Publications by authors named "Xuyong Feng"

Metal-organic frameworks (MOFs) present diverse building blocks for high-performance materials across industries, yet their crystallization mechanisms remain incompletely understood due to gaps in nucleation and growth knowledge. In this study, MOF structural evolution is probed using in situ liquid phase transmission electron microscopy (TEM) and cryo-TEM, unveiling a blend of classical and nonclassical pathways involving liquid-liquid phase separation, particle attachment-coalescence, and surface layer deposition. Additionally, ultrafast high-temperature sintering (UHS) is employed to dope ultrasmall Cobalt nanoparticles (Co NPs) uniformly within nitrogen-doped hard carbon nanocages confirmed by 3D electron tomography.

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To enable high performance of all solid-state batteries, a catholyte should demonstrate high ionic conductivity, good compressibility and oxidative stability. Here, a LaCl-based Na superionic conductor (NaZrLaCl) with high ionic conductivity of 2.9 × 10S cm (30 °C), good compressibility and high oxidative potential (3.

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Halide solid-state electrolytes (SSEs) are considered promising candidates for practical applications in all-solid-state batteries (ASSBs), due to their outstanding high voltage stability and compatibility with electrode materials. However, Na halide SSEs suffer from low ionic conductivity and high activation energy, which limit their applications in sodium all-solid-state batteries. Here, sodium yttrium bromide solid-state electrolytes (NaYBr) with a low activation energy of 0.

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In situ polymerization to prepare quasi-solid electrolyte has attracted wide attentions for its advantage in achieving intimate electrode-electrolyte contact and the high process compatibility with current liquid batteries; however, gases can be generated during polymerization process and remained in the final electrolyte, severely impairing the electrolyte uniformity and electrochemical performance. In this work, an in situ polymerized poly(vinylene carbonate)-based quasi-solid electrolyte for high-voltage sodium metal batteries (SMBs) is demonstrated, which contains a novel multifunctional additive N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA). MSTFA as high-efficient plasticizer diminishes residual gases in electrolyte after polymerization; the softer and homogeneous electrolyte enables much faster ionic conduction.

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A lithium metal anode and high nickel ternary cathode are considered viable candidates for high energy density lithium metal batteries (LMBs). However, unstable electrode-electrolyte interfaces and structure degradation of high nickel ternary cathode materials lead to serious capacity decay, consequently hindering their practical applications in LMBs. Herein, we introduced ,-bis(trimethylsilyl) trifluoro acetamide (BTA) as a multifunctional additive for removing trace water and hydrofluoric acid (HF) from the electrolyte and inhibiting corrosive HF from disrupting the electrode-electrolyte interface layers.

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A strategy for modifying the structure of solid-state electrolytes (SSEs) to reduce the cation diffusion activation energy is presented. Two heavily W-doped sodium thioantimonate SSEs, Na W Sb S and Na W Sb S are designed, both exhibiting exceptionally low activation energy and enhanced room temperature (RT) ionic conductivity; 0.09 eV, 24.

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This is the first report of successful potassium metal battery anode cycling with an aluminum-based rather than copper-based current collector. Dendrite-free plating/stripping is achieved through improved electrolyte wetting, employing an aluminum-powder-coated aluminum foil "Al@Al," without any modification of the support surface chemistry or electrolyte additives. The reservoir-free Al@Al half-cell is stable at 1000 cycles (1950 h) at 0.

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A novel and efficient method is demonstrated to improve the electrochemical performance of Li4Ti5O12 and metal-oxide anodes. In contrast to other methods, inexpensive red phosphorus powder is used as a reducing reagent, and the reduction is conducted at a relatively low temperature of 400 °C. This method offers a low cost and effective way for Li4Ti5O12 and metal-oxide anode applications.

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All-solid-state rechargeable batteries embody the promise for high energy density, increased stability, and improved safety. However, their success is impeded by high resistance for mass and charge transfer at electrode-electrolyte interfaces. Li deficiency has been proposed as a major culprit for interfacial resistance, yet experimental evidence is elusive due to the challenges associated with noninvasively probing the Li distribution in solid electrolytes.

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Anionic redox chemistry offers a transformative approach for significantly increasing specific energy capacities of cathodes for rechargeable Li-ion batteries. This study employs operando electron paramagnetic resonance (EPR) to simultaneously monitor the evolution of both transition metal and oxygen redox reactions, as well as their intertwined couplings in LiMnO, LiNiMnO, and LiNiMnCoO cathodes. Reversible O/O redox takes place above 3.

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Bulk doping, surface coating, and size reducing are three strategies for improving the electrochemical properties of Li4Ti5O12 (LTO). In this work, chromium (Cr)-modified LTO with a synergistic effect of bulk doping, surface coating, and size reducing is synthesized by a facile sol-gel method. X-ray diffraction (XRD) and Raman analysis prove that Cr dopes into the LTO bulk lattice, which effectively inhibits the generation of TiO2 impurities.

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Ultrathin Li4Ti5O12 (LTO) nanosheets with ordered microstructures were prepared via a polyether-assisted hydrothermal process. Pluronic P123, a polyether, can impede the growth of Li2TiO3 in the precursor and also act as a structure-directing agent to facilitate the (Li1.81H0.

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A new strategy, namely a high magnetic field-induced method, has been designed to enhance lithium storage properties of MoS2 ultrathin nanosheets. The MoS2 ultrathin nanosheets obtained under 8 T exhibit improved cycling stability at high currents, better rate performance and reduced electrochemical impedance, compared to MoS2 ultrathin nanosheets obtained without a high magnetic field.

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