Optimisation of TiO2 and Zn2SnO4 Photoanode Materials for Efficient Dye-Sensitized Solar Cells

Solar energy is a promising technology for energy generation and represents an important candidate with other clean energy technologies as an alternative to fossil energy resources. Research into Dye-sensitized Solar Cells (DSCs) continues in spite of the advent of new solar technologies (such as perovskite solar cells), and decreases in the costs of silicon photovoltaic cells. A number of significant developments have been made in recent times, leading to more diverse research (novel redox mediators, dyes, dye binding mechanisms, and electrolytes, and the development of more efficient photoanode structures). New record efficiencies of DSCs of over 14% and more targeted applications (such as indoor application and power windows for integrated buildings) make it one of the technologies with a broad general interest. In spite of the enormous research that has been conducted to develop efficient photoanode for DSCs, some important drawbacks of photoanode materials have been overlooked and not deeply investigated, such as the effects on DSC performance of amorphous TiO2, different sizes of aggregated mesoporous TiO2 nanoparticles as scattering layers, dye packing density in terms of the isoelectric point, TiO2 paste preparation methods in term of scattering and transparent TiO2 photoanodes, and the different quantum efficiencies of DSCs based on Zn2SnO4 photoanode, used with either ruthenium dye or organic dye in terms of its dye binding mechanism, in comparison with devices based on TiO2.