Wet Chemical Feasible Synthesis of PPy-Nickel Oxide nanocomposites and their photocatalytic effects on Methylene Blue

In this paper, we report, the synthesis of conducting polymer nanocomposites of nickel oxide polypyrrole (NiO-PPy) doped with dodecyl benzene sulphonic acid for its application as a photocatalyst. In-situ polymerization of the pyrrole technique was employed along with oxidant ammonium persulphate and dodecyl benzene sulphonic acid as a dopant. The nanostructures were synthesized at different concentrations of NiO nanoparticles viz. 0.05 wt.%, 0.1 wt.%, 0.2 wt.% and 0.3 wt.%. The development of nanostructures was explored by Fourier Transform Infrared Spectrophotometer, Field Emission Scanning Electron Microscope, X-ray diffraction spectrometer, and electrical conductivity measurements. FTIR studies revealed a shift in the absorption band when pure PPy and NiO-PPy nanocomposites were studied, exhibiting the substantial interaction between the PPy network and the NiO. FE-SEM analysis demonstrated the consistent distribution of NiO with globular-shaped metal oxide materials in the PPy host template. The XRD studies for pure PPy revealed its amorphous nature while nanocomposites indicated the prominent NiO peaks arising from (111), (200) and (220) planes. The nanocomposites' direct electrical conductivity at room temperature was much higher than pure PPy. It was observed that the electrical conductivity for pure PPy was 0.409×10-5 S/cm while it substantially increased to 4.2×10-5 (S/cm) for 0.3% nanocomposite. The electrical studies revealed that the electrical conductivity goes on increasing with increased NiO concentration and then after a saturation point more PPy encapsulates the NiO and in turn reduces the electrical conductivity. With 50 mg of 0.3% nanocomposite, the photocatalytic degradation of the Methylene-Blue dye was 84.98%.