Synthesis of 1,3-dicarbonyl-functionalized reduced graphene oxide/MnO₂ composites and their electrochemical...

A novel 1,3-dicarbonyl-functionalized reduced graphene oxide (rDGO) was prepared by N-(4-aminophenyl)-3-oxobutanamide interacting with the epoxy and carboxyl groups of graphene oxide. The high-performance composite supercapacitor electrode material based on MnO₂ nanoparticles deposited onto the rDGO sheet (DGM) was fabricated by a hydrothermal method. The morphology and microstructure of the composites were characterized by field-emission scanning electron microscopy, transmission electron microscopy, Raman microscopy and X-ray photoelectron spectroscopy. The obtained results indicated that MnO₂ was successfully deposited on rDGO surfaces. The formed composite electrode materials exhibit excellent electrochemical properties. A specific capacitance of 267.4 F g^-1 was obtained at a current density of 0.5 A g^-1 in 1 mol L^-1 H₂SO₄, while maintaining high cycling stability with 97.7% of its initial capacitance after 1000 cycles at a current density of 3 A g^-1. These encouraging results are useful for potential energy storage device applications in high-performance supercapacitors.