Hydrothermally synthesized chalcopyrite platelets as electrode material for symmetric supercapacitors
In this work, a novel Chalcopyrite (CuFeS2) platelet like open-pored micro flower structured electrode material was synthesized via one-step hydrothermal method and investigated their electrochemical performance as an electrode material for supercapacitors. First and foremost, the structural, morphological, vibrational, and chemical compositional characteristics of the as prepared CuFeS2 was investigated by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM) with elemental mapping, laser micro Raman, and X-ray photoelectron spectroscopy (XPS), respectively. Subsequently, the electrochemical properties of the CuFeS2 electrode were explored using cyclic voltammetry (CV), galvanostatic charge-discharge (CD), and electrochemical impedance spectroscopy (EIS) studies in 1 M LiOH electrolyte. The cyclic voltammetry and charge-discharge analysis reveal the pseudocapacitive nature of CuFeS2 electrode by obtaining maximum specific capacity of about 26.46 mAh g-1 (specific capacitance of about ~ 95.28 F g-1) at a scan rate of 5 mV s-1 with cycling stability retention of 94.38 % even after 2000 cycles at a discharge current rate of 5 mA. Further, in the view of practical application a symmetric supercapacitor device was fabricated using CuFeS2 electrode and which, delivered a maximum specific capacitance of about 34.18 F g-1 at the current of 1 mA and a maximum energy density of about 4.74 Wh kg-1 with excellent cyclic stability. The acquired results confirmed that CuFeS2 electrode could be a prospective and electrochemically active candidate for next generation supercapacitor.