Porous three-dimensional activated microwave exfoliated graphite oxide as an anode material for lithium ion batteries

摘要

A porous graphene nanosheet, with a Brunauer-Emmett-Teller surface area of up to similar to 3100 m(2) g(-1), is prepared by using chemical activation of microwave exfoliated graphite oxide. The sp(2)-bonded carbon has a continuous three-dimensional network of highly curved atom-thick walls with similar to 1 to 5 nm width pores. As an anode material for lithium ion batteries, it can deliver a reversible specific capacity of similar to 1600 mA h g(-1) at the current of 100 mA g (-1). To understand the Li storage mechanism, porous carbon samples with tunable specific surface area were investigated. The high reversible capacity indicates that the meso-and micropores are the key factor for Li insertion/extraction during discharging and charging. The porous structure and large specific surface area is believed to have contributed to the high performance.