Sodium-ion batteries are emerging as a highly promising technology for large-scale energy
storage applications. However, it remains a significant challenge to develop an anode with
superior long-term cycling stability and high-rate capability. Here we demonstrate that the
Na⁺ intercalation pseudocapacitance in TiO₂/graphene nanocomposites enables high-rate
capability and long cycle life...
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pseudocapacitance in graphene-coupled titanium
oxide enabling ultra-fast sodium storage and long-term cycling
Chen
We, for the first time, employ magnesiothermic reaction to convert microwave-irradiated graphite oxide to pure graphene. The magnesiothermic reaction raises the carbon to oxygen atomic ratio from 22.2 to 165.7 and maintains a high surface area. The new strategy demonstrates an efficient method for obtaining highly pure graphene materials.
Despite the considerable advances of deposition technologies, it remains a significant challenge to form conformal deposition on surface of nanoporous carbons. Here, we introduce a new ambient hydrolysis deposition method that employs and controls pre-adsorbed water vapor on nanoporous carbons to define the deposition of TiO₂. We converted the deposited...
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TiN/Carbon Capacitive Electrode
Xingfeng Wang,
# a
Vadivukarasi Raju,
# a
Wei Luo
,
a
Bao
We introduce a novel ambient hydrolysis deposition (AHD) methodology that, for the first time, employs sequential water adsorption followed by a hydrolysis reaction to infiltrate tiny SnO2₂ particles inside nanopores of mesoporous carbon in a conformal and controllable manner. The empty space in the SnO2₂/C composites can be adjusted by...
We demonstrate a novel synthetic route to fabricate a one-dimensional
peapod-like Sb@C structure with disperse Sb
submicron-particles encapsulated in carbon submicron-tubes.
The synthetic route may well serve as a general methodology
for fabricating carbon/metallic fine structures by thermally
reducing their carbon-coated metal oxide composites.
We, for the first time, demonstrate that orthorhombic V₂O₅ can exhibit superior electrochemical performance in sodium ion batteries when uniformly coated inside nanoporous carbon. The encapsulated V₂O₅ shows a specific capacity as high as 276 mAh/g, while the whole nanocomposite exhibits a capacity of 170 mAh/g. The V₂O₅/C composite was...
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,† Xingfeng Wang,† William F.
Stickle,‡ Galen D. Stucky§ and Xiulei Ji*†
†
Department of Chemistry, Oregon
Porous silicon prepared by low-cost and scalable magnesiothermic reactions is a promising anode material for Li-ion batteries; yet, retaining good cycling stability for such materials in electrodes of practical loading remains a challenge. Here, we engineered the nanoporous silicon from a modified magnesiothermic reaction by controlled surface oxidization forming a...
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. Chen, D.H. Wang, Adv. Energy
Mater. 3 (2013) 295–300.
[30] H.G. Zhang, P.V. Braun, Nano Lett. 12 (2012
Magnesiothermic reduction can directly convert SiO₂ into Si nanostructures. Despite intense efforts, efficient fabrication of highly nanoporous silicon by Mg still remains a significant challenge due to the exothermic reaction nature. By employing table salt (NaCl) as a heat scavenger for the magnesiothermic reduction, we demonstrate an effective route to...
Electrochemical double-layer capacitors exhibit high power and long cycle life but have low specific energy compared with batteries, limiting applications. Redox-enhanced capacitors increase specific energy by using redox-active electrolytes that are oxidized at the positive electrode and reduced at the negative electrode during charging. Here we report characteristics of several...
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-82
(1981).
2. Yang X., Cheng C., Wang Y., Qiu L., Li D. Liquid-mediated dense integration of
Electrochemical double-layer capacitors exhibit high power and long cycle life but have low specific energy compared with batteries, limiting applications. Redox-enhanced capacitors increase specific energy by using redox-active electrolytes that are oxidized at the positive electrode and reduced at the negative electrode during charging. Here we report characteristics of several...
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electrochemical capacitors with
high specific energies and slow self-discharge
Chun, S. E., Evanko, B., Wang, X