Tuning photophysical properties of PFO conjugated polymer for enhancing polymer light emitting diode performance via addition of SiO2/TiO2 nanocomposite

Tuning photophysical properties of poly(9,9'-di-n-octylfluorenyl-2.7-diyl) (PFO) by addition SiO2/TiO(2 )nanocomposites (STNCs) with different weight ratios is demonstrated. The PFO/STNCs thin films were prepared successfully by solution blending method followed by spin coating technique. The structure properties were investigated via X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM). The optical properties were determined by using UV-Vis and photoluminescence spectropho-tometer, while a Keithley 238 measurement system and HR20 0 0 Ocean Optic Spectrometer were em-ployed to investigate the optoelectronic properties of the PFO/STNCs based polymer light emitting diodes (PLED). The dominant phase in the PFO/STNCs thin films was for the broad hump of PFO and no varia-tion on structure of PFO was observed upon increment the STNCs content. The aggregation of the thin films with higher STNCs content was evidenced theoretically by S-factor calculations and experimentally by FE-SEM images. The extension in the PFO conjugation length upon addition the STNCs, which plays unique role for improvement the performance of PLED devices as proved here by current density and luminance measurements, was evidenced by the systematic red shift of absorption peak of the PFO and vibronic band transitions and extended absorption tail as well. (C)& nbsp;2022 Elsevier B.V. All rights reserved.

Automated summary

The photophysical properties of poly(9,9'-di-n-octylfluorenyl-2,7-diyl) (PFO) were tuned by incorporating SiO2/TiO2 nanocomposites (STNCs) with different weight ratios. The addition of STNCs resulted in aggregation of the PFO/STNCs thin films and an extended conjugation length of PFO, leading to improved performance of polymer light emitting diodes (PLED).