Abstract
The increasing global population and demand for clean and sustainable energy has led to increased research on affordable and efficient energy materials. Solar energy materials are one of those promising options. There is increased research on nanostructured metal oxide solar cell as an option for inexpensive, clean and efficient solar cells material. Copper oxide based solar cells are among those attracting interest although the efficiency is still low. This study investigates the numerical modeling and simulation of nanostructured copper oxide (cuprous and cupric oxide) heterojunction solar cells for photovoltaic applications. This is with a view to providing an optimized cell efficiency to aid experimentation and the development of high-efficiency metal oxide solar cells. The inspiration for this investigation is to give premise for experimental design for affordable, non-harmful and efficient alternative material for silicon-based solar cells. This was performed using Solar cells capacitance simulator (SCAPS). The optimization was performed by varying the effect of film thickness and by varying the effect of annealing temperature on properties of the copper oxide solar cells using SCAPS for the numerical analysis. The simulation and optimization was modeled firstly by varying the thickness of both the absorber layer and the buffer layers of Cu2O/TiO2 and CuO/TiO2 pn nanostructured heterojunction solar cells. The input parameter for SCAPS, obtained from literatures includes; temperature of 300K for the film thickness, input power of 1000W/m2 using illumination of AM1.5 lamp, under varying thickness of 0.5 μm to 10.0 μm for the absorber layers (Cu2O and CuO) and 0.05 μm to 6.0 μm for the buffer layer (TiO2) respectively. The simulated solar cell displayed a short-circuit current (Jsc) of 24.0764 A and 26.0516 A, open-circuit voltage (Voc) of 1.0486 V and 0.0435 V, fill factor (FF) of 63.20 % and 71 % with an efficiency (η) of 1.6 % and 8.05 % respectively, at an absorber layer thickness of 500 nm and buffer layer thickness of 50nm. Furthermore, the defect density was obtained for each solar cell. Secondly, the Cu2O/TiO2 and CuO/TiO2 pn nanostructured heterojunction solar cells was numerically analysed under varied annealing condition. Three annealing conditions were considered i.e. the as-deposited (300K), air and nitrogen annealed (423.15 K). Other working conditions include; an illumination of AM 1.5G with a 500 W Xenon lamp representing the sunlight. For this simulation, silver was used as the electrode/contact. The absorber layer thickness was 2000 nm and buffer layer thickness was 200 nm. The simulation report showed that nitrogen...
M.Ing. (Mechanical Engineering Science)