Nickel decorated melamine-formaldehyde resin/polyaniline composites for high specific capacitance

Abstract

Nickel decorated electro-conducting melamine-formaldehyde resin (MFR) composites were prepared in two steps. In the first step micron-sized electro-conducting MFR/polyaniline (PAni) composite particles were prepared by in situ seeded chemical oxidative polymerization of aniline in presence of mesoporous MFR seed particles. Then surface of MFR/PAni composite particles were decorated/doped with Ni particles via in situ chemical reduction of Ni(II) salt. The size, chemical composition and magnetic properties of the prepared composite particles named as MFR/PAni/Ni were analyzed by scanning election microscope (SEM), transmission electron microscope (TEM), Brunauer–Emmett–Teller (BET) surface analysis, Fourier Transform IR (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analyzer (TGA) and vibrating sample magnetometer (VSM). The results suggested that surface of MFR/PAni composite particles are best doped/decorated with Ni particles when MFR/PAni to Ni weight ratio was 1/0.1. An increase in Ni amount resulted in higher agglomeration and produced some free Ni particles. MFR/PAni/Ni composite particles possessed paramagnetic characteristics. The electrochemical/capacitive performance of MFR/PAni/Ni composite materials was evaluated by cyclic voltammetry (CV). Surface decoration/doping of MFR/PAni composite particles with increasing amount of Ni particles improved the specific capacitance value, suitable for application in supercapacitor.