Morphology-dependent performance of nanostructured Ni3S2/Ni anode electrodes for high performance sodium ion batteries

Transition metal sulfides have been treated as promising materials for lithium-ion battery, and recently more and more attention has been paid to its applications in sodium-ion batteries. In our context, three Ni3S2 nanostructures directly grown on Ni foam were successfully designed using a facile hydrothermal method. The influences of the morphology on the performance evolution for sodium-ion batteries were studied in detail. As a result, it was found that the initial drop, gradual increase, convex type decline and concave type decline in the performance evolutions were mainly controlled by R-ct, R-sf, pulverization, and internal stress, respectively. More importantly, our results indicated that the clustered network-like structure was beneficial for the cycling and rate performance, while the rod-like structure was suitable for the cyclic stability of these electrodes. (C) 2016 Elsevier Ltd. All rights reserved.