Influence of SiO2 in PANI Matrix as an Electron Transport Layer for OLEDs

Polyaniline-Silicon dioxide (PANI-SiO2) nanocomposites were synthesized via chemically oxidative polymerization process. The formation of PANI, and PANI-SiO2 nanocomposites with their corresponding changes in nanostructured properties were examined by Field Emission Scanning Electron Microscope (FESEM), X-ray Diffraction Spectroscopy (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). From the FESEM analysis it was observed that the PANI have nanofiber like structure whereas SiO2 has granular structure. The agglomeration of PANI nanofibers over the surface of SiO2 revealed the formation of PANI-SiO2 nanocomposites. The UV–Vis. analysis exhibited PANI-SiO2 nanocomposite possess lower band gap and higher absorption intensity than pristine PANI. The PL spectra of PANI and PANI-SiO2 nanocomposite reveals four bands as green bands due to radiative recombination of electron–hole pair. The electrical properties for PANI-SiO2 nanocomposite showed 37% enhancement in current density in comparison to pure PANI. The PANI-SiO2 nanocomposite owed enhanced carrier density and excellent rate of electron–hole recombination that proposed to be suitable candidate for electron transport layer in OLED devices.