Topochemical transformation route to atomically thick Co3O4 nanosheets realizing enhanced lithium storage performance.

We first demonstrate the rational design and fabrication of novel atomically thick Co3O4 nanosheets (ATCNs) with a specific facet exposed by topochemical transformation from layered intermediate precursors to optimize energy storage. The eminently enhanced lithium storage performance can be attributed not only to the synergistic advantages of inorganic graphene analogues but also the increase of Co(2+) atoms and charge redistribution for ATCNs, which were first revealed by means of synchrotron radiation X-ray absorption near-edge spectroscopy. This work opens the window for the preparation of non-layered atomically thick nanosheets, which will significantly enrich the species of inorganic graphene analogues and optimize energy storage by reasonable materials design and fabrication.