A robust solvent deficient route synthesis of mesoporous Fe2O3 nanoparticles as supercapacitor electrode material with improved capacitive performance

Here, we report a robust synthesis of iron oxide nanoparticles using a facile solvent deficient approach. The process involves only 2-3 simple steps, where, a hydrated ferric nitrate nonahydrate (Fe(NO3)(3)center dot 9H(2)O) salt is grinded with the ammonium bicarbonate (NH4HCO3) for 10 min without addition of any solvent to obtain a precursor. To form Fe2O3 nanoparticles this precursor was further annealed at 350 degrees C for 2 h in two different stages, (i) as prepared untreated and (ii) after rinsing by using deionized water. Single phase Fe2O3 particles formation was confirmed from X-ray diffraction pattern, Fourier transform infrared spectra and Raman spectra analysis. Scanning electron micrograph images shows, distinct morphology is achieved for two different samples. The N-2 adsorption-desorption measurement confirms the mesoporous nature with specific surface area of 40 and 85 m(2)g(-1) for samples obtained from untreated and rinsed precursors. Further, electrochemical performance determined using cyclic voltammetry, chronopotentiometry and electrochemical impedance spectroscopy shows the maximum improved specific capacitance for untreated and rinsed samples is 360 and 469 Fg(-1) at 2 mVs(-1) scan rate with a very less electrochemical series resistance of 4.12 Omega and 2.34 Omega, respectively. The maximum energy density of 12.38 and 18.32 Whkg(-1) and power density of 2531 and 2702 Wkg(-1) is achieved for Fe2O3 samples obtained from untreated and rinsed precursors. Also, it shows cyclic stability of 78% and 84% upto 2000 cycles for Fe2O3 obtained from untreated and rinsed precursors, respectively. (C) 2017 Elsevier B.V. All rights reserved.