A sponge-like Li4Ti5O12/graphene composite was prepared via sequential hydrothermal process and solid-state heat treatment process for the application to high-power lithium ion batteries. The as-prepared electrode showed outstanding Li electroactivities with a rapid and reversible Li insertion/extraction of up to 10 C-rate (1.75 A/g). It delivered ...
We use confocal mu-Raman spectroscopy to characterize the local microstructure of SiOx particles that are composed of amorphous and crystalline phase and to understand its effects on electrochemical reactions. Particles of bare SiOx (x similar to 1) consist of an inhomogeneous mixture of a-Si and c-Si; some particles mainly have a-Si phase but othe...
This paper reports a novel electrode design for use in electrochemical lithium-ion storage. 3-dimensional patterns of tin dioxide nanowires that are grown directly over current collectors are suggested as electrode frameworks, representing the synergetic combination of nanometer-sized 1-dimensional electrode materials and micrometer-scaled hollow c...
Aliovalently Ce3+-doped Li4Ti5O12 (LTO) is firstly synthesized by a sol-gel method using Ce(CH3COOH)(3) as the dopant and CH3COOLi/(C4H9O)(4)Ti as starting materials. The structure and morphology of Ce3+-doped LTO with various doping level (Li4Ti5-xCexO12; x = 0, 0.05, 0.10, 0.15 and 0.20) are characterized by XRD, EDX, Raman, XPS, SEM and TEM. Pur...
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...
The development of electrode materials capable of delivering high electrochemical performance is a major challenge. Herein, we demonstrate a facile approach for the synthesis of rod-shaped Fe3O4 nanostructures anchored on the reduced graphene oxide (RGO) surface and its application as an active electrode material for supercapacitors. The RGO-Fe3O4...
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...
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...
