Effects of carbon nanotubes, graphene and titanium suboxides on electrochemical properties of V2Al1-CT ceramic as an anode for lithium-ion batteries

Abstract

Partially-etched V2Al1-xCTz ceramic with the average particle of ∼400 nm was synthesized by etching submicro-sized V2AlC with 40 wt% HF at room temperature (RT) for 48 h and 72 h, respectively. V2Al1-xCTz etched for 72 h has exhibited higher charge-discharge property, with an average reversible discharge capacity of 349.2 mAh·g-1 at 0.1 A g-1 in the 120 cycles for lithium-ion batteries. The electrochemical performances of V2Al1-xCTz could be improved by the addition of carbon nanotubes (CNTs), graphene (GF) and titanium suboxides (Ti4O7) conductive additives, among which CNTs exhibit the best effectiveness with a capacity of ∼460 mAh·g-1 at 0.1 A g-1 in the 140 cycles and a capacity retention of ∼72% at 0.5 A g-1 after 400 cycles.