Microwave-assisted synthesis of graphene nanocomposites: recent developments on lithium-ion batteries

Abstract

Lithium ion battery (LIB) is a popular power source for various portable mobile devices and even electrical vehicles. Graphene-based composites are important electrodes for LIBs due to their high-capacity, long cycle life, and impressive high-rate capability. Microwave-assisted synthesis is a promising approach to prepare graphene-based composites owing to its fast, energy-efficient features. By varying microwave irradiation conditions, surface functionality and morphology control can be tuned for either graphene or the introduced secondary phase in the graphene-based composites. When used for LIBs, the graphene-based composites can offer a variety of merits for the improved electrochemical properties such as facilitated lithium diffusion/ storage and the increased mechanical stability of the electrodes during repetitive cycling. This article reviews the recent progress of microwave-assisted synthesis of graphene-based electrodes and their applications for LIBs. Graphene-supported transitional metal oxides anodes (Li-storage conversion mechanism), tin/germanium/silicon based anodes (lithium alloy mechanism), metal sulfides (conversion or lithium alloy mechanism), lithium-titanium-oxide-based anodes (lithium insertion mechanism), and graphene-decorated lithium iron phosphate cathodes are reviewed with more emphasis because these materials have attracted significant research concerns. The effect of microwave irradiation and the resultant structure and size control of graphene-based composites on their electrochemical properties is also elucidated.