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Using a three-dimensional (3D) Li-ion conducting ceramic network, such as Li7La3Zr2O12 (LLZO) garnet-type oxide conductor, has proved to be a promising strategy to form continuous Li ion transfer paths in a polymer-based composite. However, the 3D network produced by brittle ceramic conductor nanofibers fails to provide sufficient mechanical adaptability. In this manuscript, we reported a new 3D ion-conducting network, which is synthesized from highly loaded LLZO nanoparticles reinforced conducting polymer nanofibers, by creating a lightweight continuous and interconnected LLZO-enhanced 3D network to outperform conducting heavy and brittle ceramic nanofibers to offer a new design principle of composite electrolyte membrane featuring all-round properties in mechanical robustness, structural flexibility, high ionic conductivity, lightweight, and high surface area. This composite-nanofiber design overcomes the issues of using ceramic-only nanoparticles, nanowires, or nanofibers in polymer composite electrolyte, and our work can be considered as a new generation of composite electrolyte membrane in composite electrolyte development.

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A tin antimony alloy-filled porous carbon nanofiber composite prepared by electrospinning exhibited high capacity and stable rate capability for use as an anode material in next-generation sodium-ion batteries.

Developing a high-performance nonprecious metal electrocatalyst for water splitting is a strong demand for the largescale application of electrochemical H 2 production. In this work, we design a facile and scalable strategy to activate titanium metal for the hydrogen evolution reaction (HER) in alkaline media through incorporating hydrogen into the α-Ti crystal lattice by H 2 plasma bombardment. Benefiting from the accelerated charge transfer and enlarged electrochemical surface area after H 2 plasma treatment, the H-incorporated Ti shows remarkably enhanced HER activity with a much lower overpotential at −10 mA cm −2 by 276 mV when compared to the pristine Ti. It is revealed that the retention of the incorporated H(D) atoms in the Ti crystal lattice during HER accounts for the durable feature of the catalyst. Density functional theory calculations demonstrate the effectiveness of hydrogen incorporation in tuning the adsorption energy of reaction species via charge redistribution. Our work offers a novel route to activate titanium or other metals by H incorporation through a controllable H 2 plasma treatment to tune the electronic structure for water splitting reactions.

Novel silicon/silica/carbon (Si/SiO 2 /C) composite nanofibers were synthesized by electrospinning and subsequent heat-treatment of a mixture of Si nanoparticles, sol-gel tetraethyl orthosilicate solution, and aqueous polyvinyl alcohol solution. These Si/SiO 2 /C nanofiber composites were also coated with amorphous carbon by chemical vapor deposition (CVD) technique. The CVD carboncoated nanofiber composites formed freestanding, conductive nonwoven mats that were used directly as binder-free anodes in lithium-ion batteries. Results indicated that the SiO 2 component of the composite anodes provided sufficient buffer function to accommodate the volume expansion of the Si nanoparticles and the CVD amorphous carbon coating helped maintain the Si nanoparticles within the carbon nanofiber matrix during repetitive charging and discharging processes. Electrochemical performance tests showed that the capacity retention of CVD carbon-coated Si/SiO 2 /C nanofiber composites was greater than 91% and the corresponding coulombic efficiency was 97.4% at the 50th cycle. Electrochemical energy storage has been demonstrated as one of the most promising technologies for different applications such as grid storage, electric vehicles, and portable electronic devices.1-3 Because of their superior properties, including high energy density, good cycle life and good power performance, lithium-ion batteries are considered as the most preferred rechargeable battery technology in recent years.4-6 The development of high-capacity electrode materials for high-energy lithium-ion batteries is critically important for technological improvements on portable electronics and electric vehicles that use lithium-ion batteries as the power source. 7,8 Current commercial lithium-ion batteries use graphitic materials in the anode. However, graphitic anode materials cannot meet the capacity requirements of future portable electronics because of their low specific capacity of 372 mAh g −1 . 7,9,10 Lithium storage capacities of alloy-type anodes, such as silicon (Si), tin, germanium, etc., are much higher than that of commercially-used intercalation-type graphite anodes. Among all alloy-type anodes, Si has the highest theoretical capacity of 4200 mAh g −1 , making it the best candidate for next-generation high-energy lithium-ion batteries.11-13 However, the insertion of lithium ions into Si during cycling induces large volumetric change (up to 400%), which causes intense pulverization of active Si material, loss of electrical contact between Si and carbon conductor, and unstable solid electrolyte interphase (SEI) formation on the Si surface.14-16 These drawbacks bring together the performance degradation of active Si material during repetitive lithiation and de-lithiation processes. 17,18 To eliminate the aforementioned drawbacks, Si-based composite anodes have been widely investigated. Among them, Si/carbon (Si/C) composites have drawn great attention, which can potentially combine the advantageous properties of Si (high capacity) and C (excellent electr...