Chapter 5: The Role of Nanostructured Metal Oxides in Hybrid Solar Cells

Nanostructured metal oxides have been implemental to the development of hybrid, organic, and perovskite solar cells due to their wide bandgaps, chemical stability, and tunable electronic properties. This chapter covers the fabrication of nanostructured metal oxides for all applications in hybrid solar cells, including transparent conducting oxides (TCOs), electron/hole blocking layers, and charge transport layers. While each layer plays a unique role in the device operation, they share fundamental properties that can be engineered during their synthesis. Specifically, the role of doping and energy level manipulation, high interfacial surface area for charge separation, and ordered nanostructure arrays for photon manipulation are highlighted. The materials presented here are divided into two main groups, 1D and 2D nanostructures for TCOs and TiO₂ nanocrystals for electron transport layers. The goal of this chapter is to convey a broad range of top-down and bottom-up synthetic methods that are common throughout semiconductor research but have played a vital role in the development of next generation photovoltaics.