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An in situ artificial LiF/Li–Sn solid electrolyte interface film possesses high Li+ conductivity and good electrical insulation, endowing the Li//LiFePO4 battery with 86.3% capacity after 1000 cycles.

The lithium (Li) ion and electron diffusion behaviors across the actual solid electrolyte interphase (SEI) play a critical role in regulating the Li nucleation and growth and improving the performance of lithium-sulfur (Li-S) batteries. To date, a number of researchers have pursued an SEI with high Li-ion conductivity while ignoring the Li dendrite growth caused by electron tunneling in the SEI. Herein, an artificial anti-electron tunneling layer with enriched lithium fluoride (LiF) and sodium fluoride (NaF) nanocrystals is constructed using a facile solution-soaking method. As evidenced theoretically and experimentally, the LiF/NaF artificial SEI exhibits an outstanding electron-blocking capability that can reduce electron tunneling, resulting in dendrite-free and dense Li deposition beneath the SEI, even with an ultrahigh areal capacity. In addition, the artificial anti-electron tunneling layer exhibits improved ionic conductivity and mechanical strength, compared to those of routine SEI. The symmetric cells with protected Li electrodes achieve a stable cycling of 1500 h. The LiF/NaF artificial SEI endows the Li-S full cells with long-term cyclability under conditions of high sulfur loading, lean electrolyte, and limited Li excess. This study provides a perspective on the design of the SEI for highly safe and practical Li-S batteries.

Lithium-sulfur (Li-S) batteries are widely considered to be next-generation storage technologies due to their high energy density, low cost and non-toxicity. However, the soluble lithium polysulfides (LiPS) migrating to the anode side inevitably causes side reactions with the Li anode, resulting in severe corrosion of the Li anode, loss of active materials, and rapid battery failure. Therefore, it is necessary to develop effective strategies to avoid LiPS exposure to Li anodes. Herein, a stable UiO-66-ClO

Metal-organic frameworks (MOFs) with intrinsically porous structures and well-dispersed metal sites are promising candidates for the oxygen evolution reaction (OER). However, the practical applications of MOFs for OER are significantly constrained due to their poor charge transfer property and insufficient inherent activity. Herein, we utilized caffeic acid as a bridging agent to covalently bond FeNi-MOF with NiMoO

In this study, we developed a facile method to fabricate three-dimensional (3D) structures composed of FeNi alloy nanoparticles encapsulated in N-doped carbon nanotubes that grafted on the SiO2 spheres (FexNiy@NCNT@SiO2) for electromagnetic wave (EMW) absorption. The experimental results suggest that the impedance matching characteristic can be tuned by the introduction of SiO2 spheres in the 3D structure. Density functional theory (DFT) calculations showed that the introduction of Ni improved the polarization and conductive losses of the FexNiy@NCNT@SiO2. As a result, the optimal 3D structure exhibits excellent EMW absorption property with a reflection loss and effective absorption bandwidth are -49.39 dB and 4.32 GHz, respectively, even though the matching thickness is only 1.6 mm, superior to most magnetic carbon-based composites. Thus, our current approach opens up an effective way to the development of low-cost, high-performance EMW absorbers.

V2CTX with a nanobelt structure was successfully prepared. A separator modified by V2CTX and KB was designed to accelerate redox kinetics and realize long-term cycling stability.

Li‒S batteries have shown great potential as secondary energy batteries. However, the side reaction between Li anodes and polysulfides seriously limited their practical application. Herein, the artificial protective film, which is consisted of Li-Nafion and TiO2, was designed and successfully prepared to achieve a corrosion-resistant Li anode in Li-S battery. In the composite protective film, the Li-Nafion could efficiently prevent the contact between Li anodes and polysulfides, and the incorporation of TiO2 nanoparticles into the Nafion could significantly increase the ionic conductivity and mechanical strength of the protective film. Li-Li symmetric cells with an optimal artificial protective film exhibited an extended cycle-life of 750 h at a current density of 1 mA/cm2 in Li2S8 electrolyte. Moreover, the Li‒S full battery with an optimal protective Li anode exhibited higher capacity retention of 777.4 mAh/g after 100 cycles at 0.1 C as well as better rate performance than the cell with a pure Li anode. This work provides alternative insights to suppress the side reaction for Li‒S batteries with high capacity retention.

Photothermal effect enhance OH−-filling at the interface between the Co3C and electrolyte during the OER, during which the conductivity, light absorption, and heat conversion abilities can be enhanced by Ni alloying.

Mn-based oxides have sparked extensive scientific interest for aqueous Zn-ion batteries due to the rich abundance, plentiful oxidation states, and high output voltage. However, the further development of Mn-based oxides is severely hindered by the rapid capacity decay during cycling. Herein, a two-step metal-organic framework (MOF)-engaged templating strategy has been developed to rationally synthesize heterostructured Mn 2 O 3 -ZnMn 2 O 4 hollow octahedrons (MO-ZMO HOs) for stable zinc ion storage. The distinctive composition and hollow heterostructure endow MO-ZMO HOs with abundant active sites, enhanced electric conductivity, and superior structural stability. By virtue of these advantages, the MO-ZMO HOs electrode shows high reversible capacity, impressive rate performance, and outstanding electrochemical stability. Furthermore, ex situ characterizations reveal that the charge storage of MO-ZMO HOs mainly originates from the highly reversible Zn 2+ insertion/extraction reactions.

Reasonable structure design of an absorber is important to its microwave absorption property. Herein we design a “non-standard” yolk-shelled nanostructure with a morphology mediated between core-shelled and yolk-shelled structures using NixSy sphere as yolk and N, S-codoped carbon as shell (n-NixSy@NSC). The n-NixSy@NSC possesses merits of both core-shelled and yolk-shelled nanostructures, resulted in its excellent microwave absorption performance. The optimal n-NixSy@NSC has a minimal reflection loss of −37.2 dB as the matching thickness is only 1.5 mm, superior to that of the bared NiS2 sphere and previously reported absorbers with similar structure and composition. The experimental results and density functional theory calculations indicate that the enhanced microwave absorption performance of the n-NixSy@NSC is attributed to the increased electrical conductivity and interfacial polarization relaxation as well as the improved impedance matching feature. Our results highlight an efficient strategy for design and fabrication of high-performance microwave absorbers.

Lithium metal is considered to be the best candidate for rechargeable batteries due to its unique advantages. But the instability and the uncontrollable dendrites of the lithium metal anode greatly limit its commercialization. In recent years, in order to obtain stable Li metal anodes, various three-dimensional (3D) current collectors have been proposed. However, for traditional 3D current collectors, its advantages in structure still need to be improved. Therefore, the 3D hierarchical Cu@Ag nanostructure consisting of Ag-decorated Cu nanowires grown on Cu foam as a current collector (denoted as 3D HCu@Ag) is well designed and successfully prepared. Cu nanowires were

The Gibbs free energy of hydrogen adsorption at the edge of molybdenum disulfide (MoS

Because of the increasing demand, high-power, high-rate energy storage devices based on electrode materials have attracted immense attention. However, challenges remain to be addressed to improve the concentration-dependent kinetics of ionic diffusion and understand phase transformation, interfacial reactions, and capacitive behaviors that vary with particle morphology and scanning rates. It is valuable to understand the microscopic origins of ion transport in electrode materials. In this review, we discuss the microscopic transport phenomena and their dependence on ion concentration in the cathode materials, by comparing dozens of well-studied transition metal oxides, sulfides, and phosphates, and in the anode materials, including several carbon species and carbides. We generalize the kinetic effects on the microscopic ionic transport processes from the phenomenological points of view based on the well-studied systems. The dominant kinetic effects on ion diffusion varied with ion concentration, and the pathway- and morphology-dependent diffusion and capacitive behaviors affected by the sizes and boundaries of particles are demonstrated. The important kinetic effects on ion transport by phase transformation, transferred electrons, and water molecules are discussed. The results are expected to shed light on the microscopic limiting factors of charging/discharging rates for developing new intercalation and conversion reaction systems.

The lithium-sulfur (Li-S) battery is regarded as a promising secondary battery. However, constant parasitic reactions between the Li anode and soluble polysulfide (PS) intermediates significantly deteriorate the working Li anode. The rational design to inhibit the parasitic reactions is plagued by the inability to understand and regulate the electrolyte structure of PSs. Herein, the electrolyte structure of PSs with anti-reductive solvent shells was unveiled by molecular dynamics simulations and nuclear magnetic resonance. The reduction resistance of the solvent shell is proven to be a key reason for the decreased reactivity of PSs towards Li. With isopropyl ether (DIPE) as a cosolvent, DIPE molecules tend to distribute in the outer solvent shell due to poor solvating power. Furthermore, DIPE is more stable than conventional ether solvents against Li metal. The reactivity of PSs is suppressed by encapsulating PSs into anti-reductive solvent shells. Consequently, the cycling performance of working Li-S batteries was significantly improved and a pouch cell of 300 Wh kg-1 was demonstrated. The fundamental understanding in this work provides an unprecedented ground to understand the electrolyte structure of PSs and the rational electrolyte design in Li-S batteries.

Considering serious exhausted non-renewable energy resources and electromagnetic radiation pollution issues, it is quite urgent to exploit multifunctional material for realizing both the conversion sustainable energy sources and protection of electromagnetic radiation pollution. Herein, we develop a facile and high-yield preparation route to fabricate a multifunctional material consisted of CoFe alloy nanoparticles encapsulated in nitrogen doped carbon nanotubes arrays grown on both sides of reduced graphene oxide (CoFe@N-CNT/rGO). CoFe@N-CNT/rGO displays excellent properties in the field of rechargeable Zn-air battery and electromagnetic wave absorption. CoFe@N-CNT/rGO shows bifunctional electrocatalytic performances toward oxygen reduction reaction and oxygen evolution reaction, favorably comparable to that of commercial catalysts (Pt/C and IrO2). Furthermore, the assembled liquid and all-solid-state rechargeable Zn-air batteries with CoFe@N-CNT/rGO as air cathode display good charging–discharging performance. As electromagnetic wave absorbing material, CoFe@N-CNT/rGO shows the minimal reflection loss of −33.2 dB at 13.3 GHz, superior to reported carbon-based electromagnetic wave absorbing materials. Based on excellent electromagnetic absorption performance, electromagnetic energy conversion device is designed to realize reasonable utilization and conversion of the absorbed electromagnetic energy. These encouraging results lay a solid foundation for development the multifunctional material and provide an effective strategy for simultaneously solving energy crisis and electromagnetic radiation problems.

Heterostructures with the electric field effect can excite the charge transfer kinetics of materials due to the driving force of the electric field. Herein, we report a new ReS

The lithium sulfur (Li-S) battery is an active research area in the field of energy storage systems, but the shuttle effect is a serious obstacle hindering its application. Herein, a CoSe

Lithium-sulfur (Li-S) batteries are one of the most promising rechargeable storage devices due to the high theoretical energy density. However, the low areal sulfur loading impedes their commercial development. Herein, a 3D free-standing sulfur cathode scaffold is rationally designed and fabricated by coaxially coating polar Ti3C2Tx flakes on sulfur-impregnated carbon cloth (Ti3C2Tx@S/CC) to achieve high loading and high energy density Li-S batteries, in which, the flexible CC substrate with highly porous structure can accommodate large amounts of sulfur and ensure fast electron transfer, while the outer-coated Ti3C2Tx can serve as a polar and conductive protective layer to further promote the conductivity of the whole electrode, achieve physical blocking and chemical anchoring of lithium-polysulfides as well as catalyze their conversion. Due to these advantages, at a sulfur loading of 4 mg cm−2, Li-S cells with Ti3C2Tx@S/CC cathodes can deliver outstanding cycling stability (746.1 mAh g−1 after 200 cycles at 1 C), superb rate performance (866.8 mAh g−1 up to 2 C) and a high specific energy density (564.2 Wh kg−1 after 100 cycles at 0.5 C). More significantly, they also show the commercial potential that can compete with current lithium-ion batteries due to the high areal capacity of 6.7 mAh cm−2 at the increased loading of 8 mg cm−2.

Intrinsic polysulfide shuttling is the most fatal problem with Li-S batteries but it can be suppressed by functionalizing the separators with strong lithium polysulfide absorbents. Carbon nanotube (CNT)-supported MoSe2 nanoflakes with a large interlayer spacing were coated on a commercial polypropylene separator to build an efficient barrier (M/C-PP) to polysulfide shuttling for Li-S batteries. The battery with the separator had initial specific capacities of 1 485 and 880 mAh g−1 at 0.1 and 2 C, respectively, and an excellent long-term cycling stability with a low decay rate of 0.093% per cycle at 0.5 C after 300 cycles. This excellent performance was attributed to the strong adsorption of polysulfides by MoSe2 and the fast charge transport channels provided by the CNTs.

MXenes are well known for their potential application in supercapacitors due to their high-rate intercalation pseudocapacitance and long cyclability. However, the reported low capacity of pristine MXenes hinders their practical application in lithium-ion batteries. In this work, a robust strategy is developed to control the functional groups of Nb2CTx MXene. The capacity of pristine Nb2CTx MXene can be significantly increased by Li+ intercalation and surface modification. The specific capacity of the treated Nb2CTx is up to 448 mAh g−1 at 0.05 A g−1, and at a large current density of 2 A g−1 remains a high reversible capacity retention rate of 75% after an ultra-long cycle of 2000 cycles. These values exceed most of the reported pristine MXenes (including the most studied Ti3C2Tx) and carbon-based materials. It demonstrates that this strategy has great help to improve the electrochemical performance of pristine MXene, and the results enhance the promise of MXenes in the application of lithium-ion batteries.

Cost-effective electrocatalysts are imperative to the large-scale hydrogen evolution reaction. Herein, 1T/2H–MoSe2/Ti3C2 composites are integrated via a hydrothermal method by taking advantage of the tunable phases of MoSe2 and high conductivity of Ti3C2. Consequently, the 1T/2H–MoSe2/Ti3C2 composites exhibit an optimal overpotential of 150 mV at 10 mA cm−2, a low Tafel slope of 90 mV dec−1, and a steady catalytic activity for over 30 h in an alkaline environment. The improved HER performances can be ascribed to the introduction of the Ti3C2 support in a proper proportion, which not only makes the charge transfer process more convenient but also helps the dispersion of MoSe2. Furthermore, the formation of MoSe2/Ti3C2 heterogeneous interfaces and the synergistic effects stemming from the intimate interactions between the individual components ultimately boost the H2O dissociation in the Volmer step. This study indicates that Ti3C2 is an ideal conductive support for improving HER catalytic activity, and paves a new way for other transition metal selenides and MXenes to build highly efficient HER electrocatalysts.

Robust and economical catalysts are imperative to realize the versatile applications of hydrogen. Herein, a 1T-MoS2/N-doped NiSe2 composite was rationally synthesized via a solvothermal method, in which the MoS2 nanosheets have a stable 1T phase structure, and the NiSe2 nanoparticles serve as a cocatalytic support for MoS2. The nonnegligible electronic couplings between NiSe2 and MoS2 could facilitate the optimization of their electronic structure and then improve the hydrogen adsorption. What is more, the nitrogen dopants in the NiSe2 nanoparticles could intensify the intercalation of ammonium ions in the 1T-MoS2 nanosheets, and further enlarge their interlayer spacing, thus the electrolyte could infiltrate into the catalyst more easily and sufficiently. This work provides a new route for rationally designing highly active and low cost hydrogen evolution reaction (HER) catalysts, and enriches the study of transition metal chalcogenides toward HER.

Using density functional theory calculations, we proposed a procedure to screen catalytic hosts for solid and non-solid reactions of Li2S by employing the available functionalized Ti3C2T2 MXenes (T = H, O, F, S, Cl, Se, Te, Br, OH, and NH).

Lightweight and low filler loading of electromagnetic wave absorption materials remain a huge challenge under the premise of strong absorption and broad absorption band. Here, we offer a facile strategy to prepare the ultralight self-supported N-doped reduced graphene oxide aerogels containing pod-like N-doped carbon nanotubes and FeNi@N-doped graphene layer core-shell nanoparticles for high-performance electromagnetic wave absorbing materials. The mass density of the ultralight aerogels is 0.0131 g cm−3, greatly lower than those of activated carbons. With a filling loading of only 10 wt% and the matching thickness of 2.0 mm, the minimal reflection loss of aerogels reaches −39.39 dB at 13.28 GHz. When the matching thickness is smaller than 2.0 mm (1.6–2.0 mm), the minimal reflection loss values of the optimized aerogels can still exceed −20 dB superior to most of reported electromagnetic wave absorption counterparts. Moreover, its maximum effective absorption bandwidth is up to 4.7 GHz at the matching thickness of merely 1.8 mm. The excellent performance of the ultralight bimetal-based aerogels mainly derives from increased dielectric loss, better matching impedance and larger specific surface area. It could be believed our designed ultralight self-supported aerogels can be promising candidates for lightweight absorbers with strong attenuation abilities.

Ti3C2Tx has shown great potential in energy storage filed, but the restacking between Ti3C2Tx nanosheets seriously hampers the maximization of its capacitance. In this study, we rationally designed and synthesized porous Ti3C2Tx assemblies without any additive by introducing ice as spacers using a facile freeze-drying method. The porous Ti3C2Tx assemblies have a three-dimensional network structure, which consists of ultra large Ti3C2Tx lamellar walls and lots of macro- and mesopores. It has been proven that there are more -O groups on the surface of the porous Ti3C2Tx assemblies than the Ti3C2Tx film. The porous Ti3C2Tx assemblies deliver a maximum areal capacitance of 1668 mF/cm2 when the mass loading is 8.4 mg/cm2, an optimized specific capacitance of 247.2 F/g when the mass loading is 5.3 mg/cm2, and 87% capacitance retention over 10000 cycles. The symmetric solid-state supercapacitors based on the porous Ti3C2Tx assemblies show an areal capacitance of 355.8 mF/cm2, the maximum power density of 50 mW/cm2 and an outstanding flexibility under different deformation.

Background Recent evidence of clinical trials highlights that the combination of two noncompetitive anti-EGFR antibodies can benefit patients with several cancers. Previous studies propose that a lattice complex assembled by antibodies and EGFR down-regulates surface EGFR by rapid internalization of the complex. However, there remains a paucity of evidence and understanding on the existence of a lattice complex on cell surface and its cellular processes of internalization. Methods Herein, we used three dimensions structured illumination microscopy to directly observe the actual morphology of the lattice complex formed on Hela cell membrane after noncompetitive anti-EGFR antibody combinations, and we explored the internalized mechanism of noncompetitive antibody combinations by constructing a PIP2 consumption system. Result We observed the lattice complex (length > 1 μm) on the surface of living cell after preincubation with Cetuximab and H11, but combination of Cetuximab and single domain antibody 7D12 fails to assemble the lattice, these results demonstrates the importance of symmetrical structure of conventional antibody for lattice formation. Interestingly, the lattice complex assembles along with cytoskeletal fibers, and its internalization recruits a large amount of PIP2 and triggers the rearrangement of F-actin. Conclusions The above data suggests that large-size lattice complex affects membrane fluidity and dynamic reorganization of cytoskeletal, which may be responsible for its rapid internalization. These new insight will aid in current rational combination design of anti-EGFR antibodies.