November 11, 2015
Journal Article

Interface Promoted Reversible Mg Insertion in Nanostructured Tin-Antimony Alloys

Abstract

This paper demonstrates intermetallic compounds SnSb are highly active materials for reversibly hosting Mg ions. Compared with monometallic Sn and Sb, SnSb alloy exhibited exceptionally high reversible capacity (420 mAh/g), excellent rate capability and good cyclic stability. Mg insertion into pristine SnSb involves an activation process to complete, which induces particle breakdown and results in phase segregation to Sn-rich and Sb-rich phases. Both experimental analysis and DFT simulation suggest that the Sn-rich phase is particularly active and provides most of the capacity whereas the Sb-rich phase is not as active, and the interface between these two phases play a key role in promoting the formation and stabilization of the cubic Sn phase that is more favorable for fast and reversible Mg insertion. We further show that activated SnSb alloy has good compatibility with simple Mg electrolytes. Overall, this work could provide new approaches for designing materials capable of reversible Mg ion insertion and new opportunities for understanding Mg electrochemistry.

Revised: August 11, 2020 | Published: November 11, 2015

Citation

Cheng Y., Y. Shao, L.R. Parent, M.L. Sushko, G. Li, P.V. Sushko, and N.D. Browning, et al. 2015. Interface Promoted Reversible Mg Insertion in Nanostructured Tin-Antimony Alloys. Advanced Materials 27, no. 42:6598-6605. PNNL-SA-108383. doi:10.1002/adma.201502378