Cheverl phase Mo6Te8 nanoparticles as new anode materials for lithium-ion batteries

Abstract

Lithium-ion batteries have become increasingly indispensable as a kind of energy conversion and storage device. Cheverl phase materials show potential advantages over transition metal chalcogenides in lithium-ion batteries, owing to their high three-dimensional open frameworks and good tolerance to a large current. Herein, Chevrel phase Mo6Te8 has been synthesized by high-temperature solid-phase reaction and modified with dopamine, resulting in Carbon and Nitrogen atoms anchored on the Mo6Te8 surface. During the C/N doping process, due to lattice gap and vacancy defects, C/N itself is adsorbed in the vacancy or lattice gap, resulting in lattice expansion, which makes the process of lithium ion deintercalation smoother. Compared with the original Mo6Te8, the specific capacity and conductivity of the composite Mo6Te8@C/N have significantly improved. With a maximum specific capacity close to 812 mAh g−1 at a current density of 0.1 A g−1 and a maximum capacity close to 436 mAh g−1 at a high current density of 1 A g−1, the excellent conductivity of Mo6Te8@C/N contributes to the diffusion of Li+, and the increased active site improves the efficiency of electron transfer. The direct comparison between MoTe2 and Mo6Te8@C/N clearly supports the advantages of Chevrel phase materials in batteries.