power density, fast charging/discharging, and good temperature stability, a major challenge of low energy density resulting from low breakdown strength and polarization hysteresis, limits their practical use despite other advantageous properties. In this work, a novel core-multi-shells structure, coupling the anti-ferroelectrics core, relaxor ferroelectrics inner shell, and linear dielectrics outer shell together, is constructed. This core-multi-shells structure induces multilevel lattice distortions, which facilitate quick polarization responses and effectively hinder the formation of long-range polar order, thus delays polarization saturation and weakens hysteresis. Beneficial from this heterogeneous polarization configuration, a remarkable discharge energy storage density of 11.05 J/cm3 at 790kV/cm is achieved, together with good temperature stability and frequency stability, demonstrating the great application potential of this design.

Strategic microenvironment engineering of single-atom catalysts offers a method for simultaneously enhancing oxygen reduction reaction (ORR) activity and stability. Herein, we synthesize Fe single atoms on an S-doped hollow carbon matrix with carbon vacancies (Fe SAs/NSCV) via a topological transformation strategy. The resulting Fe SAs/NSCV exhibits exceptional ORR performance and enables aqueous zinc-air batteries (ZABs) with remarkably highpower density. In situ spectroscopic analyses confirm that S heteroatoms in the second coordination shell of FeN4 sites, along with adjacent carbon vacancies, collectively accelerate the conversion of oxygenated intermediates and simultaneously stabilize the FeN4 active site configuration of Fe SAs/NSCV. Theoretical calculations further reveal that introduced S species and adjacent carbon vacancies cooperatively fine-tune the hybridization of Fe 3dz 2 and O 2p orbitals, increasing the occupancy of antibonding orbitals near the Fermi level and thereby promoting *OH desorption. Meanwhile, this heteroatom-defect synergy strengthens the anchoring of Fe sites within the carbon matrix and enhances the thermodynamic stability of these sites, indicating robust resistance to demetallation under operating conditions. Overall, this work establishes atomic-level heteroatom-defect cooperation as an effective strategy for the concurrent optimization of activity and stability in multi-electron electrocatalysis.

Exploiting cost-effective trifunctional electrocatalysts toward oxygen evolution reaction, hydrogen evolution reaction and oxygen reduction reaction is important for sustainable energy conversion and storage devices yet challenging. Here, we report a single-phase trifunctional electrocatalyst Sr2CoRuO6-δ with well-defined super-exchange double perovskite structure, which can efficiently catalyze oxygen evolution, hydrogen evolution and oxygen reduction under alkaline conditions. As an air electrode, Sr2CoRuO6-δ delivers high peak power density of 216 mW cm-2, high specific capacity of 748 mAh g-1 and long lifespan up to 1000 h for liquid rechargeable zinc-air batteries, as well as broad temperature and deformation adaptability for solid-state flexible zinc-air batteries. Furthermore, an anion exchange membrane water electrolyzer employing Sr2CoRuO6-δ as both cathode and anode requires a cell voltage of 1.90 V at the current density of 1 A cm-2 and shows a stable and rapid response when coupled with fluctuating solar electricity. Combining complementary in-situ and microscopic techniques, spatiotemporal surface reconstruction behavior of Sr2CoRuO6-δ under varied reactions is comprehensively investigated and true active components are identified.

Nickel-zinc (Ni-Zn) batteries have high-power densities and unrivalled potential for cost-effectiveness and sustainability. However, reliability concern quickly arises from their delicately balanced operational window, characterized by significantly different reduction and oxidation mechanisms at the electrode-electrolyte interfaces. Accurately identifying and utilizing the ideal faradaic reactions, while avoiding degradative side reactions, is key to them reaching their full market potential. Here we show that by continually monitoring the real-time strain and temperature evolution of commercial Ni-Zn batteries during cycling with fiber Bragg grating (FBG) sensors, critical insights can be gained. Utilizing systematic cycling with varying charge cutoff voltages, specifically between 1.85V and 1.90V, we track volumetric deformation and temperature changes at the cell level with signature indications of charge storage mechanisms. Evidence shows that while applied voltages of 1.88V during cell charging initially appear unremarkable, repeated cycling with this voltage gives rise to nonreversible reactions. This contrasts sharply voltages of 1.875V were found to safely avoid such mechanisms, indicative of the anticipated operational mode and cell capacity. The demonstrated monitoring strategy offers a multidimensional, scalable sensing framework for Ni-Zn batteries and next generation battery management systems and suggest potential for integration with more intelligent or AI powered prognostics.

Widespread extracellular electron transfer pathways at the interface of bimetallic metal-organic frameworks composite bioanode.

Single-atom Fe─N─C catalysts are promising alternatives to Pt-based catalysts for the oxygen reduction reaction (ORR), yet their performance is often limited by insufficient electronic modulation of the isolated Fe─N4 sites. Herein, we develop a facile chemical vapor deposition approach to synthesize a Fe─N─C catalyst (denoted as FF/Fe─NC) that simultaneously incorporates surface-accessible Fe/Fe2O3 nanoparticles (∼1.0nm) and atomically dispersed Fe─N4 sites. In alkaline media, FF/Fe─NC delivers a superior 4-electron ORR activity with a half-wave potential of 0.92V (vs. RHE) and a high turnover frequency (1.8 s-1 at 0.9V), significantly outperforming Fe/Fe2O3-free sample (Fe─NC) and commercial Pt/C. When employed as a cathode in a zinc-air battery, FF/Fe─NC delivers a high peak power density (218mW cm-2) and outstanding cycling stability. The enhanced performance is primarily attributed to the long-range electronic metal-support interaction (LR-EMSI) between Fe/Fe2O3 nanoparticles and Fe─N4 sites, which effectively optimizes the adsorption of reaction intermediates and accelerates the overall ORR kinetics. This work provides an effective design strategy for boosting the performance of metal and nitrogen co-doped carbon catalysts through the rational integration of metal nanoparticles and single-atom sites.

Antimony-based anodes have emerged as up-and-coming alloy-type anode materials for sodium-ion batteries (SIBs), owing to their high theoretical capacity and excellent electrical conductivity. However, they still suffer from severe issues such as substantial volume expansion during the sodiation-desodiation process. The novel antimony phosphate/carbon composites are designed through a multi-composited strategy in this work. The exceptional electrochemical performance of the synthesized phosphate/carbon composites arises from the synergistic combination of the unique physicochemical properties of antimony phosphate, the structural flexibility and high electrical conductivity of graphene oxide (GO), and the advantageous features of melamine-resin-derived nitrogen-doped porous carbon. For instance, the SbPO4@MFC/rGO-0.6 still maintains a high reversible discharge capacity of 201.6 mAh g-1, after 2000 cycles at a high current density of 2.0 A g-1. Density functional theory (DFT) calculations demonstrate that the optimized electronic structure of SbPO4@MFC/rGO enhances the interfacial interactions between antimony phosphate and the nitrogen-doped carbon matrix, thereby increasing the binding ability of the matrix with Na+. Furthermore, the SbPO4@MFC/rGO-0.6//Na3V2(PO4)3 full cell can manifest a high energy density of 168.2Wh kg-1. In particular, SbPO4@MFC/rGO-0.6//Na3V2(PO4)3 delivers an energy density of 103.2Wh kg-1 while maintaining the high power density of 794.1W kg-1.

ABSTRACT As electronic devices rapidly evolve toward higher power density and integration, the importance of efficient thermal management grows significantly. In the context of nano-reinforced thermoplastic composites, establishing effective thermal path through the filler network is crucial. In this study, by optimizing the ratios of two sizes of hexagonal boron nitride (h-BN) nanosheets in the poly (ether ether ketone) (PEEK) matrix, a significant enhancement of the thermal conductivity of PEEK/h-BN composites was achieved. The thermal conductivity of a PEEK/h-BN composite containing a 3:7 weight ratio of the two sizes of h-BN(with 15 wt% overall h-BN content) achieved the highest thermal conductivity of 0.87 W/m·K due to the formation of more complete thermal paths. Additionally, based on the structural distribution of boron nitride nanosheets (BNNSs) observed in scanning electron microscopy (SEM), the influence of heat transfer direction along single-layer BNNSs, as well as the interlayer relative displacement and torsional angle of bilayer BNNSs, on the thermal conductivity of BNNSs/PEEK composites was investigated through molecular dynamics simulations. The results show that when heat flow is transmitted along the armchair direction of BNNSs, the BNNSs/PEEK composites exhibit higher thermal conductivity. Furthermore, by regulating the microstructure of BNNSs, the interface scattering in BNNSs/PEEK composites can be effectively reduced, and the interfacial coupling of BNNSs/PEEK composites can be improved, leading to an enhancement in thermal conductivity. This study provides experimental data and theoretical support for the further development of high-performance thermal management materials.

Seawater-based zinc-air batteries (SWZABs) offer a compelling pathway for energy supply in marine environments due to their high theoretical energy density and abundant electrolyte resources. Their practical deployment, however, is fundamentally limited by chloride-induced corrosion, catalyst poisoning, and sluggish oxygen reduction/evolution reaction (ORR/OER) kinetics at air cathodes. Here, we report a heterostructured catalyst consisting of WC-Co nanoparticles interfaced with atomically dispersed Co sites on N-doped carbon (CoNP/WC@CoNC), which delivers bifunctional oxygen electrocatalysis under seawater conditions. In situ electrochemical characterization and computational calculations reveal that WC with spatially extended W 5d orbitals acts as an interfacial electronic modulator that downshifts the Co d-band center through W 5d-Co 3d hybridization, accelerating *OH desorption and *OOH conversion steps in ORR and OER, respectively. Simultaneously, this W 5d-Co 3d coupling effect suppresses chloride-triggered corrosion and thus ensures robust stability. Accordingly, CoNP/WC@CoNC exhibits a small ORR/OER potential gap of 0.68 V, and the derived SWZAB achieves a high peak power density (233.4 mW cm-2) and superior lifespan (>2500 h). This work provides insights into using 5d transition-metal carbides as an interfacial electronic modulator for designing durable and highly active bifunctional catalysts for seawater-compatible energy devices.

Electrochemical conversion of nitrate waste into ammonia represents a promising route for closing the anthropogenic nitrogen cycle, yet its efficiency is severely hampered by the sluggish supply of dilute nitrate and the parasitic hydrogen evolution derived from overwhelming interfacial water. Herein, we exploit the potential-driven structural transformation of amphiphilic surfactant assembly from disordered gauche conformations to ordered all-trans conformations to construct a dynamic permselective gate at the reaction interface. In situ spectroscopic investigations reveal that this field-induced reorientation enables the cationic headgroups adjoining the active surface to proactively enrich nitrate species via electrostatic attraction, while the distal long hydrophobic alkyl chains form a densely packed barrier that effectively shields the electrode surface from bulk water to suppress hydrogen evolution. With this tailored microenvironment, the enriched nitrate concentration and regulated proton supply work in synergy to match the reactant availability with the proton-electron transfer, significantly accelerating the reaction kinetics. As a result, the optimized system achieves a remarkable ammonia yield of 295.78 mg h-1 mg-1 and a near-unity Faradaic efficiency of 99.61%. Furthermore, an aqueous Zn-NO3- battery assembled with this cathode delivers a high power density of 37.42 mW cm-2 and simultaneous ammonia production, providing a promising paradigm for energy-efficient nitrogen looping.

Thermoelectric generators (TEGs) can harvest waste heat for small electronics. However, printed planar TEGs are often limited by low thermocouple density within a given footprint. Here, we present a paper-based rolled thermoelectric generator (Rolled TEG) that autonomously transforms from a planar sheet into a cylindrical geometry via paper self-folding using a fully printed fabrication process. Silver nanoparticle ink is inkjet printed to form electrodes and interconnects, while PEDOT:PSS is screen printed to form p-type thermoelectric legs, enabling series-connected architectures on paper substrates. The self-folding transformation rearranges thermocouples onto the inner cylindrical surface, increasing thermocouple density per projected installation area while preserving leg length and electrical connectivity. By systematically examining printing conditions and electrode pattern design, we clarify how internal resistance and output characteristics are governed and demonstrate that the rolled geometry enhances footprint-normalized power generation by achieving a footprint-normalized power density of 18.9nW cm-2, which is 28.1 times higher than that of the Planar TEG. This work establishes autonomous paper self-folding as an effective design strategy for compact, fully printed thermoelectric devices.

As urgent demands increase in energy-grid systems, supercapacitors have been further documented as highly promising energy-storage technologies across a range of applications owing to their high-power density, rapid charge-discharge capabilities, and prolonged endurance life. Porous carbon-based materials, particularly those derived from metal-organic frameworks (MOFs), are prominent candidates for supercapacitor electrode materials owing to their customizable inner-pore structures and superior electrochemical properties. In this work, we systematically manipulate the carbonization temperature (700-900 °C) of Al-NDC-MOF to tailor the hierarchical pore structure, defect density, and surface chemistry of the resulting porous carbons (AC-Al-NDC-x), aiming to unravel the structure-performance-device correlations required for stable dual-ion storage. Systematic characterization reveals that carbonization temperature plays a crucial role in regulating pore structure hierarchy, defect density, and surface functional groups. As a result, the optimized sample (AC-Al-NDC-800) exhibits balanced electrochemical performance, enabling its application as both positive and negative electrodes in symmetric and asymmetric two-electrode devices. This behavior is attributed to the synergistic effect of micropores for charge storage, mesopores for ion transport, and appropriate surface functionalities for interfacial stability. Although the achieved energy density and cycling stability are comparable to previously reported porous carbon systems, this work highlights a rational design strategy for balancing pore structure and surface chemistry to achieve stable dual-ion storage under practical two-electrode conditions.

Achieving spontaneous dipole alignment without external poling remains a grand challenge in developing high-performance ferroelectric nanogenerators. This work reports a self-poling mechanism driven by engineered interfacial fields at the polymer-ceramic junction. By embedding lead-free Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) crystals into a P(VDF-TrFE) matrix, we create strong localized electric fields that promote unidirectional dipole orientation, thereby eliminating the need for conventional electrical poling procedures. The resulting hybrid piezo-triboelectric nanogenerator (H-PTENG), optimized at a 1 wt% BCZT loading, exhibits remarkable energy-harvesting performance with a high open-circuit voltage (∼173.4 V), short-circuit current (∼5.23 µA), and power density (∼182 µW cm-2), outperforming most lead-free counterparts. This dielectric percolation-like optimum maximizes the dielectric-ferroelectric coupling mediated by Maxwell-Wagner-Sillars interfacial polarization, simultaneously enhancing piezoelectric and triboelectric outputs while preserving low dielectric loss. The device also demonstrates robust mechanical durability (>10 000 bending cycles) and retains usable output under varying humidity and temperature conditions, although its performance is reduced at ultra-high relative humidity due to water-induced charge dissipation. Its real-world applicability is confirmed by directly powering commercial electronics, including 82 LEDs, a digital wristwatch, an electronic scoreboard, and a Bluetooth-enabled humidity-temperature sensor. Collectively, this work establishes a scalable, lead-free, and poling-free design paradigm based on interfacial field engineering for next-generation flexible, self-powered electronic systems.

A gadolinium hydroxide-MXene nanocomposite was synthesized through a microwave-assisted route as a supercapacitor electrode material. The prepared electrode material demonstrated a specific capacity of 128 mAh g-1, along with 98% capacitance retention after 5000 cycles. An solid-state hybrid supercapacitor (Gd-MX//AC) delivered an energy density of 25.8 Wh kg-1 and a high power density of 3000 W kg-1, while maintaining outstanding capacitance retention over repeated cycles.

Methanol oxidation is vital for direct methanol fuel cells (DMFCs) and energy-saving H2 production by replacing the sluggish oxygen evolution reaction, but it suffers from CO poisoning, CO2 emission, and high overpotential issues. Herein, we present the simultaneous formation of a monodispersed intermetallic PtBi core/tensile-strained PtNiBi shell (I-PtBi@TS-PtNiBi) via a one-pot wet chemical method, to facilitate a self-powered methanol upgrading and H2 production system without CO2 emission. This I-PtBi@TS-PtNiBi electrocatalyst exhibits a high mass activity of 33.2 A mg-1 Pt toward methanol oxidation and produces value-added formate with high Faradaic efficiencies over a wide potential window of 0.6 to 1.2 V. This enables a high DMFC peak power density of 175.0 mW cm-2 to drive efficient H2 production in an anion-exchange-membrane water electrolyzer at low cell voltages (1.16 V@2.0 A cm-2), producing formate in both the DMFC and electrolyzer. This work offers insights into the rational design and synthesis of sophisticated multimetallic electrocatalysts for efficient energy conversion and chemical upgraders.

Simultaneously achieving high power density and longevity in cost-effective proton-exchange membrane fuel cells (PEMFCs) is imperative for their commercialization, yet it poses a significant challenge to the fuel cell catalyst, particularly under light-duty vehicle (LDV) or heavy-duty vehicle (HDV) conditions. Here, we present a versatile phosphorus (P)-driven strategy to enhance the activity and durability of platinum-manganese (Pt3Mn) alloys, in which P acts as a pivotal bridging element between Pt3Mn nanoparticles and the carbon support as well as an activator for Pt3Mn surfaces. Importantly, goblet-like P-Pt3Mn enables outstanding peak power densities of 4.11 W cm-2 in H2/O2 and 2.05 W cm-2 in H2/air under HDV condition, as verified by a third-party platform and stack-level validation. Meanwhile, P-Pt3Mn exhibits an exceptional accelerated stress test (AST) stability for 30 000 cycles (2.1% mass activity decline), significantly exceeding the U.S. Department of Energy (DOE) target. For commercial visibility, we demonstrate that the P-Pt3Mn-based fuel cell can be operated stably at a high current density of 3.0 A cm-2 beyond 1000 h. Detailed mechanistic and theoretical investigations reveal the excellent performance of P-Pt3Mn from the surface enrichment of P on Pt3Mn alloys and the formation of interfacial Pt-P-C coordination, which effectively promotes *OH desorption and mass transport as well as inhibits nanoparticle agglomeration. These groundbreaking results firmly establish P-Pt3Mn as the most efficient and durable fuel cell catalyst for practical PEMFC applications in urban transportation.

ABSTRACT Shape memory alloys (SMAs) are attractive for soft robotic actuation because of their compactness and high power density, yet their widespread application is limited by slow thermal recovery. Here, we introduce ionic wind cooling as a compact thermal‐management strategy to overcome this bottleneck and improve the cyclic actuation performance of SMA‐driven soft robotic systems. Two ionic wind configurations were designed and comparatively evaluated for localized cooling of SMA springs. Both significantly accelerated SMA recovery with only minimal additional power input, and the needle–ring configuration was selected for subsequent integration because of its favorable stability and compact geometry. By coupling SMA springs with an origami‐based compression–twisting mechanism, an actuator‐level soft twisting module capable of reversible bidirectional rotation exceeding 80° was developed. The cooling strategy was further extended to multiple SMA‐driven modules and a reconfigurable soft robotic arm capable of coordinated twisting, bending, and multimodal grasping. The results show that ionic wind cooling not only enhances the recovery of individual SMA actuators but also enables faster motion switching and improved cyclic response at the system level. This work demonstrates ionic wind cooling as a compact and effective strategy for enhancing the dynamic performance of SMA‐driven soft robotic systems.

Owing to advancements in implantable bioelectronic devices, there has been an increase in demand for biocompatible energy sources with long-term electrochemical and mechanical stability. In this study, we present the fabrication of a flexible asymmetric supercapacitor (MXene//AC) based on two-dimensional Ti3C2Tx MXene nanosheets. The supercapacitor demonstrates excellent electrochemical performance with an areal capacitance of 66.43 mF cm-2, energy density of 13.2 Wh kg-1, and a high power density of 2300 W kg-1. The supercapacitor retained 95% capacitance after 5000 charge-discharge cycles and displayed negligible performance degradation under various bending angles, highlighting its mechanical suitability for wearable electronics. Density functional theory (DFT) analysis revealed that the metallic Ti-C backbone of Ti3C2Tx MXene and its O/F terminations work synergistically to enable rapid electron transport and reversible proton-coupled surface redox, supporting predominantly surface-controlled charge storage with a significant pseudocapacitive contribution. To complement device-level studies, we assessed the in vivo safety profile and antioxidant potential of Ti3C2Tx MXene nanosheets in Sprague-Dawley (SD) rats through acute dermal, subchronic oral, and subchronic intraperitoneal toxicity evaluations. Acute dermal exposure up to 100 mg kg-1 caused mild skin responses without necrosis, while subchronic administration for 28 days revealed no considerable abnormalities in biochemical parameters (alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, creatinine), inflammatory markers (IL-1β, IL-6), or oxidative stress biomarkers (malondialdehyde, glutathione). Histopathological evaluations confirmed the absence of structural damage or inflammation in vital organs. Additionally, MXene nanosheets demonstrated antioxidant activity by scavenging 2,2-azino-bis(3-ethyl)benzothiazoline-6-sulfonic acid free radicals in a dose-dependent manner, highlighting their potential to reduce oxidative stress in biomedical applications. Overall, this dual-focused study demonstrates that MXene nanosheets are not only highly effective for developing flexible, stable asymmetric supercapacitors but also exhibit favorable in vivo biocompatibility and antioxidant properties at the tested doses. These findings emphasize the potential of MXene-based materials as next-generation, fully biocompatible energy storage devices for advanced implantable bioelectronic systems.