Size-tunable SnO2/Co2SnO4 nanoparticles loaded 3D reduced graphene oxide aerogel architecture as anodes for high performance lithium ion batteries

The size control of active materials among porous carbon architecture remains crucial for the performance of guest/substrate nanohybrids anodes among lithium ion batteries. Herein, we prove that graphene oxide (GO) substrate plays an important role on the size control of active materials and put forward a new strategy to controllably adjust oxides particle size on the 3D reduced graphene oxide aerogel (rGOA) structure. Specifically, the active functional groups on GO substrates can be modulated by controlling the gelation degree of GO, which can then realize an in-situ regulation of the active materials growth process due to Ostwald ripening, and the particle size of them are reduced distinctly. The obtained small-size and fine SnO2/Co2SnO4 loaded rGOA architecture (SnO2/Co2SnO4@rGOA-10) shows improved electrochemical performance, where 3D rGOA structure with large numbers of open pores can not only facilitate charge transfer process but also provide unblocked channels for electrolyte transportation. The decrease of nanoparticles size can also shorten ion transfer route within the bulk phase so as to alleviate the volume expansion as well as improve the kinetics of Li+/e(-) transfer process. The rational strategy of modulating the gelation degree of GO substrates can be extended to synthesize other tunable guest/substrate functional nanohybrids. (C) 2020 Elsevier Ltd. All rights reserved.