One-pot eco-friendly synthesis and supercapacitor applications: Simultaneously oxidation and intercalation of iodinated graphene oxide

Abstract

Graphene halides (graphene derivatives with covalently bonded halogens) are promising two-dimensional structures with intriguing physical and chemical features. Herein we demonstrate the properties of energy storage electrode devices, iodine intercalation onto graphene oxide (I-GO) by utilizing eco-friendly oxidizing agent of NaIO4. The reaction simultaneously executes the effective oxidation and iodine intercalation onto GO using non-metallic approach by sodium metaperiodate at room temperature. We newly introduced an efficient post oxidizing agent of mCPBA here to enrich the epoxide content on graphite surface. The formation of I-GO material characterized by powder X-ray diffraction (PXRD), high resolution transmission electron microscope (HR-TEM) and Fourier transform infra-red spectroscopy (FT-IR). Besides, the chemical composition moieties, structural defects and stability of material further confirmed by X-ray photoelectron spectroscopy (XPS), Raman spectrum and thermogravimetric analysis (TGA). The favourable approach for the surface intercalation of graphite was occurred by iodine and epoxide groups onto the surface graphite. Also, the potential properties of I-GO electrode material investigated by CV, EIS and GCD studies by using 1 M H2SO4 solution as an electrolyte. From above analysis results, I-GO electrode material showed a pseudo capacitance ability. The iodinated graphene had an iodine content of 4.1 wt%. In particular, I-GO electrode material exhibited high specific capacitance of 398.4 F g−1 to three electrode system with the current density of 1 A g−1 and good cycling stability (low capacitance degradation of 6% was up to 3000 cycles). The enhanced specific capacitance is attributed to high ions mobility of iodine and oxygen content in surface of GO. The methodology route offers a facile, toxic less, high producibility and good efficiency within one-pot synthesis process of iodinated graphene oxide towards mainly in supercapacitor applications for lithium-ion batteries.