Upon lithiation, the active (Ga) and inactive component (Cu) in a binary intermetallic CuGa2 electrode are converted to nanograins ( Ga - Li). The Li.,Ga phase diagram is altered by the presence of Cu nanograins, eloquently demonstrating that the surface energy becomes more important than internal energy in controlling thermodynamics of nanosized m...
Anatase titania nanotube arrayswere fabricated by means of anodization of Ti foil and annealed at 400 degrees C in respective CO and N-2 gases for 3 h. Electrochemical impendence spectroscopy study showed that CO annealed arrays possessed a noticeably lower charge-transfer resistance as compared with arrays annealed in N-2 gas under otherwise the s...
A mesostructured spinel Li4Ti5O12 (LTO)-carbon nanocomposite (denoted as Meso-LTO-C) with large (>15 nm) and uniform pores is simply synthesized via block copolymer self-assembly. Exceptionally high rate capability is then demonstrated for Li-ion battery (LIB) negative electrodes. Polyisoprene-block-poly(ethylene oxide) (PI-b-PEO) with a sp2-hybrid...
We report the comparative investigation on the electrochemical application of mesoporous copper oxide (Cu2O and CuO) microspheres with different surface areas as anode materials in Li-ion batteries. Mesporous Cu2O microspheres with a narrow particle size distribution are synthesized by a hydrothermal method and CuO is obtained by subsequent oxidati...
We report the preparation of high surface area hedgehog-like CuO microspheres by a wet-chemical method and their application in Li-ion batteries used as anode materials. The samples were characterized by Nitrogen adsorption, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, temperature-programmed reduction and therm...
Galvanic replacement reactions provide a simple and versatile route for producing hollow nanostructures with controllable pore structures and compositions. However, these reactions have previously been limited to the chemical transformation of metallic nanostructures. We demonstrated galvanic replacement reactions in metal oxide nanocrystats as wel...
The formation mechanism of LiTi2O4, prepared by a carbon thermal reduction reaction using Li2CO3 and TiO2 (anatase) as starting materials and acetylene black as a reducing agent, was investigated by in situ variable temperature X-ray diffraction and thermal gravimetric analysis/differential scanning calorimetry system. It was found that the cooling...
Destructive gas generation with associated swelling has been the major challenge for the large-scale application of Li4Ti5O12 (LTO)-based lithium-ion batteries (LIBs), especially when the LIBs work at high temperature. Here we report a new kind of Li4Ti5O12-rutile TiO2 (LTO-RTO) hybrid nanowire array electrode that can be cycled at elevated tempera...
Applications of the non-line-of-sight vapor deposition techniques, such as chemical vapor deposition (CVD) and atomic layer deposition (ALD), offer unique opportunities to produce well-defined high surface area current collectors, thin films or various nanostructures of active (ion-storage) materials, protective coatings, solid electrolytes and imp...
Core-shell nano-structured carbon composites have been used as electrode materials in lithium-ion batteries (LIBs) with increasing attention. The large volume swing during lithiation/delithiation processes and poor electronic conductivity are two key issues in the newly-proposed electrode materials, which severely limit their practical application...
