Graphene and heteroatom-doped graphene are potential candidates for high-performance energy storage applications, such as supercapacitors. Herein, we have studied the structure and defect generation in nitrogen-doped reduced graphene oxide (N-rGO), synthesized via pyrolysis of urea in a wide temperature range (600-900 °C). Nitrogen-doped defect densities were analyzed in detail by the deconvolution of the Raman spectrum, where we found the importance of additional I and D'' peaks. I peak is found to be sensitive to the dopant, and D" peak is consistent with the crystallinity, which are further revealed by X-ray photoelectron spectroscopy and X-ray diffraction measurements. Synthesized N-rGO was then investigated for the supercapacitor electrode. N-rGO synthesized at 800 °C, having low crystallinity (crystallite size 3.44 nm), highest degree of reduction (C/O ratio = 23), high specific surface area (152.3 m 2 g −1), and presence of both pseudocapacitive and electric double layer behavior, resulting in highest areal capacitance of 138.4 mF cm −2 , lowest selfdischarge rate, and exceptional capacity retention of 121.7% after 10,000 cycles of charge-discharge. The synthesized electrode material has also been tested for a symmetric supercapacitor cell showing high specific capacitance 66.8 F g −1 in 0.5 M H 2 SO 4 electrolyte. This study is a first of its kind of structural evaluation and Raman characterization of N-rGO for application in supercapacitor cell.

The present work details the development of IrO2 nanoparticles (nps) supported on B-doped reduced graphene oxide as an oxygen evolution reaction (OER) electrocatalyst for electrochemical water splitting. IrO2 on boron-doped...

The current research deals with the study of boron and nitrogen co-doped reduced graphene oxide (BN-rGO) as a support material for iridium oxide (IrO2) nanoparticles for oxygen evolution reaction (OER)...

Hierarchical interconnected nanosheets (HIN) of cobalt manganese nickel sulfide (CoMnNiS) were synthesized on Ni foam by a simple and economical electrodeposition technique for energy storage application. Sulfonated thin nanosheets of Co, Mn and Ni provide stability of chemical activity, surface functionalization and surface reactivity to the electrode. The fabricated electrode shows a specific capacity of 257.4 mA h g À1 (at 2.5 A g À1 ), measured by galvanostatic charging-discharging (GCD). Both diffusion and capacitive mechanisms in the sulfide layer contribute to the high electrical conductivity.Asymmetric devices CoMnNiS/NiCuO and CoMnNiS/CNT (CNT ¼ carbon nanotubes) were fabricated, providing a maximum operating voltage of 1.7 V and 1 V, specific capacity of 20.8 and 50.8 mA h g À1 , and energy density of 8.4 and 6.3 W h kg À1 corresponding to a power density of 985 and 211 W kg À1 , respectively, at a current density of 0.5 and 0.63 A g À1 . These results demonstrate a novel material for application in energy storage devices as an electrode.