How to get a conversion reaction reversible? Lithium and sodium storage in MoS₂ nanodots

It is shown that lithium as well as sodium can be incorporated into MoS₂ nanodots with astonishing reversibility. For this purpose ultrasmall, single layers of MoS₂ are embedded into carbon fibers via electrospinning. Here the reaction confinement in such a nanodot situation is key for the reversibility. The very same confinement also leads to the substantial lowering of the half-cell voltage which is beneficial in terms of battery function.