Au‐Polyaniline Nanocomposite Synthesized Using γ‐Ray Induced Au Nanoparticles

Gold nanoparticles were synthesized radiolatically in a ⁶⁰Co γ‐ray source. The sample solution containing aniline (stabilizer) and chloroauric acid was irradiated to a total dose of 198 kGy. 1∶1 methanol‐water system was used as a solvent. UV‐Visible analysis of the sample confirmed the formation of gold nanoparticles exhibiting a sharp peak at a wavelength of ∼480 nm indicating the zero‐valent state of gold. The solution showed a transition in color from colorless to purple. The stability of the nanosol extended up to a period of 96 h as investigated from the time‐evolved spectra of the solution. 0.5 M concentration of the stabilizer is found to be optimum for yielding stable nanoparticles as revealed from the results obtained by varying the concentration of aniline from 0.05 M to 1.0 M. The nanocomposite of the gold nanoparticles was obtained by oxidative polymerization of aniline in presence of ammonium persulphate. Homogeneity of the nanocomposite was tested with the help of UV–Visible spectroscopy, XRD and TEM analysis. The bare gold nanoparticles showed narrow size distribution of the particles ranging from ∼10–12 nm.

Keywords:

• nanocomposites
• γ‐radiolysis
• UV–visible spectroscopy
• x‐ray diffraction
• transmission electron microscopy

Authors would like to acknowledge CSIR, India and I. I. T. Bombay.