Nanostructured T-Nb2O5-based composite with reduced graphene oxide for improved performance lithium-ion battery anode

Nb 2 O 5 has attracted much attention in various research filed such as hybrid capacitors, photo/electrocatalysis, and especially Li-ion batteries (LIBs) due to stable structure and high safety. Nevertheless, its low electronic conductivity (~ 3×10 −6 S cm −1 ) degrades Li-storage performance that limits the practical use in LIBs. Here, we present a facile method for synthesis of T-Nb 2 O 5 nanospheres/reduced graphene oxide composites by using niobium oxalate and bituminous coal as raw materials via a solvothermal method and subsequent calcination to enhance the conductivity of Nb 2 O 5 . In this work, the prepared Nb 2 O 5 particles have excellent crystallinity that can be uniformly distributed onto the surface of the rGO layer to form Nb 2 O 5 /rGO composites. The electrochemical properties indicate that Nb 2 O 5 /rGO electrodes exhibit outstanding capacity, excellent reversibility, and superior cycle stability compared to other transition metal oxide-based electrodes. Notably, the initial capacities of the Nb 2 O 5 /rGO electrode at 0.02 A g −1 are 603 and 1104 mAh g −1 , and the capacity still maintained 332 mAh g −1 after 100 cycles at 0.2 A g −1 . Our synthetic approach provides a viable route to produce anode materials in a composite form facilitating nanostructured Nb 2 O 5 with rGO exfoliated from bituminous coal for excellent performance in LIBs.