Laser-Induced Coal-Based Porous Graphene as Anode Toward Advanced Lithium-Ion Battery.

Abstract

Graphene have been considered as the one of the most promising anode materials for the next generation lithium-ion batteries (LIBs) due to its unique properties compared to that of the commercial available graphite anode. However, the tedious preparation process, high cost and easy aggregation of 2D graphene caused by the strong van der Waals interactions among nanosheets affect the high reversible capacity of graphene for LIBs. Herein, a laser-induced strategy employing bituminous coal as a precursor for the preparation of porous graphene-based materials (LIG-B) is reported. LIG-B exhibits a porous foam-like structure and an enlarged interlayer spacing, which is larger than that of graphene with typical AB stacking. As the anode for LIBs, the LIG-B shows a high specific capacity of 400 mAh g^-1 at the current density of 100 mA g^-1, and up to 95.0% of the initial reversible capacity retention after 900 cycles at 100 mA g^-1. This result is higher than that of graphene-based materials such as N-doped rGO (200 mAh g^-1), N-doped Graphene film (150 mAh g^-1), and rGO film (80 mAh g^-1). Most importantly, a high capacity of 220 mAh g^-1 can be maintained at 2000 mA g^-1, indicating its superior rate capability. This work provides a low-cost method to synthesize porous graphene-based materials with fast Li⁺/electronic conductivity for high-performance LIBs.