Integrating nanoscale porous metal oxides into three-dimensional graphene (3DG) with encapsulated structure is a promising route but remains challenging to develop high-performance electrodes for lithium-ion battery. Herein, we design 3DG/metal organic framework composite by an excessive metal-ion-induced combination and spatially confined Ostwald ripening strategy, which can be transformed into 3DG/FeO aerogel with porous FeO nanoframeworks well encapsulated within graphene. The hierarchical structure offers highly interpenetrated porous conductive network and intimate contact between graphene and porous FeO as well as abundant stress buffer nanospace for effective charge transport and robust structural stability during electrochemical processes. The obtained free-standing 3DG/FeO aerogel was directly used as highly flexible anode upon mechanical pressing for lithium-ion battery and showed an ultrahigh capacity of 1129 mAh/g at 0.2 A/g after 130 cycles and outstanding cycling stability with a capacity retention of 98% after 1200 cycles at 5 A/g, which is the best results that have been reported so far. This study offers a promising route to greatly enhance the electrochemical properties of metal oxides and provides suggestive insights for developing high-performance electrode materials for electrochemical energy storage.

The composite Fe7Se8@C encapsulated within 3D-graphene serves as a high-performance flexible anode for LIBs with excellent rate performance.

Facile and controllable integration of metal cyanides (MCs) into three-dimensional graphene (3DG) with advantageous structures is of fundamental importance for the development of superior MC-based electrode materials for electrochemical energy storage and catalysis. Here a facile and versatile spatially-confined Ostwald ripening strategy was developed to synthesize a series of 3DG wrapped MC aerogels with different compositions, size, and structure based on the chemical instability of MC in the reaction system. Remarkably, the integration of Prussian blue (PB) into 3DG, with such unique architecture, largely improves the rate performance and long-term cycling stability of PB as a cathode material for sodium ion batteries.

Three-dimensional (3D) layered tin oxide quantum dots/graphene framework (SnO 2 QDs@GF) were designed through anchoring SnO 2 QD on the graphene surface under the hydrothermal reaction. SnO 2 QDs@GF have a 3D skeleton with a large number of mesopores and ultrasmall SnO 2 QDs with a large surface area. The unique design of this structure improves the specific area and promotes ion transport. The mechanically strong SnO 2 QDs@GF can directly be used as the anode of lithium-ion batteries (LIBs); it displays a high reversible capacity (1300 mA h g −1 at 100 mA g −1 ), excellent rate performance (642 mA h g −1 at 2000 mA g −1 ), and superior cyclic stability (when the current density is 10 A g −1 , the capacity loss is less than 2% after 5000 cycles). This novel synthetic method can further be expanded for the production of other quantum dots/graphene composites with a 3D structure as high-performance electrodes for LIBs.