Semiconducting Metal Oxides for High Performance Perovskite Solar Cells

Revolutionary progress in power conversion efficiency (PCE) of perovskite solar cell from 10% to 22.1% has accompanied significant advances in materials engineering, processing, and device architectures. Increasing fundamental studies unveiled superior intrinsic optoelectronic properties of perovskite materials, while development of customized fabrication processes enabled to full utilization of the advantageous optoelectronic properties. Although such progress has resulted in simplified planar heterojunction architecture, selection of proper selective contacts is still critical for high efficiency and long-term stability. In this chapter, we address the role of the semiconducting metal oxide transporting layer in perovskite solar cell with two major device architectures (n-i-p and p-i-n structure). The role of the semiconducting metal oxide materials in the charge transport process of perovskite solar cell is discussed in details, particularly the historical evolution of device configuration. Finally, future directions for further improvements on issues such as stability, hysteresis, and processability are provided.