Employment of SnO2:F@Ni3Sn2/Ni nanoclusters composites as an anode material for lithium-ion batteries

Abstract

Surface modification of SnO2:F particles which obtained from a large-scale electron cyclotron resonance metal organic chemical vapor deposition system was carried out by two consecutive processes: electroless plating processing and annealing. First, Ni film on the SnO2:F and Ni nanoclusters were observed after Ni electrodes plating; the film on the SnO2:F was then converted to Ni3Sn2 after annealing at 800 degrees C under an argon atmosphere. A Ni3Sn2 bimetallic structure formed instead of Ni0 during the annealing process because of the presence of carbon impurities in SnO2:F. The surface-modified Ni3Sn2-covered SnO2:F with Ni nanoclusters (SnO2:F@Ni3Sn2/Ni-nc) was employed as an anode material for lithium-ion batteries. The inactive Ni in Ni3Sn2 acts as a buffer matrix against the Sn active material during the charge-discharge reactions, enhancing the electrochemical performance. The Ni nanoclusters in SnO2:F@Ni3Sn2/Ni-nc perform dual functions: they not only improve the conductivity as the contacting media, but also increase the initial columbic efficiency by the decomposition of Li2O-an electrochemically irreversible material. An outstanding reversible capacity of 600.69 mA h g(-1) and a coulombic efficiency of 99.23% for SnO2:F@Ni3Sn2/Ni-nc were observed at the 350th cycle under 200 mA g(-1) in the our experimental range. (C) 2016 Elsevier B.V. All rights reserved.