Uncontrolled proton activity in aqueous electrolytes triggers detrimental side reactions that compromise the stability of zinc (Zn) metal anodes. To address this challenge, we propose a full-process proton regulation strategy enabled by the unique β-1,4-glycosidic framework of chitosan oligosaccharide (COS). The rigid COS backbone effectively constrains proton generation and transport in the electrolyte, while its preferential interfacial adsorption constructs an ultrathin molecular barrier that inhibits proton consumption at the Zn surface. This dual-function molecular architecture synergistically realizes "generation-transport-consumption" proton regulation, thereby delivering exceptional electrochemical performance: long-term cycling stability over 8,000 h in Zn||Zn symmetric cells, an average Coulombic efficiency of 99.84% over 2,300 cycles in Zn||Cu cells, and superior cycling stability for more than 2,000 cycles at 2 A g-1 in Zn||MnO2 full cells. This work reveals glycosidic frameworks as a universal and transferable design principle for aqueous batteries, shifting electrolyte design from functional group-centric optimization to framework-enabled regulation toward sustainable, high-performance energy storage.

The rapid and selective removal of carcinogenic hexavalent chromium (Cr(VI)) from water remains a critical challenge for sustainable environmental remediation. This work reports the elaborate design of oxygen-vacancy-rich MnFe2O4@ZnFe2O4 (MZFO-V-O) heterojunction microspheres for highly efficient microwave-assisted Cr(VI) reduction under mild conditions. At an initial pH of similar to 7, with a catalyst dosage of 2 g L-1 and a temperature of 100 degrees C, the MZFO-V-O heterojunction composite achieved complete removal of Cr(VI) from a 50 mg L-1 solution within 35 min under microwave irradiation. Density-functional theory calculations revealed that the introduced vacancies reduced the work function to 4.66 eV, suggesting a lowered energy barrier for bulk-to-surface electron migration. Moreover, Fe-O anchoring sites were identified as the active centers that enable efficient adsorption and reduction of dichromate ions, which is accompanied by significant charge transfer from Fe to the adsorbate. The synergistic coupling of defect-induced polarization and conduction losses, and efficient microwave absorption collectively underpins the high activity and operational stability of MZFO-V-O. These findings establish a clear design route for next-generation microwave catalysts and highlight the practical potential of vacancy-modulated ferrite heterostructures for rapid, energy-efficient treatment of Cr(VI)-contaminated water.

Lithium metal batteries (LMBs) hold great promise for next-generation energy storage systems owing to their high theoretical energy density. However, their practical application is hindered by uncontrolled Li dendrite growth and unstable solid electrolyte interphase (SEI). Here, we design a Li3Sb-modified Cu current collector (Li3Sb@Cu) that employs a synergistic dual-function strategy to regulate uniform Li plating and engineer a robust LiF-rich SEI. The Li3Sb interface is constructed in situ by electrochemical lithiation of Cu2Sb layer that is directly grown on Cu foil via a galvanic replacement reaction in SbCl3 solution. Lithiophilic Li3Sb interlayer, with high delithiation potential and strong adhesion to the Cu substrate, significantly lowers the Li nucleation overpotential (34 mV at 1.0 mA cm-2). Moreover, the Li3Sb preferentially adsorbs and catalytically decomposes fluoroethylene carbonate, producing a mechanically robust, LiF-rich SEI. Consequently, the Li3Sb@Cu enables stable Li plating/stripping for over 800 h and achieves an average Coulombic efficiency of 98.2% over 180 cycles. When paired with a LiFePO4 cathode, the full cell delivers a high discharge capacity of 137.4 mAh g-1 and retains 96.6% capacity after 130 cycles at 1 C. This work presents a synergistically bifunctional interlayer on Cu foils that regulates Li nucleation and stabilizes the SEI for high-performance LMBs.

Nanostructured titanium oxynitride (TiNxO1-x) is a promising pseudocapacitive material due to its large pseudocapacitance and high conductivity. However, the synthesis of nonlayered two-dimensional (2D) TiNxO1-x is challenging and the pseudocapacitive energy storage mechanism of TiNxO1-x is still unclear. Herein, accordionlike 2D TiNxO1-x nanosheets intercalated with nitrogen-doped graphene (TiNxO1-x/NG) are controllably fabricated by a spatially confined thermal nitridation of 1,8-diaminooctane intercalated H0.8Ni0.4Ti1.6O4 & sdot;H2O nanosheets. In situ electrochemical characterizations and theoretical calculations reveal the pseudocapacitance originates from the Faradic reaction between H+ and N-Ti-O species accompanied by Ti valence state change and the pseudocapacitance of TiNxO1-x/NG is determined by the N-Ti-O content instead of the N/O ratio. Compared to TiNxO1-x, the electrons transfer from sandwiched NG to TiNxO1-x enhances H+ adsorption at N active sites of N-Ti-O within TiNxO1-x/NG, giving rise to enhanced pseudocapacitance and cycling stability. Consequently, the TiNxO1-x/NG shows a large volumetric capacitance of 739.2 F cm-3 (616.0 F g-1) at 1 A cm-3 and superior cyclability with 98.5 % capacitance retention after 10,000 cycles, surpassing previously reported metal oxynitrides and nitrides. The results provide insights into the controllable synthesis of 2D nonlayered TiNxO1-x and elucidate the pseudocapacitive charge storage mechanism of metal nitrides or oxynitrides.

The transformation of agricultural waste into valuable materials for environmental remediation has garnered significant attention in sustainable materials science. This study introduces a novel ZnFe2O4/SnS2/bagasse-derived cellulose composite aerogel for the microwave-assisted catalytic reduction of hexavalent chromium (Cr(VI)) in wastewater, highlighting an innovative use of agricultural waste in environmental remediation. This composite aerogel leverages the unique properties of cellulose extracted from waste bagasse combined with ZnFe2O4 and SnS2 nanoparticles, optimizing the structural benefits such as extensive surface area and enhanced porosity. Under microwave irradiation, the aerogel efficiently catalyzed the reduction of Cr(VI) (100 mL, 100 mg/L) by up to similar to 99 % within 40 min, even in near-neutral aqueous environments, outperforming many conventional catalysts. Furthermore, mechanistic insights provided by density functional theory (DFT) calculations reveal that the heterojunctions within the composite aerogel enhance electron mobility, thereby catalyzing the reduction process more effectively. The interaction between the cellulose matrix and the ZnFe2O4 and SnS2 creates a dynamic environment for the rapid and energy-efficient reduction of Cr(VI), leveraging both chemical and physical synergies. This research not only highlights the potential of microwave-assisted processes in environmental applications but also emphasizes the sustainable use of agricultural waste as a resource for crafting advanced materials.

Alkali activation is a common method to prepare commercial porous carbon. In a mixed alkali activation system, the role of each individual alkali has generally been assumed to be the same as in a single alkali activation system, and the low corrosiveness of weak alkalis has mainly been emphasized. However, the intrinsic roles of the individual alkalis should be understood in detail and redefined to illuminate the activation pathways from the perspective of internal chemical reactions rather than corrosiveness. Herein, by combining in situ TG-MS analysis, DFT calculation and other characterizations, the activation processes were precisely tracked, and activation pathways were proposed. In the mixed alkali activation system, the strong alkali KOH served as the activation promoter, first decomposing into K2O, which then attacked the C-C bonds to form active reaction sites defined as pore seeds. The weak alkali K2CO3 acted as the activation pathway modifier; CO3 2- preferentially etched the pore seeds over K2O due to the lower reaction barrier of CO3 2- interacting with the pore seeds. Consequently, the rough etching reaction of KOH was replaced and suppressed by the gentler action of CO3 2-, forming more micropores. When the ratio of strong to weak alkali was 1 : 1, the obtained CK1K2-122 exhibited the highest microporosity (82.61%) and a high specific surface area (1962.18 m2 g-1). It exhibited a high specific capacitance of 296.7 F g-1 and excellent cycling stability with 98.3% retention after 10 000 cycles. The supercapacitor demonstrated a high energy density of 114.4 W h kg-1 at a power density of 17.5 kW kg-1, with a broad potential window of 3.5 V.

Achieving the real-time detection of hydrogen sulfide (H2S) based on metal oxide semiconductor (MOS) gas sensors is of great significance for rapid disease diagnosis. However, the high-power consumption and poor selectivity severely limit its practice application. In this study, a platinum nanoparticle (Pt NPs)-loaded porous metal-organic framework (MOF)-derived SnO2 material was successfully synthesized to optimize the H2S-sensing performance at room temperature. The optimized Pt-loaded porous SnO2-based gas sensor exhibited remarkably high sensitivity (712-10 ppm), fast response (21 s), good selectivity, and extremely low detection limit for H2S (10 ppb) at room temperature. The in-depth analysis demonstrated that the porous structure of Sn-MOF can provide adequate active reaction sites for gas molecules. Moreover, the uniform distribution of surface-loaded Pt NPs can initiate electron and chemical sensitization effects, thereby improving the sensing performance. The successful application of Pt NPs provides a novel approach to improve the room-temperature (RT) sensing performance of metal-oxide-semiconductor-based gas sensors.

Developing efficient and durable single-atom catalysts is vitally important for the sulfur redox reaction (SROR) in Li−S battery, while it remains enormous challenging. Herein, undercoordinated Ni−N 3 moieties anchored on N,S-codoped porous carbon (Ni−NSC) is obtained to enhance the SROR. The experiments and theoretical calculations indicate that the symmetry-breaking charge transfer in Ni single-atom catalyst originates from tuning effect of sulfur atoms mediated Ni−N 3 moieties, which can both facilitate the chemical adsorption by formation of N−Ni⋅⋅⋅S n 2− , and achieve a rapid redox conversion of polysulfides because of the enhanced electron transfer. As results, the Ni−NSC based Li−S battery delivers a very high initial reversible capacity (1025 mAh g −1 at 1 C), as well as outstanding cycling-stability for 2400 cycles at 2 C and 3 C, respectively. Noteworthy, the areal capacity can reach 7.8 mAh cm −2 at 0.05 C and a retention capacity of 4.7 mAh cm −2 after 100 cycles at 0.2 C for Ni−NSC based Li−S battery with sulfur loading of 5.88 mg cm −2 . This work provides profound insight for rational optimizing microscopic electronic density of active site to promoting SROR in metal-sulfur batteries.

Constructing heterostructures is an effective way to improve the carrier mobility for metal oxide sensing material, since heterojunctions are usually built only on the surface of the material, the carrier transport efficiency inside the material still needs to be improved. In this paper, BiVO4 nanocrystals (BVO NCs) with an average size of 1 nm generated by pulsed laser irradiation were embedded in situ at the particle boundaries (PBs) of SnO2 nanofibers to form an effective n-n heterojunctions inside the material. After embedding the BVO NCs in the SnO2 samples, the response value for 10 ppm NO was improved to 48.91, which was 2.5 times higher than that of pure SnO2 at near room temperature (50 °C). Meanwhile, the detection limit was lowered to 50 ppb with excellent long term stability. Detailed analysis and theoretical calculations demonstrated that the formation of abundant n-n heterojunctions not only promotes the electron-hole separation and the carrier mobility, but also reduces the conductivity and adsorption energy of the material, which significantly improves its sensing performance. This work demonstrates a new approach to modulate the gas-sensing performance of metal oxide semiconductors by generating heterostructure inside the bulk of the material.

Metal oxides based semiconductors promise high performance gas sensing owing to their robustness and low cost, but are limited by their unsatisfied adsorption ability and intrinsic low carriers' mobility. We herein demonstrate an efficient strategy of reducing the adsorption energy and improving the carrier mobility via bulk implanted TiO2 nanocrystals (NCs) in LaFeO3 porous structure. By implanting laser generated sub-3 nm TiO2 NCs in LaFeO3 samples, the response value (221.8 for 100 ppm formaldehyde) increases about 4 times comparing with that of pristine. Additionally, the sample exhibits high sensitivity and fast response/recovery speed toward formaldehyde steam. The detailed analyses and theoretical calculation proves that the TiO2 NCs could cause the increase of adsorbed oxygen levels as well as the carrier mobility through forming the heterojunction with LaFeO3. This work verifies that TiO2 NCs implanted LaFeO3 is a promising formaldehyde sensing material, which provides a new approach to improve sensing ability of metal oxide semiconductor (MOS) based gas sensors.

Li-S batteries are regarded as promising devices for energy storage systems owing to high energy density, low cost, and environmental friendliness. However, challenges of polysulfides shuttling in sulfur cathode and dendrite growth of lithium anode severely hinder the practical application. Developing advanced skeletons simultaneously regulating the cathode and anode is significant and challenging. Hence, a novel and scalable strategy combining spray drying and topological nitriding is proposed, and hierarchically assembled rGO hollow microspheres encapsulated highly porous nanospheres consisted of ultrafine Nb4N5-Nb2O5 or Nb4N5 nanoparticles as multifunctional skeletons for S and Li are designed. In such unique architecture, a 3D highly porous structure provides abundant void space for loading of S and Li, and accommodates volume change during cycling. Moreover, Nb4N5-Nb2O5 heterostructured interface promotes adsorption-conversion process of polysulfides, while strong lithophilic Nb4N5 induces the selective infiltration of Li into the void of the skeleton and regulates the uniform deposition and growth. More interestingly, in situ generated Li3N@Nb ion/electron conducting interfaces induced by the reaction of Nb4N5 and Li reduce the nucleation overpotential and induce selective deposition of Li into the cavity. Consequently, the Li-S full cell exhibits superior cycling stability and impressive rate performance with a low capacity ratio of negative/positive.

Developing advanced high voltage lithium-metal batteries (LMBs) with superior stability and intrinsic safety is of great significance for practical applications. However, the easy flammability of conventional carbonate solvents and inferior compatibility of commercial electrolytes for both highly reactive Li anodes and high-voltage cathodes severely hinder the implementation process. Hence, we rationally designed an intrinsically nonflammable and low-cost phosphate electrolyte toward stable high-voltage LMBs by bidirectionally modulating the interphases. Benefiting from the synergistic regulation of LiNO3 and DME dual-additives in the 1.5 M LiTFSI/Triethyl phosphate electrolyte, thin, dense and robust electrodes/electrolyte interphases were well constructed simultaneously on the surfaces of Li anode and Ni-rich cathode, dramatically improving the stability and compatibility between electrodes and electrolyte. Consequently, boosted kinetic and high Coulombic efficiency of 98.6% for Li metal plating/stripping over 400 cycles and superior cycling stability of exceeding 4,000 h in Li symmetric cell is achieved. More importantly, the Li∥LiNi0.6Mn0.2Co0.2O2 cell assembled with a thin Li anode and high mass-loading cathode at a high cutoff voltage of 4.6 V retains a 98.4% capacity retention after 500 cycles at 1C. This work affords a promising strategy to develop nonflammable electrolytes enabling the high safety, good cyclability, and low cost of high-energy LMBs.

The serious shuttle effect and sluggish reaction kinetics intrinsically handicap the practical application of Li‐S batteries. Herein, a unique 3D hierarchically porous Mott–Schottky electrocatalyst composed of W 2 C quantum dots (QD) spatially confined in nitrogen‐doped graphene microspheres (NGM) is proposed for regulating the kinetics of sulfur electrochemistry. Experimental and theoretical results disclose a spontaneous charge rearrangement and induce built‐in electric field across the W 2 C QD/NGM heterojunction interface, contributing to reduced energy barrier for both polysulfides reduction and Li 2 S oxidation during entitle discharge/charge processes. Furthermore, the ultrasmall W 2 C QD with high electrocatalytic activity and superior conductivity can promote the conversion of S species, while the hierarchically porous microspheres assembled from wrinkled graphene nanosheets not only can efficiently inhibit the polysulfides shuttling via multiple spatial confinement, but also provide abundant inner space for stable reservation of active S, highly conductive networks, and maintain the structural integrity of cathode during consecutive cycling. Consequently, Li‐S batteries employed with the designed W 2 C QD/NGM‐based cathode exhibit outstanding electrochemical properties even at a high sulfur loading. The superior performance combined with the simplicity of the synthesis process represents a promising strategy for the rational design of advanced electrocatalyst for energy applications.

Ultrathin and air-stable Li metal anodes hold great promise toward highenergy and high-safety Li metal batteries（LMBs）. However, the application of LMBs is technically impeded by existing Li metal anodes with large thickness,high reactivity, and poor performance. Here, we developed a novel and scalable approach for the construction of a 10-μm-thick flexible and airstable Li metal anode by conformally encapsulating Li within a multifunctional VN film. Specifically, the highly lithiophilic VN layer guides a uniform deposition of Li, while abundant and multilevel pores arising from assembly of ultrathin nanosheets enable a spatially confined immersion of metallic Li, thus ensuring an ultrathin and sandwiched Li anode. More impressively, the strong hydrophobicity of VN surface can effectively improve the stability of anode to humid air, whereas the highly conductive framework greatly boosts charge transfer dynamics and enhances Li utilization and highrate capability. Benefiting from such fascinating features, the constructed LiVN anode exhibits ultrastable cycling stability in both ether（2500 h） and carbonate（900 h） electrolytes, respectively. Moreover, even exposed to ambient air for 12 h, the anode still can retain ～78% capacity, demonstrating excellent air-defendable capability. This work affords a promising strategy for fabricating high-performance, high-safety, and low-cost LMBs.

Great efforts are exploring single-atom (SA) sites for tailoring catalytic effects on the sulfur-related redox reaction in Li-S battery, while edge-distributed SA sites lack attention. Herein, we implanted SA iron sites in N-doped porous carbon on CNTs (Fe-NPC@CNTs) to obtain edge-distributed FeN4 moieties via a polymer inductive strategy. The Fe-NPC@CNTs own enhanced “trapping-conversion” ability for polysulfides. The Li-S battery based on Fe-NPC@CNTs achieves a wonderful capacity of 1004 mAh g-1 at 1 C with long-term cycling stability, where the capacity fading rate is 0.032% per cycle over 1200 cycles. Noteworthy, the cell delivers very large capacities of 3.94/6.12 mAh cm-2 under high sulfur loadings of 4.50/5.04 mg cm-2 at 0.5/0.2 C, corresponding to 82.5/82.4% capacity retentions over 100 cycles. Under ultrahigh sulfur loadings (7.8/10.9 mg cm-2), the cell exhibits amazing large areal capacities of 7.63/10.76 mAh cm-2. The edge-distributed SA sites engineering provides a bright blueprint for advanced Li-S battery.

The development of earth-abundant electrocatalysts with Pt-like catalytic activity for the hydrogen evolution reaction (HER) is of great significance to green hydrogen production. Herein, a novel strategy is described to construct dual-phase nitride nanobelts composed of Mo2N and Ni0.2Mo0.8N by nitridation of Ni2+ intercalated layered MoO3 nanobelts (NBs). The Mo2N/Ni0.2Mo0.8N catalyst exhibits superior stability and a low over-potential of 26 mV at 10 mA cm(-2) and Tafel slope of 31 mV dec(-1) in both the alkaline electrolyte and simulated seawater, which is comparable to or better than that of the benchmark Pt/C catalyst. The excellent alkaline HER characteristics is attributed to the Mo2N/Ni0.2Mo0.8N heterostructure with adjustable content and robust interfaces and without metal Ni segregation and structure collapse during nitridation. Density-functional theory (DFT) calculations and experiments reveal that the Mo2N/Ni0.2Mo0.8N interface with strong electronic interactions optimizes H adsorption/desorption yielding moderately weak bonding metal sites with positive Delta G(H)* as the catalytic centers, thereby accelerating the HER kinetics and boosting the HER activity. The results reveal a simple strategy for the preparation of heterostructured nitride-based catalysts with Pt-like activity for hydrogen evolution.

Despite lithium-sulfur (Li-S) batteries possessing ultrahigh energy density as great promising energy storage devices, the suppressing shuttle effect and improving sulfur redox reaction (SROR) are vital for their practical application. Developing high-activity electrocatalysts for enhancing the SROR kinetics is a major challenge for the application of Li-S batteries. Herein, single-molecule iron phthalocyanine species are anchored on the N and P dual-doped porous carbon nanosheets (Fe-NPPC) via axial Fe-N coordination to optimize the electronic structure of active centers. The Fe-NPPC can promote the catalytic conversion of polysulfides by modulation of the electronic density in active moieties, endowing the Li-S battery with a high reversible capacity of 1023 mAh g(-1) at 1 C as well as an ultralow capacity decay of 0.035% per cycle over 1500 cycles. Even with a high sulfur loading of 7.1 mg cm(-2), the Li-S battery delivers a high areal capacity of 4.8 mAh cm(-2) after 150 cycles at 0.2 C. With further increasing the sulfur loading to 9.2 mg cm(-2), an excellent areal capacity of up to 9.3 mAh cm(-2) is obtained at 0.1 C.

An atomically distributed asymmetrical five-coordinated Co–N5 anchored on N-rich doped carbon (CoN5 SA/NC) is prepared via a urea-mediated pyrolysis strategy and used as a highly efficient sulfur redox reaction electrocatalyst for application in Li–S batteries.

锂硫电池因高比容量、高能量密度、低成本和环境友好等显著优点,有望成为取代锂离子电池的下一代高比能电池。然而,锂硫电池的实际应用严重受限于电极材料中存在的系列问题,如较低的离子/电子传导性、多硫化物的穿梭效应、充放电中较大的体积变化和锂负极的稳定性等。将硫与各类载体材料结合来提高活性材料的利用率和电池循环稳定性成为当前的研究热点。在已报道的各类载体材料中,具有丰富的孔道和开放活性位点的金属有机框架及其衍生物材料因其优异的结构特点引起了人们的广泛关注。总结了金属有机框架及其衍生物在提高硫正极循环稳定性中的应用进展,并对其在锂硫电池中的发展趋势进行了展望。