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The threat posed by biological and chemical warfare agents (BCWA) to national security, the environment, and personal health underscores the need for innovative chemical protective clothing. To address the limitations of conventional activated carbon materials, which are prone to falling off and adsorption saturation, an efficient self-association approach was introduced. In this study, we proposed the immobilization of metal–organic framework (MOF) 808 and Ag nanoparticles onto a polypropylene (PP) fiber membrane using a rapid self-association method facilitated by chitosan (CS). The MOF 808/Ag-based (PP-CS/808-Ag) fiber membrane demonstrated exceptional degradation efficiency, achieving a remarkable rate of t1/2within 2 h for the mustard simulant 2-chloroethyl ethyl sulfide (2-CEES) and a rate of t1/2= 4.12 min for the G-series simulant dimethyl 4-nitrophenylphosphate (DMNP). A theoretical computational model was developed to determine the overall reaction mechanism, and it was verified that MOF 808 and Ag nanoparticles were mainly involved in the hydrolysis process against 2-CEES and DMNP. The PP-CS/808-Ag composite fiber film was prepared as the core layer, and the fracture strength, bending resistance, and moisture permeability were better than those specified by many countries for biochemical protective clothing, showing that it has a broad application prospect in developing a generation of broad-spectrum bioprotective clothing.

The nonuniform electric field at the surface of a zinc (Zn) anode, coupled with water-induced parasitic reactions, exacerbates the growth of Zn dendrites, presenting a significant impediment to large-scale energy storage in aqueous Zn-ion batteries. One of the most convenient strategies for mitigating dendrite-related issues involves controlling crystal growth through electrolyte additives. Herein, we present thiamine hydrochloride (THC) as an electrolyte additive capable of effectively stabilizing the preferential deposition of the Zn(002) plane. First-principles calculations reveal that THC tends to adsorb on Zn(100) and Zn(101) planes and is capable of inducing the deposition of Zn ion onto the (002) plane and the preferential growth of the (002) plane, resulting in a flat and compact deposition layer. A THC additive not only effectively suppresses dendrite growth but also prevents the generation of side reactions and hydrogen evolution reaction. Consequently, the Zn||Zn symmetric battery exhibits long-term cycling stability of over 3000 h at 1 mA cm–2/1 mAh cm–2and 1000 h at 10 mA cm–2/10 mAh cm–2. Furthermore, the NH4V4O10||Zn full battery also displays excellent cycling stability and a high reversible capacity of 210 mAh g–1after 1000 cycles at 1 A g–1, highlighting a significant potential for practical applications.

Lithiophilicity optimization is the key to dendrite-free Li metal anode development. The effect of lithiophilicity in host construction, artificial SEI fabrication, and surface property regulation to suppress Li dendrite growth are discussed.

Carbon nitride, a typical low-dimensional conjugated polymer photocatalyst, features a high exciton binding energy due to the weak dielectric screening and the strong Coulombic attraction of photogenerated electrons and holes. The reduction of the exciton binding energy of carbon nitride to promote the conversion from excitons into free carriers is the first priority for the improvement of charge-transfer-dependent photocatalytic reaction activity. In this paper, by introducing a variety of polar metal cations to carbon nitride, it is demonstrated that the charge distribution of the heptazine ring can be improved by ion polarization, which effectively promotes the dissociation of excitons into electrons and holes. The sodium ion shows the best modification effect, which enhances the rate of both photocatalytic hydrogen and hydrogen peroxide production by about 50 %. Characterization shows that the introduction of strongly polar metal cations contributes to the reduction of the exciton dissociation energy of carbon nitride. This study provides a new perspective and a convenient method for the exciton modulation engineering of low-dimensional photocatalysts.

The amount of atomically dispersed Fe-N-P-C active sites determines the over-all ORR activity of the catalyst material, which is successfully tuned by the Fe loading in the material.

Research in the sustainable conversion of biomass to fuels and chemicals is a necessity for the reduction of the carbon footprint in transport energy. Herein, we demonstrate an efficient tandem catalyst to selectively convert (simulated) bio-oil to hydrocarbons with enhanced C4+fuel yield in a fixed bed reactor of a small pilot plant. The tandem catalytic system is a multifunctional dual bed system; carbon coupling catalysts (0.2 wt % X-TiO2(X: Ru, Pd, Au) at the upper layer and hydro-deoxygenation (Ru-MoFeP/Al2O3) at the bottom layer in a single fixed bed reactor. The upper-bed catalysts facilitated the carbon coupling reaction of C2–C4light oxygenates and significantly reduced the light gases yield (C1–C5) to ca. 40% and increased the organic (C4+) phase ca. 15%. The analysis of the organic phase suggests that among the screened upstream catalysts, 0.2 wt % Ru/TiO2||Ru-MoFeP/Al2O3recorded the optimum activity. The coupled light oxygenates (acetone) alkylated with the phenolic compounds and sequentially hydro-deoxygenated to yield higher C4+hydrocarbons. This versatile tandem catalytic approach has a potential application in the emerging biorefinery concept.

Transition-metal selenides have emerged as promising anode materials for sodium ion batteries (SIBs). Nevertheless, they suffer from volume expansion, polyselenide dissolution, and sluggish kinetics, which lead to inadequate conversion reaction toward sodium and poor reversibility during the desodiation process. Therefore, the transition-metal selenides are far from long cycling stability, outstanding rate performance, and high initial Coulombic efficiency, which are the major challenges for practical application in SIBs. Here, an efficient anode material including an FeSe2core and N-doped carbon shell with inner void space as well as high conductivity is developed for outstanding rate performance and long cycle life SIBs. In the ingeniously designed FeSe2@NC microrods, the N-doped carbon shell can facilitate mass transport/electron transfer, protect the FeSe2core from the electrolyte, and accommodate volume variation of FeSe2with the help of the inner void of the core. Thus, the FeSe2@NC microrods can maintain strong structural integrity upon long cycling and ensure a good reversible conversion reaction of FeSe2during the discharge/charge process. As a result, the as-prepared FeSe2@NC microrods exhibit excellent sodium storage performance and ultrahigh stability, achieving an excellent rate capability (411 mAh g–1at 10.0 A g–1) and a long-term cycle performance (401.3 mAh g–1after 2000 cycles at 5.0 A g–1).

TiC/C core/shell nanowires arrays are prepared viaa simple chemical vapor deposition method and show superior cycling performance and good high-rate performance as anode of sodium ion batteries.

Abstract: Electrochemical energy storage systems such as fuel cells and metal–air batteries can be used as clean power sources for electric vehicles. In these systems, one necessary reaction at the cathode is the catalysis of oxygen reduction reaction (ORR), which is the rate-determining factor affecting overall system performance. Therefore, to increase the rate of ORR for enhanced system performances, efficient electrocatalysts are essential. And although ORR electrocatalysts have been intensively explored and developed, significant breakthroughs have yet been achieved in terms of catalytic activity, stability, cost and associated electrochemical system performance. Based on this, this review will comprehensively present the recent progresses of ORR electrocatalysts, including precious metal catalysts, non-precious metal catalysts, single-atom catalysts and metal-free catalysts. In addition, major technical challenges are analyzed and possible future research directions to overcome these challenges are proposed to facilitate further research and development toward practical application. Graphic Abstract:

The lattice oxygen evolution and P2-O2 phase transition of P2-Na2/3Ni1/3Mn2/3O2at deep charging were suppressed by the combined action of dielectric effect of MgFe2O4coating and Mg, Fe co-doping.

The binder-free flexible carbon paper (FCP) supported mutil-wall carbon nanotubes (CNTs) were synthesized via CVD method. Subsequently, polyaniline was deposited on the surface of CNTs/FCP, which was followed by polyaniline carbonization and KOH activation to obtain nitrogen-doped (N-doped) carbon/CNTs/FCP composite. The Raman spectroscopy, scanning electron microscope, transmission electron microscope investigation indicated that N-doped carbon/ CNTs/FCP was formed after the polyaniline carbonization and KOH activation, without destroying the intrinsic CNTs structure. Compared to the pristine CNTs/FCP, of which the specific capacitance(Csp) was 5.23 F/g and 8.24 F/g in 1M H2SO4 and 0.5M KOH solution respectively, the reversible Csp of N-doped carbon/CNTs/FCP reached 193.3 F/g (1M H2SO4) and 161.0 F/g (0.5M KOH), at the current density of 1 A/g. Moreover, this 3D structure N-doped carbon/CNTs/FCP shows good hydrophility and excellent cycling performance with little capacitance loss over long term galvanostatic charge-discharge, which is a promising electrode material for supercapacitor application.

The rational electrode design is one of the most important ways to enhance the electrochemical properties of lithium–sulfur batteries (LSBs). In this contribution, we use Ni-embedded porous graphitic carbon fiber (PGCF@Ni) as the scaffold to construct a novel cathode and anode for LSBs. With the help of elaborate surface engineering, the constructed solid electrolyte interface (SEI)@Li/PGCF@Ni anodes can effectively restrain the growth of lithium dendrites during the cycle, exhibiting an ultralow overpotential of ∼10 mV for 2000 h at 1 mA cm–2/1 mA h cm–2. The underlying mechanism is further investigated by COMSOL Multiphysics simulations. Additionally, the PGCF@Ni/S cathode fabricated by the molten sulfurizing method manifests superior rate performance and stability. Ultimately, the assembled SEI@Li/PGCF@Ni||PGCF@Ni/S full battery exhibits prominent electrochemical property with a high capacity retention of about 77.9% after 600 cycles at 1 C. Such success at the performance improvement in LSBs may open up avenues toward other rational designs of high-quality electrodes in electrochemical energy storage.

Lithium-sulfur batteries (LSBs) are deemed as one of the most promising next-generation energy storage systems due to their high theoretical energy density. However, their intrinsic shortcomings hindered their practical commercialization. In this work, a powerful three-dimensional (3D) filter paper porous carbon decorated with cobalt [Co] (FPPC@Co) matrix is employed to fabricate high-quality anode and cathode simultaneously. Combining with in-situ surface engineering, the rationally designed solid electrolyte interphase [SEI]@Li/FPPC@Co anodes can plate/strip Li uniformly without Li dendrites, manifesting a low overpotential of about 20 mV for 1000 h at 1 mA/cm2/1 mA h/cm2. COMSOL Multiphysics simulations further testify the underlying mechanisms. Meanwhile, with the help of molten sulfurizing method, the synthesized FPPC@Co/S cathode exhibits excellent stability with high capacity retention of 73.3% after 200 cycles at 1 C. Furthermore, we paired SEI@Li/FPPC@Co anode and FPPC@Co/S cathode to assemble lithium-sulfur full cells. The SEI@Li/FPPC@Co||FPPC@Co/S full cell shows superior electrochemical performance with a long-term cycle life (a capacity retention of 88.7% after 200 cycles at 1 C). Insight gained from this work opens a new door for fabrication of high-quality electrodes for LSBs.

Microwave (MW) treatment was reported as an efficient method to prepare porous carbon-based electrode material with high capacity for a high-performance supercapacitor. Herein, the superiority of the mechanism of MW treatment was tried to be revealed by preparing a N and O co-doped porous activated carbon (MWAC) based on a heteroatom-rich corn cob and compared to that of the conventional heating method. The resulting MWAC has a large specific surface area of 2508 m2/g with hierarchical micro- and mesoporous structures and abundant heteroatom doping of O and N. In a three-electrode system, the MWAC shows a superior specific capacitance of 560 F/g at a discharge current density of 0.5 A/g in a 6 mol/L KOH aqueous electrolyte. The symmetric supercapacitor fabricated by MWAC electrodes in a 6 mol/L KOH electrolyte shows excellent capacity retention of 96.8%, even after 10 000 galvanostatic charge–discharge cycles at the current density of 1 A/g. The aqueous (6 mol/L KOH) symmetric supercapacitor delivers a high energy density of 9.24 Wh/kg at a power density of 250 W/kg. The results prove that the MW heating shows more superiority in retaining inherent heteroatoms and creating hierarchical micro- and mesoporous structures of activated carbon for supercapacitors with high performance.

The binder-free flexible carbon paper (FCP) supported mutil-wall carbon nanotubes (CNTs) were synthesized via CVD method. Subsequently, polyaniline was deposited on the surface of CNTs/FCP, which was followed by polyaniline carbonization and KOH activation to obtain nitrogen-doped (N-doped) carbon/CNTs/FCP composite. The Raman spectroscopy, scanning electron microscope, transmission electron microscope investigation indicated that N-doped carbon/ CNTs/FCP was formed after the polyaniline carbonization and KOH activation, without destroying the intrinsic CNTs structure. Compared to the pristine CNTs/FCP, of which the specific capacitance(Csp) was 5.23 F/g and 8.24 F/g in 1M H2SO4and 0.5M KOH solution respectively, the reversible Cspof N-doped carbon/CNTs/FCP reached 193.3 F/g (1M H2SO4) and 161.0 F/g (0.5M KOH), at the current density of 1 A/g. Moreover, this 3D structure N-doped carbon/CNTs/FCP shows good hydrophility and excellent cycling performance with little capacitance loss over long term galvanostatic charge-discharge, which is a promising electrode material for supercapacitor application.