Publications by authors named "Ajuan Hu"

Lithium-oxygen (Li-O) batteries, renowned for their high theoretical energy density, have garnered significant interest as prime candidates for future electric device development. However, their actual capacity is often unsatisfactory due to the passivation of active sites by solid-phase discharge products. Optimizing the growth and storage of these products is a crucial step in advancing Li-O batteries.

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Article Synopsis
  • The text discusses the limitations of traditional PEO-based polymer electrolytes for lithium batteries, particularly their low ion conductivity at room temperature, which hampers their commercial application.
  • Researchers developed a new cross-linked polymer with a 3D mesh structure that enhances the dissolution of LiTFSI salt and achieves a higher ionic conductivity of 0.49 mS/cm at room temperature.
  • This new intrinsic polymer electrolyte (IPE) demonstrates strong performance and stability in lithium batteries, achieving over 2,000 hours of stable cycles with excellent capacity retention, indicating its potential for industrial adoption in all-solid-state lithium batteries.
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The usage of flame retardants in flammable polymers has been an effective way to protect both lives and material goods from accidental fires. Phosphorus flame retardants have the potential to be follow-on flame retardants after halogenated variants, because of their low toxicity, high efficiency and compatibility. Recently, the emerging allotrope of phosphorus, two-dimensional black phosphorus, as a flame retardant has been developed.

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Solid-state lithium metal batteries are hindered from practical applications by insufficient room-temperature ionic conductivity and poor electrode/electrolyte interfaces. Herein, we designed and synthesized a high ionic conductivity metal-organic-framework-based composite solid electrolyte (MCSE) with the synergy of high DN value ligands from Uio66-NH and succinonitrile (SN). XPS and FTIR reveal that the amino group (-NH) of Uio66-NH and the cyano group (-C≡N) of SN have a stronger solvated coordination with Li, which can promote the dissociation of crystalline LiTFSI, achieving an ionic conductivity of 9.

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As a holy grail in electrochemistry, both high-power and high-energy electrochemical energy storage system (EES) has always been a pursued dream. To simultaneously achieve the "both-high" EES, a rational design of structure and composition for storage materials with characteristics of battery-type and capacitor-type storage is crucial. Herein, fluorine-nitrogen co-implanted carbon tubes (FNCT) have been designed, in which plentiful active sites and expanded interlayer space have been created benefiting from the heteroatom engineering and the fluorine-nitrogen synergistic effect, thus the above two-type storage mechanism can get an optimal balance in the FNCT.

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The urgent demand for high energy and safety storage devices is pushing the development of lithium metal batteries. However, unstable solid electrolyte interface (SEI) formation and uncontrollable lithium dendrite growth are still huge challenges for the practical use of lithium metal batteries. Herein, a composite polymer electrolyte (CPE) endowed with designated ion channels is fabricated by constructing nanoscale Uio66-NH layer, which has uniformly distributed pore structure to regulate reversible Li plating/stripping in lithium metal batteries.

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Article Synopsis
  • * A new electrolyte solvent, 1,1,3,3-tetramethylurea (TMU), allows for a faster one-electron oxidation pathway, resulting in significantly lower charge overpotential.
  • * TMU also shows good stability, allowing lithium-oxygen batteries to last over 135 cycles, which is four times longer than those using tetraglyme.
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Because of their high theoretical energy density and low cost, lithium-sulfur (Li-S) batteries are promising next-generation energy storage devices. The electrochemical performance of Li-S batteries largely depends on the efficient reversible conversion of Li polysulfides to LiS in discharge and to elemental S during charging. Here, we report on our discovery that monodisperse cobalt atoms embedded in nitrogen-doped graphene (Co-N/G) can trigger the surface-mediated reaction of Li polysulfides.

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Lithium-sulfur batteries are widely seen as a promising next-generation energy-storage system owing to their ultrahigh energy density. Although extensive research efforts have tackled poor cycling performance and self-discharge, battery stability has been improved at the expense of energy density. We have developed an interlayer consisting of two-layer chemical vapor deposition (CVD)-grown graphene supported by a conventional polypropylene (PP) separator.

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