Hierarchical modulation of NiSe2 nanosheets/nanodendrites by phase engineering on N-doped 3D porous graphene as self-supporting anode for superior lithium ion batteries

In order to deal with the shortage of fossil fuel reserves and environmental pollution, lithium-ion batteries (LIBs) have been widely studied as a new type of sustainable green energy device. In the work, the NiSe2 nanosheets/ nanodendrites hierarchical material with two phases is deposited on the framework of three-dimensional nitrogen-doped graphene (NPG) through the hydrothermal method to construct a self-supporting anode for LIBs. The NPG has ultralow self-weight as well as excellent electrical conductivity, which inhibits the agglomeration during the growth of active materials. Furthermore, the unique hierarchical NiSe2 active material also relieves its structural damage during the charge and discharge process. As a result, the NiSe2 combined with NPG (NiSe2@NPG) expresses specific capacities of 860 mAh/g and 568 mAh/g at current densities of 0.2 A/g and 3.2 A/g, respectively, making it a promising lithium-ion battery anode material.