Fabrication of Core-Shell Ni2P@N, P-Co-Doped Carbon/Reduced Graphene Oxide Composite as Anode Material for Lithium- and Sodium-Ion Batteries

Commonly, carbon layer was a suitable choice to enhance the conductivity and reduce the large volume effect of Ni2P nanoparticles (NPs) in electrochemical applications. The doped nitrogen (N) and phosphorous (P) atoms in carbon could further improve its performance. In this paper, core-shell structure Ni2P@N, P-co-doped carbon (Ni2P@N, P-C) NPs were loaded onto reduced graphene oxide nanosheets (GN) to form new composite serial Ni2P@N, P-C/GN, which was designed for the combination of these merits and successfully obtained by two-step method (firstly hydrothermal process and secondly phosphorization process). As anodes for LIBs and SIBs, the responding electrochemical studies showed the Ni2P@N, P-C/GN-0.4 electrode exhibited an outstanding specific capacity of 450 mA h g(-1) at 5 A g(-1) after 2000 cycles in lithium-ion batteries (LIBs) and maintained 110 mA h g(-1) at 2 A g(-1) after 3000 cycles in sodium-ion batteries (SIBs), respectively. These results showed that Ni2P@N, P-C/GN material could be an excellent candidate for energy storage area.