In-situ formation of atomic-level Mn-Sn interfacial compounds for enhanced Li-ion integrated anode

Abstract

High capacity nanosized SnO2 Li-ion battery anode can realize the reversible conversion of Sn/Li2O to SnO2. However, the coarsening of Sn particles leads to the incompleteness of this reversible reaction and the rapid decay of the reversible capacity. Here, an atom-level Mn–Sn interfacial composite oxide (MnSnO3) is coated on carbon fibers to form an integrated electrode by a simple in-situ technology. Ultrafine Mn nanocrystals can be uniformly dispersed around Sn nanoparticles with synergistic effect, which can effectively inhibit the coarsening of Sn and promote the high reversibility of SnO2 conversion. In addition to the porous nanostructure and binder-free properties, the prepared integrated anode exhibits initial capacity of 1350 mAh g−1 at 0.05 A g−1 with a high Coulombic efficiency of ~77.4%, superior high-rate capability, and stable long-life of more than 1000 cycles. It is hoped that this design will provide a new idea for the development of high-performance SnO2-based anodes.