Single-layered ultrasmall nanoplates of MoS2 embedded in carbon nanofibers with excellent electrochemical performance for lithium and sodium storage.

The preparation and electrochemical storage behavior of MoS2 nanodots--more precisely single-layered ultrasmall nanoplates--embedded in carbon nanowires has been studied. The preparation is achieved by an electrospinning process that can be easily scaled up. The rate performance and cycling stability of both lithium and sodium storage were found to be outstanding. The storage behavior is, moreover, highly exciting from a fundamental point of view, as the differences between the usual storage modes--insertion, conversion, interfacial storage--are beneficially blurred. The restriction to ultrasmall reaction domains allows for an almost diffusion-less and nucleation-free "conversion", thereby resulting in a high capacity and a remarkable cycling performance.