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
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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Wang,
a
William F. Stickle
b
and Xiulei Ji*
a
Despite the considerable advances of
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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Areya, Wei Luob, Xiulei Jib,
Chongmin Wanga, Jun Liua,n, Ji-Guang Zhanga,n
aPacific Northwest National
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.
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 report an inverse relationship between measurable porosity values and reversible capacity from sucrose-derived hard carbon as an anode for sodium-ion batteries (SIBs). Materials with low measureable pore volumes and surface areas obtained through N₂ sorption yield higher reversible capacities. Conversely, increasing measurable porosity and specific surface area leads to...
Na-ion batteries are emerging as one of the most promising energy storage technologies, particularly for grid-level applications. Among anode candidate materials, hard carbon is very attractive due to its high capacity and low cost. However, hard carbon anodes often suffer a low first-cycle Coulombic efficiency and fast capacity fading. In...
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., Li, X., Carter, R., Vail, S., ... & Ji, X. (2015).
Low-Surface-Area Hard Carbon Anode for Na-Ion
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...
Converting CO2 to valuable materials is attractive.Herein, we report using simple metallothermic reactions to reduce atmospheric CO2 to dense nanoporous graphene. By using a Zn/Mg mixture as a reductant, the resulted nanoporous graphene exhibits highly desirable properties: high specific surface area of 1900 m2/g, a great conductivity of 1050 S/m...
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@anl.gov (
e.edu (X. Ji).
ually contributed
Abstract
Converting CO2 to valuable materials is attractive