A multifunctional graphene oxide-Zn(II)-triazole complex for improved performance of lithium-sulfur battery at low temperature

Abstract

© 2018 Elsevier Ltd Although performance of Li–S batteries with various carbon/sulfur composites has been wildly explored at room temperature, the reports studying the behaviors of Li–S cathodes at low temperature are few. Herein, a novel multifunctional graphene oxide-Zn(II)-triazole complex (denoted as GO-Zn(II)-AmTZ) with excellent property at low temperature(-20 °C) is successfully prepared. In GO-Zn(II)-AmTZ, the metal ions (Zn(II)), amine groups and the N penta-heterocycle are introduced synchronously, leading improvement of Li–S performance at both room and low temperature. As a result of the multifunctional arrangement, GO-Zn(II)-AmTZ cathodes could provide a discharge capacity of 315 mAh g-1(0.5C) after 100 cycles at -20 °C. A capacity of ~520 mAh g-1is achieved over 300 cycles at room temperature with low capacity attenuation rate at current rate of 0.5C. The improved performance is speculated to the contribution of enhanced polysulfide immobilization of GO-Zn(II)-AmTZ modified by the Zn(II), amine groups and the N atoms.