Potassium-ion batteries (PIBs) represent a compelling alternative to lithium-ion technologies, yet their deployment is hindered by the large ionic radius of K+, which imposes a formidable barrier to reversible and efficient ion storage in conventional anodes. Although organic electrode materials (OEMs) offer intrinsic sustainability, cost-effectiveness, and structural tunability, they often suffer from severe dissolution and sluggish kinetics. Here, we present polycyclic aromatic hydrocarbons (PAHs) as a new anode platform for PIBs, designed through a molecular jigsaw strategy for pi-electron delocalization engineering. Rational jigsaw screening guided by theoretical calculations, a cyclopentane jigsaw is embedded into naphthalene (N-PAH) to yield acenaphthylene (A-PAH), which enlarges pi-conjugation, elevates the LUMO energy level, and strengthens pi-K+ interactions. This modification suppresses dissolution and enables a three-electron transfer process based on the pi-K+ storage mechanism. As a result, the tailored A-PAH anode can deliver 367.2 mAh g-1 at 0.05 A g-1, along with outstanding rate capability (112.4 mAh g-1 at 5 A g-1), and remarkable long-term stability over 1200 cycles with an ultralow capacity decay of 0.012% per cycle. This work pioneers the application of PAHs as pi-cation-driven organic anodes for PIBs, laying a solid foundation for designing robust and fast-charging potassium storage materials.

Abstract Lithium metal batteries (LMBs) employing sulfurized polyacrylonitrile (SPAN) cathodes offer a compelling pathway toward high energy density, yet their practical application is strictly hindered by insufficient interfacial stability and ion-transport kinetics. While liquid electrolytes facilitate rapid kinetics, they suffer from severe safety risks and active species shuttling. Conversely, uniform gel or solid electrolytes often create a “kinetic bottleneck” at the cathode interface. Herein, we report a composite gradient polymer electrolyte (CGPE) that is engineered via a functionalized separator that spatially modulates the in-situ ring-opening polymerization (ROP) of 1,3-dioxolane (DOL). Raman spectroscopic mapping confirms a well-defined gradient architecture, in which a polymer-dense region at the separator side provides a physical barrier against polysulfide shuttling and dendrite penetration, while a solvent-rich, gel-like environment is preserved at the cathode interface to ensure conformal wetting and rapid desolvation. Consequently, the CGPE-based Li-SPAN cells demonstrate an exceptional rate capability, delivering a specific capacity of 139.9 mAh g –1 at an ultra-high rate of 10 C, while maintaining a capacity retention of 75.1% after 500 cycles at 2 C.

Two-dimensional (2D) layered transition metal dichalcogenide (TMD) materials are promising hosts for potassium-ion storage, as their unique interlayer structures can well accommodate large-sized K+. However, their inherent drawbacks, including poor electrical conductivity, easy self-aggregation, and severe volumetric strain after intensive potassiation, often lead to inferior rate performance and rapid capacity decay that hinder their practical application. To address these critical challenges, numerous structural design strategies have been developed, such as dimensional regulation, layer structure design, defect engineering, and heterogeneous composite construction. Nevertheless, a systematic summary linking microstructure optimization, potassium storage mechanisms, and structure-performance relationships is still lacking. This review aims to fill this gap by overviewing advances in TMD-based anodes, clarifying intrinsic potassium storage mechanisms (intercalation-conversion), and emphasizing structure-performance correlation for rational design. Furthermore, specific future research directions are proposed, including integrated interface engineering, optimized layer structure design, and construction of novel heterostructures. This review is anticipated to enhance the recognition of 2D layered TMD potassium storage and promote the advancement of potassium-ion battery technology.

Facing the challenges of energy and environment, photocatalytic water splitting technology has become one of the solutions. In this study, the structure, electronic properties and photocatalytic mechanism of ZnTe/PtS2 heterojunction were comprehensively studied by first-principles calculations. The ZnTe/PtS2 heterojunction exhibits a band gap of 1.89 eV, showing a Z-scheme charge transfer mechanism. The heterojunction has a wider light absorption range and can perform photocatalytic water splitting in the pH range of 0 ∼ 14, showing a hydrogen evolution efficiency of up to 17.18%. In addition, the application of −8% ∼ 8% biaxial strain can further regulate the band gap of ZnTe/PtS2 heterojunction and enhance its light absorption ability. Therefore, ZnTe/PtS2 heterojunction is a promising photocatalytic water splitting material.

Enhancing ion transport kinetics in thick and dense electrodes is essential for developing supercapacitors that simultaneously deliver high energy and power densities. Although interconnected microporous structures have been demonstrated to effectively enhance ion transport kinetics at the particle scale (< 10 μm), it remains a fundamental question whether such structure can promote ion transport kinetics in practical thick electrodes (> 100 μm). Herein, we prepare an interconnected microporous carbon that uniquely integrates ultrahigh specific surface area, high compaction density, exceptional electrical conductivity, and robust crushing strength. Importantly, we show that the intraparticle interconnected micropores provide effective ion-transport pathways throughout the entire thick and dense electrodes. Although inferior to conventional hierarchically porous carbons at low mass loadings, this interconnected microporous carbon demonstrates more favorable capacitive and kinetic performance under high mass loadings, highlighting its potential for practical applications. Under commercial mass loading, the electrode delivers outstanding gravimetric, volumetric, and areal capacitances (182 F g−1, 98 F cm−3, and 1.82 F cm−2 at 1 A g−1) in organic electrolyte, and retains 41% capacitance at 10 A g−1. This work establishes a new design paradigm for advanced carbon electrodes targeting practical high-energy and high-power energy storage.

The design of vdW heterostructures provides an effective approach to tailoring electronic and optical responses through interfacial band engineering. Here, we computationally investigate the ZrS₂/AlSe bilayer system using first-principles methods. The optimized structure exhibits an interlayer spacing of 3.29 Å and an indirect band gap of 0.85 eV, which is narrower than those of the isolated monolayers. A type-II band alignment is established, facilitating the spatial separation of photoexcited carriers. The electronic structure shows pronounced tunability under external stimuli: biaxial strain can induce a semiconductor–metal transition, while the external electric field transforms the band arrangement from type II to type I. Optically, the heterostructure displays enhanced absorption in the ultraviolet region compared to its constituents, with the absorption profile being broadly modulated by strain and field effects. These adaptable characteristics underscore the potential of the ZrS₂/AlSe heterostructure for use in tunable photodetectors, light-emitting devices, and flexible optoelectronics.

The impetus for reliable lithium batteries under extreme low-temperature (LT) conditions has revived interest in organic electrodes, yet their practical deployment is hindered by severe electrode dissolution and sluggish Li+ desolvation kinetics. Here, we uncover solvent concentration polarization between the electric double layer (EDL) and bulk electrolyte as a hitherto-overlooked but decisive degradation mechanism. This polarization reshapes the EDL into a solvent-rich domain, elevating the desolvation barrier and amplifying solvent-electrode interactions that exacerbate dissolution. Guided by this insight, we engineer a highly depolarized solvent that suppresses EDL solvent aggregation and restructures the solvation structure from being solvent-dominated to anion-enriched. The resulting electrolyte achieves an exceptional ionic conductivity of 0.51 mS cm-1 at -60 degrees C and a high Li+ transference number of 0.65, while fostering a robust, inorganic-rich electrode|electrolyte interphase that mitigates dissolution. Consequently, even at -60 degrees C, the Li & Vert;DSR (disodium rhodizonate) cell affords an outstanding capacity of 184.3 mAh g-1 and remarkable cycling stability over 2000 cycles with an ultralow decay rate of only 0.0057% per cycle. This strategy proves generalizable to other organic electrodes, establishing the combating of solvent concentration polarization as a guiding principle for ultrafast-cycling and long-life lithium batteries under extreme LT conditions.

Lithium-sulfur batteries (LSBs) have a high theoretical energy density (2600 mA hg-1), but problems such as low sulfur conductivity, the polysulfide shuttle effect, and slow Li2S oxidation kinetics have seriously affected their development. Based on the first-principles calculation framework, this study explores the anchoring ability and catalytic conversion mechanism of Janus configuration single-layer MSSe (M = Hf/Zr/V) when acting as a sulfur support for lithium-sulfur batteries. With the simulation calculation of structural stability, adsorption characteristics, conductivity, charge transfer, and Li2S oxidation reaction kinetics, it is confirmed that VSSe has outstanding characteristics as a potential sulfur carrier and can significantly inhibit the shuttle effect of soluble polysulfides. The VSSe monolayer maintains metallicity before and after the adsorption of LiPSs, ensuring continuous electronic conductivity. At the same time, the synergistic mechanism of the adsorption-catalytic process in MSSe (M = Hf/Zr/V) is revealed, providing new ideas for building a new sulfur support that has both outstanding anchoring efficiency and efficient catalytic transformation.

The ZrSSe/GaP van der Waals heterojunction is studied via first-principles calculations. The most stable configuration exhibits an indirect bandgap of 1.565 eV with type-II band alignment, forming a direct Z-scheme charge-transfer pathway. Phonon spectra and AIMD simulations confirm its stability. The GaP conduction band minimum provides Ue = 1.033 eV for the hydrogen evolution reaction (HER), reducing the barrier from 1.701 to 0.668 eV; the oxygen evolution reaction (OER) rate-limiting step (O* → OOH*) becomes downhill with an additional 2.293 V bias. A – 2% compressive strain induces an indirect-to-direct bandgap transition, while band edges remain suitable for water splitting across the −5% to +5% strain range. The heterojunction shows enhanced optical absorption (4.220 × 105 cm−1 in the visible) and achieves an exceptional solar-to‑hydrogen (STH) efficiency of 16.160%. These results highlight the ZrSSe/GaP heterojunction as a promising candidate for photocatalytic water splitting and optoelectronic devices, and provide design insights for Janus-based heterostructures.

The structural stress/strain induced by K-ion intercalation remains a critical challenge for K-ion batteries. To address this, a dopamine-intercalated WS2 hybrid (Dam-WS1.87) with a unique strain-self-relaxation architecture was fabricated. Interestingly, the WS2 matrix undergoes a structural transformation owing to the intense infiltration effect of dopamine molecules, expanding interlayer spacing (0.813 nm) and introducing 6.5% S-vacancies while preserving high compaction density (4.0874 g cm-3). The engineered structure demonstrates remarkable mechanical stability, exhibiting only 19.0% crystallite expansion upon full potassiation (vs. 101.3% for pristine WS2), demonstrating efficient strain alleviation through its strain-self-relaxation architecture. Asa result, Dam-WS1.87 delivers reversible capacities of 312.6 mA h g-1/1277.7 mA h cm-3 at 0.125 C, along with superior rate capability (maintaining 210.4 mA h g-1 at 5 C) and unprecedented cycling stability (85.3% capacity retention after 1400 cycles at 1 C). This work provides new insights into designing strain-tolerant electrode materials for next-generation energy storage systems. (c) 2025 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

To address the sluggish hydrogen oxidation reaction (HOR) kinetics in anion exchange membrane fuel cells (AEMFCs), a PtRuNiCoCu@NHCSs electrocatalyst is developed through the in situ synthesis of ultrasmall (<3 nm) PtRuNiCoCu high-entropy alloy nanoparticles (HEA NPs) confined within hollow mesoporous nitrogen-doped carbon spheres (NHCSs), using a vapor-infusion-assisted pyrolytic reduction strategy. The nanoreactor confinement provided by NHCSs suppresses phase separation, yielding a single-phase face-centered cubic structure, ensures uniform dispersion and stability of the HEA NPs. The ultrasmall nanoparticle size provides a large electrochemically active surface area and abundant accessible active sites. Electronic interactions among the multimetallic components create electron-rich and electron-deficient regions on the HEA surface, forming spatially separated dual-active sites for H* and OH*, which mitigates competitive adsorption and generates a broad distribution of adsorption energies. This establishes multiple low-energy reaction pathways, collectively lowering the HOR barrier, while simultaneously weakening CO binding. These synergistic structural and electronic effects endow the PtRuNiCoCu@NHCSs catalyst with outstanding alkaline HOR performance, achieving a mass activity of 3329.32 A g−1Pt+Ru and an exchange current density of 9.43 mA cm−2, along with remarkable durability and CO tolerance. This study provides both a general synthesis route for ultrasmall HEAs and a mechanistic framework for designing advanced AEMFC electrocatalysts.

Lithium-sulfur batteries are considered one of the most promising next-generation energy-storage systems. However, their practical applications are severely limited by the shuttle effect of soluble lithium polysulfides (LiPSs) and sluggish sulfur redox kinetics. In this work, density functional theory calculations were performed to systematically investigate Janus GeSSe, NiSSe, and ZrSTe monolayers as asymmetry-driven catalytic interfaces for lithium-sulfur batteries. The calculated results show that all Janus monolayers exhibit good structural stability and semiconducting behavior. More importantly, the intrinsic asymmetry of the Janus configuration induces interfacial polarization and surface-dependent charge redistribution, leading to distinct sulfur redox activities on the two opposite surfaces. Adsorption calculations reveal that the S-terminated surface exhibits stronger interactions with LiPSs, with optimal adsorption energies of -3.92, -3.81, and -2.38 eV for GeSSe, NiSSe, and ZrSTe, respectively. Free-energy analysis further demonstrates that GeSSe and NiSSe exhibit low maximum uphill free-energy changes for SRR, with Delta Gmax values of only 0.17 and 0.09 eV, respectively. In addition, low Li2S decomposition barriers of 0.36 and 0.38 eV are obtained. Electron localization function, charge density difference, and crystal orbital Hamilton population analyses further clarify the mechanism behind the excellent performance. Among the investigated systems, GeSSe and NiSSe exhibit the most promising bifunctional performance for simultaneous polysulfide immobilization and catalytic conversion.

Lithium-ion capacitors (LICs) promise to bridge the gap between high-energy batteries and high-power super-capacitors. While strategies like introducing oxygen-containing functional groups can boost the capacity of porous carbon cathodes, these same active sites become a critical failure point at high voltages, causing catastrophic electrolyte decomposition. To resolve this conflict, we introduce a novel interfacial regulation strategy that uses precise fluorine doping to selectively passivate these highly reactive surface defects on porous carbon. This passivation constructs a robust and electrochemically stable interface that effectively suppresses parasitic side reactions, enabling the stable operation of the cathode up to an ultra-high voltage 5.0 V. Consequently, the full LIC device delivers a high energy density of 231.1 Wh kg-1 and maintains exceptional cycling longevity, with over 92% capacity retention after 3000 cycles at a high current density. This study therefore redefines the design focus for high-voltage cathodes, shifting from capacity enhancement to targeted interfacial stabilization. This strategic pivot is instrumental in creating next generation LICs that deliver a practical and compelling combination of energy density, power, and durability.

Silicon-based anodes offer high theoretical capacity but suffer from severe volume expansion during cycling, leading to structural degradation and rapid capacity fade. While submicron silicon (Si) particles are industrially preferred for their practical advantages, their larger size exacerbates these issues. Carbon coating is an effective strategy to mitigate such problems, but conventional methods often fail to establish robust interfacial bonding. Constructing synergistic Si-O-C and Si-C bonds is critical for achieving mechanical stability and efficient ion/ electron transport. However, conventional carbonization typically yields randomly mixed interfaces and struggles to produce high Si-C bond content without extreme temperatures. Achieving abundant Si-C bonds and precisely regulating the spatial gradient between Si-O-C and Si-C remains particularly difficult for submicron Si. Herein, we develop a stepwise carbonization strategy using a hybrid carbon source to construct a gradient-distributed Si-C/Si-O-C composite dual-bond interface on submicron Si. This approach enables the in situ conversion of Si-O-C to Si-C, forming a stable and well-organized interfacial structure. The resulting composite with 55 % Si loading exhibits a high specific capacity of 1050 mAh/g after 1000 cycles, demonstrating exceptional long-term cycling stability and kinetics.

Li-CO2 batteries have attracted considerable attention due to their dual functions in energy storage and CO2 utilization. However, their practical application remains hindered by large overpotentials and poor cycling stability. Based on first-principles calculations, this work studied the performance of β12-borophene-supported 3d transition-metal single-atom and dual-atom catalysts (M/β12 and M-M/β12, M = V-Zn) as cathodes for Li-CO2 batteries. As the atomic number decreases, the d-band center of the catalyst shifts upward toward the Fermi level, enhancing CO2 adsorption and activation. Dual-atom catalysts (M-M/β12) exhibit superior catalytic performance compared to their single-atom counterparts (M/β12), due to the d-d orbital hybridization between neighboring metal centers. This hybridization optimizes the active-site electronic configuration, enhances CO2 adsorption/activation, and reduces the reaction overpotential. Notably, V-V/β12 exhibits an ultralow charge-discharge overpotential of 0.48 V and a Li2CO3 dissociation barrier of 0.84 eV, displaying exceptional activity. Mechanistic analysis shows that CO2 undergoes parallel adsorption via C and O atoms at dual-V sites, where extensive d-p orbital hybridization and multicenter electronic coupling activate the CO bond. The electronic synergy from d-d hybridization is key to the enhanced performance of dual-atom catalysts, offering new insights for designing efficient Li-CO2 battery cathodes.

The geometric, electronic, and optical properties of the WTe2/InP heterostructure are systematically explored by means of first-principles calculations. The H1 WTe2/InP heterostructure presents a type-II band alignment with an indirect band gap of 0.9666 eV according to electronic property calculations. It exhibits tunable band gap, reversible semiconductor-metal transition, and controllable conversion between type-II and type-I band alignments under external electric field and strain. The optical properties of the monolayers and heterostructure are also systematically studied. The results demonstrate that the WTe2/InP heterostructure exhibits outstanding optical absorption performance compared to the monolayers in most of the ultraviolet and partial visible spectral ranges, and its optical absorption coefficient can be effectively tuned by applying external electric field and strain. This study reveals that the H1 WTe2/InP heterojunction is promising for applications in light-emitting diodes, flexible electronic devices, and ultraviolet detection fields.

The multi-electron transfer capability of iodine renders it a promising conversion-type cathode for aluminum-ion batteries. However, conventional aluminum/iodine (Al/I2) batteries typically operate via the I0 (or I3 -)/I- redox couple at low voltages, leaving the high-potential I+/I0 redox largely unexplored and limiting both capacity and energy density. Herein, we develop high-performance Al/I2 batteries by employing iodine-rich 1D perovskite cathodes that leverage the thermodynamically favorable ionic liquid electrolyte environment to achieve a four-electron I+/I0/I- redox process. These perovskite cathodes lower the reaction barrier for I+/I0 conversion and suppress the shuttle effect of iodine species through hydrogen bonding and halogen bonding interactions, ensuring cycling stability and a stable environment for four-electron transfer reaction. The I+ formed can be effectively stabilized by AlCl4 -, further accelerating the reaction kinetics. Through organic and metal cation engineering to modulate bonding interactions and electronic properties, the benzamidinium and Bi3+-based perovskite (PFABiI4) cathode achieves a high specific capacity of 311.2 mAh g-1 I at 0.2 A g-1 and exceptional cycling stability, with a capacity decay rate of only 0.0056% per cycle over 8000 cycles at 2 A g-1. This work opens an avenue for designing high-voltage, high-energy-density, and long-cycle-life Al/I2 batteries.

Electrocatalytic C-N coupling for urea synthesis offers a sustainable alternative to conventional industrial processes, yet its efficiency is hindered by challenges of activating inert reactants and controlling the competing reaction pathways. Here, we employ first-principles calculations to systematically investigate a series of transition-metal-doped Nb2C MXenes (TM@Nb2C, TM = 3d/4d metals) as catalysts for urea synthesis from CO and N2. Our findings establish that TM doping is a powerful strategy to modulate the local Lewis acidity of surface metal sites, which in turn governs the adsorption and activation of reactants and intermediates. Through a multi-step screening process based on stability, activity, and selectivity, Cu@Nb2C emerges as a superior catalyst. It exhibits an exceptionally low limiting potential (-0.34 V), a modest kinetic barrier for C-N coupling (0.58 eV), and high selectivity against competing hydrogen evolution and nitrogen reduction. To quantitatively link the catalytic performance to Lewis acidity, we introduce the solvated relative fluoride ion affinity as a robust descriptor, using HF as a probe molecule. A distinct volcano-type relationship is uncovered between this descriptor and the urea synthesis activity. Cu@Nb2C sits precisely at the volcano apex, where its moderate Lewis acidity achieves an optimal balance in the free energy landscape of all elementary steps. This work not only identifies Cu@Nb2C as a promising electrocatalyst but also establishes a novel, generalizable framework for quantifying surface Lewis acidity, offering a new design principle for high-performance urea electrocatalysts and beyond.