title: Adenine-functionalized Spongy Graphene for Green and High-Performance Supercapacitors.
abstract: A simple method is demonstrated to prepare spongy adenine-functionalized graphene (SFG) as interconnected, porous 3-dimensional (3D) network crinkly sheets. Such 3D network structure provides better contact at the electrode/electrolyte interface and facilitates the charge transfer kinetics. The fabricated SFG was characterized by X-ray diffraction (XRD), FTIR, scanning electron microscopy (FESEM), Raman spectroscopy, thermogravimetric analysis (TGA), UV-vis absorption spectroscopy, and transmission electron microscopy (TEM). The synthesized materials have been evaluated as supercapacitor materials in 0.5 M H2SO4using cyclic voltammetry (CV) at different potential scan rates, and galvanostatic charge/discharge tests at different current densities. The SFG electrodes showed a maximum specific capacitance of 333 F/g at scan rate of 1 mV/s and exhibited excellent cycling retention of 102% after 1000 cycles at 200 mV/s. The energy density was 64.42 Wh/kg with a power density of 599.8 W/kg at 1.0 A/g. Those figures of merit are much higher than those reported for graphene-based materials tested under similar conditions. The observed high performance can be related to the synergistic effects of the spongy structure and the adenine functionalization.
authors.affiliation: Energy Materials Laboratory (EML), School of Sciences and Engineering, The American University in Cairo, New Cairo 11835, Egypt.|Physical Chemistry Department, National Research Centre, Dokki, Giza, Egypt.
authors.forename: Dalia M
authors.initials: DM
authors.lastname: El-Gendy
authors.affiliation: Physical Chemistry Department, National Research Centre, Dokki, Giza, Egypt.
authors.forename: Nabil A Abdel
authors.initials: NA
authors.lastname: Ghany
authors.affiliation: Chemistry Department, Faculty of Science, Ain Shams University, Cairo, Egypt.
authors.forename: E E Foad
authors.initials: EE
authors.lastname: El Sherbini
authors.affiliation: Energy Materials Laboratory (EML), School of Sciences and Engineering, The American University in Cairo, New Cairo 11835, Egypt.
authors.forename: Nageh K
authors.initials: NK
authors.lastname: Allam
mesh_terms: D000225:Adenine / Q000737:chemistry*; D025802:Electric Capacitance; D004566:Electrodes; D004573:Electrolytes; D006108:Graphite / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D013059:Spectrum Analysis, Raman; D014961:X-Ray Diffraction
chemical_list: D004573:Electrolytes; D006108:Graphite; D000225:Adenine