Porous architectures assembled with ultrathin Cu2O-Mn3O4 hetero-nanosheets vertically anchoring on graphene for high-rate lithium-ion batteries

A series of high-capacity transition metal oxides (TMOs) as anode materials suffer from poor cycling stability and limited rate capability for lithium-ion batteries (LIBs). To deal with these problems, many efforts have been undertaken on designing and fabricating composites based on TMOs. In this study, ultrathin Cu2O-Mn3O4 hetero-nanosheets are in-situ anchored on graphene (CM-GS composites) by combining a facile hydrothermal route and a subsequent calcination, constructing three-dimensional (3D) porous architectures. Investigated as LIB anodes, the porous architectures of CM-GS composites could effectively shorten ion/electron diffusion length and relieve volume changes, and the intimate incorporation between hetero-nanosheets and GS could significantly improve structural stability and electrical conductivity. Thanks to these synergetic advantages, CM-GS electrode delivers a high reversible capacity of 792 mA h g(-1) after 350 cycles at 2500 mA g(-1) with 120% capacity retention, and a reversible capacity up to 739 mAhg(-1) at 5000 mAg(-1) is obtained even after 280 cycles at different current rates, revealing excellent cycling stability and superior rate capability. These results suggest that CM-GS composites are promising anode materials for high-rate LIBs, and this work could provide an efficient strategy for the construction of hetero-structure on conductive substrates with remarkable energy-storage properties for next-generation LIBs. (C) 2019 Elsevier B.V. All rights reserved.