Oxides@C Core−Shell Nanostructures: One-Pot Synthesis, Rational Conversion, and Li Storage Property

A general and facile one-pot hydrothermal method was developed to prepare oxide@C core−shell nanostructures with carbonaceous polysaccharide shells and oxides (including hydroxides or complex oxides) cores. "Coupled synthesis" or "post-synthesis" approaches can be applied. As-formed particles possess hydrophilic and biocompatible shells and variable cores, thus have promising applications in the areas such as life science or colloid science. The nanostructures can be transformed to a metal@C core/shell structure or hollow carbon structure. Samples were characterized with X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, electron energy loss spectroscopy, and Fourier transform infrared spectroscopy. Electrochemical characterization on calcined SnO2@C nanostructures showed unusual reversible Li storage capacities. This implies the structural optimization might provide new opportunities to enhance the properties of solids in nanoscale.