چكيده به لاتين
This thesis includes three section as growth state of ZnO nanorods, simulation state of ZnO nanotubes and simulation state of hybrid LEDs using ZnO nanostructures. At first, the effect of zinc oxide nanostructures including (3,0), (4,0), (5,0) and (6,0) zigzag nanotubes with 7-loop nanorods (NR) on hybrid light emitting diodes are investigated by Quantum ESPRESSO software and DFT calculations. The electronic and optical properties of these nanostructures including electronic band structure, density of state, dielectric function, refractive index, absorption coefficient, extinction coefficient, loss coefficient, reflectivity and conductivity coefficient have been investigated. The zinc oxide nanorods have been grown on the ITO / ZnO substrate by chemical bath technique at 85 ° C and 24 mM solution at various times. The structural, electrical and optical properties of these nanorods such as grain size, spectrum of transmittance and absorbance of layers, their strain and stress at different thicknesses have been scrutinized. The average light transparency for different thicknesses after annealing at 400 ° C was between 75 to 79% and absorption occurred at a wavelength of about 250 to 350 nm. In the following, according to some obtained parameters, four LEDs with different layers are simulated in three dimensions using Silvaco software. The structure of four devices are ITO / ZnO NR / MEH-PPV / Al, ITO / ZnO NT / MEH-PPV / Al, ITO / ZnO NR / CH3NH3PbI3 / Al and ITO / ZnO NT / CH3NH3PbI3 / Al. The electrical and optical properties of these devices have been studied and compared. The turn-on voltage of organic light-emitting diodes was larger than that of perovskite light-emitting diodes, but by adding nanotubes to both types of hybrid light-emitting diodes, the amount of turn-on voltage was reduced. In addition, ultraviolet light was observed in the range of 380 nm from all devices, which is in good agreement with the obtained radiative recombination values. Besides, according to the electroluminescence spectrum for devices based on organic semiconductors, a peak in the range of 580 nm is observed, which is related to MEH-PPV. On the other side, the peak located at the wavelength of 800 nm originates from the perovskite semiconductor. Factors such as trap density, defects, logarithmic current-voltage curve and luminance-voltage curve are also studied in this thesis.
