Nanostructured metal oxide semiconductor for photovoltaic applications

The objective of this project is to fabricate a solid state dye sensitized solar cells using the p-type nanometal oxide semiconductor NMO as light absorbing material substituting the conventional organic dye in dye sensitized solar cells (DSSCs). The NMO material serves the purpose as both hole-transporting and photosensitizer in comparison to the usual liquid electrolyte and organic Ru-based dyes in conventional dye-sensitized solar cells (DSSCs). Several solid-state sensitized solar cell structures were investigated and fabricated using this NMO material. The best result obtained so far were devices with NMO2 thin film and TiO2 formed by the Doctor Blade method. The assembled solar cell had the following layers: FTO || NMO2 thin film (spin coat) || TiO2 (APCVD) || Gold-FTO. The results showed a photovoltaic performance with an open circuit voltage (Voc) of around 0.47-0.52 V and short-circuit current density between the 2.09-2.79 µA. NMO2 was believed to possess hole-transporting and photosensitizer purpose at the same time in the solid state SSC structure. The main problem for the solid-state sensitized solar cells fabricated in this project was the low photovoltaic current density and hence low energy conversion efficiency. This problem was believed to be the result of limited interface between 2 mesoporous oxide layers and high charge recombination rate together with high series resistance in the solid state SSC structures we used. Further investigation in the device structures is necessary.Bachelor of Engineerin