In the past two years, the highest power conversion efficiency of perovskite absorber (PA)–based photovoltaics has been 20.2%. The PA can be fabricated on flat substrates (for example, ZnO, TiO2, and PEDOT:PSS) using solution processes, which have a low-cost advantage in terms of industry production. In this report, the recent advances of PA-based photovoltaics will be mentioned. Then, the optoelectronic properties of PA, material fabrication, and photovoltaic performance will be discussed. On the other hand, we used scanning electron microscopy, two-dimensional X-ray diffractometer, and photoluminescence spectroscopy to investigate the fundamental properties of CH3NH3PbI3 thin films fabricated with and without toluene washing treatment, which provides an assessment of the development potential of PA-based photovoltaics.
Part of the book: Perovskite Materials
Zinc oxide nanostructure has a wide bandgap energy of 3.37 eV and a large exciton binding energy of 60 meV at room temperature. It is certainly a promising material for photonic devices in the ultraviolet to blue wavelength range. ZnO-related materials are also expected to construct the exciton as well as polariton lasers owing to their excitonic-stimulated emission and laser behavior under optically pumping can be obtained at ambient temperature. Because of the optical losses, including not only nonradiative recombination centers but also traps of excitons, the high quality of ZnO becomes even more imperative in the excitonic lasing processes. In the present chapter, ZnO nanowire structures via a low-pressure vapor-phase deposition and a simple solvothermal method will be presented. The one-dimensional ZnO nanowires could afford a direct conduction pathway to significantly enhance the overall efficiency of the dye-sensitized solar cells. Furthermore, this content will demonstrate how to employ the hierarchical structure of the ZnO nanoparticles, fabricated from sol-gel method, which could promote light scattering, thus, enhancing photon absorption and the overall solar conversion efficiency. The aim of this chapter is to present the correlation between the fundamental properties of ZnO nanostructures and their photovoltaics performances.
Part of the book: Nanostructures