Fabrication of TiO₂–graphene composite for the enhanced performance of lithium batteries

Abstract

Controllable synthesis of TiO2 nanostructures with conformal and ultrathin graphitic carbon coating is critically desirable for new anode material development for Li-ion batteries. In this study, TiO2 nanoparticles (NPs) synthesized by a facile solgel method were encapsulated in graphene nanosheets (GNS) to improve the electrochemical performance. The encapsulation was facilitated by electrostatic interaction between the positively charged, silane decorated TiO2 surface and the negatively charged graphene oxide. Following encapsulation, the graphene oxide was reduced to create a graphene encapsulated TiO2 nanocomposite. The uniform and individual wrapping of TiO2 nanoparticles by graphene was verified by transmission electron microscopy (TEM) and the measured graphene wrapping thickness agreed well with the calculated thickness based on TGA data and size distribution of TiO2 NPs. The TiO2/graphene anode resulted in an initial capacity of 292.3 mAh·g -1 , a Coulombic efficiency of 100%, and a high specific capacity of 247.4 mAh·g -1 after 100 cycles at a current density of 330 mAh·g -1 (1C). It also demonstrated an outstanding high rate performance with a retained capacity of 158 mAh·g-1 at rate of 20C.

The influence of Graphene quality on performance of a Si/Graphene nanocomposite anode

“…In the first types of samples, graphite flakes were oxidised by the modified Hummer's method, to obtain negatively charged GO precursors for the graphene nanosheets. The formation of the Si/GO nanocomposite, with negatively charged GO and positively charged Si nanoparticles, was enabled by static-electric self-assembly [22]. Then in-situ thermal or chemical reduction was performed to acquire the Si/G nanocomposites.…”

Current Progress of Si/Graphene Nanocomposites for Lithium-Ion Batteries

“…Until the cost of synthesizing graphene becomes more affordable, the use of graphene as additive material seems to be applicable. The improvement of electrochemical performance as a result of adding graphene has been reported in many anode materials such as carbon based graphene composite, metal oxide/graphene composite and alloy with graphene [56][57][58][59].…”

Sulfur resistance of Ce-Mn/TiO 2 catalysts for low-temperature NH 3 –SCR

“…Composite catalysts prepared using these two kinds of active components have favourable low-temperature denitration activity and are stable when introduced to typical catalyst poisons. In addition, the vast surface area, developed pore structure and acid sites of TiO 2 are more conducive to the adsorption of NH 3 and can accelerate the reaction [15][16][17]. Qi et al [18] prepared a non-load-type MnO x -CeO 2 , low-temperature SCR catalyst using co-precipitation.…”