Improved Electrochemical Performance of Ni2P2O7 and Mn-doped Ni2P2O7 Electrode Materials for Supercapacitor Applications

摘要

The development of electrode materials for supercapacitors is really progressive and it still poses a huge challenge for researchers in many aspects. Doping of transition metals is indeed effective method because fast interfacial charge transfer kinetics has demonstrated their potential supercapacitive nature. The present work submits the structural, morphological and electrochemical performances of nickel pyrophosphate (Ni2P2O7) and manganese doped nickel pyrophosphate (Mn-Ni2P2O7) thin film electrodes synthesized by chemical bath deposition method. The crystal structure of Ni2P2O7 obtained through X-ray diffraction (XRD) is confirmed to be monoclinic which remains unaltered despite of Mn doping concentration. Morphological studies reveal that crystalline phase of Mn is intimately anchored on the surface of Ni2P2O7 which is beneficial for better charge transfer between transition metal and transition metal phosphates. A specific capacitance value of 603 F/g is obtained for 3 M concentration of Mn doped Ni2P2O7 from galvanostatic charge-discharge curve at current density 1 A/g. This value is noticeably higher than what is obtained for the pure Ni2P2O7 indicating that Mn doping enhances the electrochemical performance of Ni2P2O7 thin films.