Disassembly-Reassembly Approach to RuO₂ /Graphene Composites for Ultrahigh Volumetric Capacitance Supercapacitor

A porous, yet compact, RuO₂ /graphene hybrid is successfully prepared by using a disassembly-reassembly strategy, achieving effective and uniform loading of RuO₂ nanoparticles inside compact graphene monolith. The disassembly process ensures the uniform loading of RuO₂ nanoparticles into graphene monolith, while the reassembly process guarantees a high density yet simultaneously unimpeded ion transport channel in the composite. The resulting RuO₂ /graphene hybrid possesses a density of 2.63 g cm^-3 , leading to a record high volumetric capacitance of 1485 F cm^-3 at the current density of 0.1 A g^-1 . When the current density is increased to 20 A g^-1 , it remains a high volumetric capacitance of 1188 F cm^-3 . More importantly, when the single electrode mass loading is increased to 12 mg cm^-2 , it still delivers a high volumetric capacitance of 1415 F cm^-3 at the current density of 0.1 A g^-1 , demonstrating the promise of this disassembly-reassembly approach to create high volumetric performance materials for energy storage applications.