Preparation and characterization of nickle dispersed polyaniline matrix

Abstract

Electronically conducting polyaniline was made magnetic in nature by incorporating magnetic metals into its matrix. In this connection, metallic Ni particles were successfully dispersed onto polyaniline matrix by a simple one step electrochemical method. Ni particles as deposited onto the polymer (PANI/Ni) seem to have much smaller size compared to that deposited on the bare Pt. Size of the Ni deposits was found to be influenced by the electrolytic bath compositions and potential sweep rate. Polyaniline/Ni matrix thus prepared was further characterized by a wide range of experimental techniques including optical microscopy, scanning electron microscopy, IR spectroscopy, X-ray diffraction, solid-state d.c. conductance . and magnetic susceptibility measurements. Polyaniline/Ni film matrix as prepared was found to have excellent electroactivity. The stability and durability of PANI/Ni film in repeated oxidation/reduction cycle and its degradation at high positive potential were also examined. The result based on cyclic voltammogram suggests a better electrochemical stability of the polyaniline/Ni film electrode relative to the bulk polyaniline film. Deposition of Ni both on a bare Pt and polyaniline surfaces were performed by varying the electrolytic bath composition and potential sweep rate. The bath composition employed are: (i) O.IM Ni-II salt solution, (ii) O.IM Ni-ll salt + O.IM boric acid and (iii) O.IM Ni-ll salt + O.IM boric acid + 10-4 H2S04 solutions. Sweeping potential rates of 50 and 200 mV sec.1 were employed. Under all the experimental conditions employed, Ni was found to be casted both on Pt and polyaniline substrates. An energy dispersed X-ray analysis showed a Ni content of approximately 4.26% in the polyaniline matrix.