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Polymer light-emitting diodes using organic-inorganic heterojunctions have a lot of benefits such as excellent blue-light emission, simple fabrication procedure, and low processing cost. We report on the effect of substrates on the fabrication of poly (9,9-di-noctylfluorenyl-2,7-diyl) or (PFO) thin films and their characterization as a simple light-emitting diode (LED) structure. The structural properties of the thin films were characterized using X-ray Diffraction (XRD). The morphological properties of the thin films were studied using Field Emission Scanning Electron Microscope (FESEM) and Atomic Force Microscopy (AFM). The XRD results demonstrated the formation of amorphous PFO structure, with no presence of the crystalline phase of PFO. The FESEM images showed the formation of cracks due to evaporation from annealing. Optical characteristics were studied using ultravioletvisible (UV-Vis) spectroscopy, Photoluminescence (PL) and reflectance measurements showing the presence of β phase of PFO, important for charge carrier mobility. Thin films deposited on ITO-coated glass, FTO-coated glass and Silicon n-type ( 110) and ( 111) orientation substrates were used to fabricate a simple LED structure. The devices fabricated using Si n-type substrates showed p-n junction characteristics and was a better substrate choice than ITO or FTO coated glass.

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Purpose The purpose of this study is to dope silver (Ag) and fluorine (F) in zinc oxide (ZnO) for the enhancement of electrical and optical properties of ZnO, as previous studies reported the improvement of these properties using individual doping of F and Ag. In this paper, F and Ag co-doped ZnO nanorods were synthesized using a modified hydrothermal method. Design/methodology/approach The hydrothermal method was modified and used for the synthesis of the doped ZnO nanostructures, where stainless autoclave and oven were replaced with the Duran laboratory bottle and water boiler system in the process. The ultraviolet metal-semiconductor-metal photodetector (PD) was fabricated using DC sputtering method. Findings Vertically aligned nanorods images were captured from field emission scanning electron microscopy. XPS analysis confirmed greater spin-orbital interaction in the F and Ag co-doped ZnO sample and revealed the presence of F, Ag, Zn and O in the samples, indicating a successful doping process. X-ray diffraction revealed a hexagonal wurtzite structure with enhanced crystal quality upon co-doping. The bandgap decreased from 3.19 to 3.14 eV upon co-doping because of reduced defects density in the sample. Finally, an ultra-violet PD was fabricated with enhanced sensitivity and response times upon co-doping. Originality/value The low-cost, less energy-consuming Duran laboratory bottle and water boiler system were used as the substitute of expensive, more energy-consuming stainless autoclave and oven in a hydrothermal method for synthesis of F and Ag co-doped ZnO and subsequent fabrication of PD.