Synthesis and augmented optical characteristics of PEO–PVA–SrTiO₃–NiO hybrid nanocomposites for optoelectronics and antibacterial applications

Recently, polymer composite materials have done well in a wide range of technological applications, such as renewable energy, biomedical applications, optoelectronic devices… etc. In this study, the researchers study structural and optical properties of PEO–PVA blend doped with different weight percentages of SrTiO₃–NiO NPs (0, 1, 2, 3 and 4) wt% which were obtained via the solution casting method. Scanning electron microscopy results show that the grain aggregates as the concentration of nanoparticles increases and surface morphology of the NCs with many groupings or pieces randomly doled out on the surface coherent and homogeneous. Optical microscope images show that the additive distribution of NPs in the blend was homogeneous and the nanoparticles create a continuous network inside the polymers. The transmittance of PEO–PVA–SrTiO₃–NiO NCs is decreased from 46 to 21% when the concentrations of SrTiO₃–NiO NPs reached 4%.The allowed and forbidden indirect energy gap of this NCs decreased from 3.6 to 2.5 (eV), and from 3.8 to 2.5 (eV), respectively, when increasing the weight percentages of NPsto 4 wt%. This behavior is useful for optoelectronics, solar cells, and diodes fields with low cost and light weight. The absorption, absorption coefficient, extinction coefficient, refractive index, real and imaginary dielectric constants and optical conductivity of PEO–PVA blend increases with increasing the concentration of SrTiO₃–NiO NPs. The inhibition zone values of E. coli and S. aureusmicro-organisms increased by increasing the SrTiO₃–NiO NPs ratio in PEO–PVA to 28 and 24 mm. Thus, these results indicate the applicability and potential of the nanocomposites for use in optoelectronics and medical applications.