• Roberts, Alexander
• Vedarajan, Raman
• Darr, Jawwad A.
• Brett, Djl
• Matsumi, Noriyoshi
• Bauer, Dustin
• Starkey, Cl
• Shearing, Pr

Abstract

Nanoparticles of molybdenum(IV) oxide (MoO2) and a TiO2/MoO(2)nanocomposite were synthesised via a continuous hydrothermal synthesisprocess. Both powders were analysed using XRD, XPS, TEM, and BET andevaluated as active materials in anodes for Li-ion half-cells. Cyclicvoltammetry and galvanostatic charge/discharge measurements were carriedout in the potential window of 0.1 to 3.0 V vs. Li/Li+. Specificcapacities of ca. 350 mAh g(-1) were obtained for both materials at lowspecific currents (0.1 A g(-1)); TiO2/MoO(2 )composite electrodes showedsuperior rate behaviour & stability under cycling (compared to MoO2),with stable specific capacities of ca. 265 mAh g(-1) at a specificcurrent of 0.5 A g(-1) and ca. 150 mAh g(-1) after 350 cycles at aspecific current of 2.5 A g(-1). The improved performance of thecomposite material, compared to MoO2, was attributed to a smallerparticle size, improved stability to volume changes (during cycling),and lower charge transfer resistance during cycling. Li-ion hybridelectrochemical capacitors using TiO2/MoO2 composite anodes andactivated carbon (AC) cathodes were evaluated and showed excellentperformance with an energy density of 44 Wh kg(-1) at a power density of600 W kg(-1).

Topics

• nanoparticle
• nanocomposite
• density
• molybdenum
• Carbon
• energy density
• x-ray diffraction
• x-ray photoelectron spectroscopy
• transmission electron microscopy
• cyclic voltammetry