A facile and large-area fabrication method of superhydrophobic self-cleaning polysiloxane/TiO2 nanocomposite films and its dielectric properties

The polysiloxane–TiO 2 nanocomposites were prepared by a solvent casting method in triethanolamine and tetrahydrofuran solvents. The prepared nanocomposites were characterized by X-ray diffraction technique, Fourier transform infrared spectroscopy, and scanning electron microscopy for structural analysis and surface morphology. The amorphous nature of polysiloxane observed in XRD spectra and FTIR spectra shows the characteristic peaks of Si–CH 2 , Si–CH 3 , and Ti–O–Ti, confirming the formation of nanocomposites. The surface morphology shows the nanoparticles are completely embedded in the polysiloxane. Furthermore, the DC conductivity shows the increase in conductivity with the increase in temperature due to tunneling phenomena. The wet contact angle of pure polysiloxane was 78.3° before being exposed to UV light and upon the addition of TiO 2 in PS the WAC increased to 88.2° which clearly indicates that the nanocomposites are superhydrophobic in nature. Among all the nanocomposites of different weight percentages, 0.3 wt% shows the highest DC conductivity of 6 × 10 −5 S/cm. The dielectric spectroscopy study reveals low dielectric constant and tangent loss for 0.3 wt% nanocomposite; as a result it shows the highest conductivity of 1.35 × 10 −4 S/cm. The quality factor confirms that there is a small damping loss for 0.3 wt% of nanocomposites which is favourable for high conductivity.