Preparation of Fe3O4 with high specific surface area and improved capacitance as a supercapacitor

Abstract

Here, we report for the first time a facile ultrasonic synthesis of Fe3O4 nanoparticles using FeCl3 and the organic solvent ethanolamine (ETA). The intermediate of the ETA-Fe(II) complex produces Fe3O4 after hydrolysis and hydrothermal treatment. The moderate reduction of ETA and ultrasound play an important role in the synthesis of superfine Fe3O4 particles with a very high specific surface area (165.05 m(2) g(-1)). The Fe3O4 nanoparticles were characterized by X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM), high-resolution transmission electron microscopy (HRTEM), and ultraviolet-visible absorption spectroscopy (UV-vis). Fe3O4 as an electrode material was fabricated into a supercapacitor and characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge measurements. The as-synthesized Fe3O4 exhibits remarkable pseudocapacitive activities including high specific capacitance (207.7 F g(-1) at 0.4 A g(-1)), good rate capability (90.4 F g(-1) at 10 A g(-1)), and excellent cycling stability (retention 100% after 2000 cycles). This novel synthetic route towards Fe3O4 is a convenient and potential way of producing a secondary energy material which is expected to be applicable in the synthesis of other metal oxide nanoparticles.

Nitrogen-containing carbon microspheres for supercapacitor electrodes

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Tailoring the size and electrochemical performance of Mn3O4 nanoparticles by controlling the precipitation process

“…However, RuO 2 also shows various major disadvantages including expensiveness, toxicity, low abundance, and using of strong acidic electrolyte such as sulfuric acid. Therefore, numerous efforts have been tried to search alternative materials such as Co, Ni, V, Sn, Fe or Mn-based oxides or hydroxides [9][10][11][12][13][14]. Unfortunately, most of them have non EDLC-like behavior including narrow potential window and nonlinear charge dependence, i.e., the batterylike behavior.…”

Carbonized cellulose beads for efficient capacitive energy storage

“…Supercapacitors can be divided into two categories according to their charge storage mechanisms: pseudocapacitors and electrical double layer capacitors (EDLCs) (Wang et al 2012;Winter and Brodd 2004). Pseudocapacitors store electrical energy by fast, reversible faradaic reactions (redox reactions, electrosorption or intercalation) occurring on the electrode materials, typically of metal oxides (Jeong et al 2016;Wang et al 2013a) or conducting polymers (Wang et al 2014(Wang et al , 2015Zhao et al 2017). EDLCs are associated with an electrodepotential-dependent accumulation of electrostatic charge at the interface between the electrolyte and the electrode, typically of carbon (Ghosh and Lee 2012).…”