Affiliation:
1. Programa de Pós-Graduação em Química-PPGQ - Universidade Federal do Piauí - Teresina
2. Programa de Pós-Graduação em Química – PPGQ - Universidade Estadual do Piauí - Rua: João Cabral
Abstract
Abstract
Porous supercapacitors (SCs) materials are great interesting for energy storage system. Electrolyte contributes for enhancement supercapacitor perform. This paper, iron tungstate mixed oxides electrode was prepared by polymeric precursor method and deposited onto conductor substrate by drop casting heat-treated at 500 ºC for 2 h. The thermal, structural, and morphological characterization was realized by differential scanning calorimetry (DSC), X-ray diffraction (XRD), micro-Raman, emission–scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), respectively. Crystallization process of polymeric resin occurred at 454°C. Synergistic effect of monoclinic FeWO4 and monoclinic Fe2W3O12 phases were confirmed with Fe/W mixed oxides. An irregular shape of condensed spherical-like particles aggregated with rough and porous nanostructures were observed. Neutral electrolytes were employed in electrochemical measurement as lithium nitrate (LiNO3) and sodium sulfate (Na2SO4). SC electrochemical analyses of Fe-W electrode accomplishes a capacitance of 75 F g–1 at 5 mV s–1, energy density of 3.73 Wh kg–1, power density of 582.1 W kg− 1and long-term electrochemical cycling with a capacity retention of 94.04% after 6000 cycles in 0.1 mol L− 1 Na2SO4. Therefore, Fe-W based electrode demonstrates a potential supercapacitor device with excellent stability in a nontoxic aqueous electrolyte.
Publisher
Research Square Platform LLC