Simple and rapid preparation of CuO film using SILAR process for application as hole-transporting layer in p-i-n perovskite solar cell

Abstract

© 2018 Chulalognkorn University. Copper oxide (CuO) films are considered to be an alternative metal oxide semiconductor for hole-transporting layer application in p-i-n perovskite solar cells due to their unique properties including intrinsic p-type materials and energy band level matching. The films can be synthesized using several methods such as sputtering, solution process and spin-coating processes. However, using the successive ionic layer adsorption and reaction (SILAR) process to prepare a CuO hole-transporting layer in p-i-n perovskite solar cells is still underreported. Thus, this study prepared the SILAR processed CuO films and applied as a hole-transporting layer in p-i-n perovskite solar cells. The results showed that morphology of CuO films is slightly changed when the SILAR cycles is increased, in correlation to the increasing of detected copper element. High optical transmittance in visible light region is found for all conditions, indicating a good transparent film for optoelectronic device likely to solar cells. For solar cell application, a commercial PEDOT:PSS hole-transporting layer was used in a p-i-n perovskite solar cell and compared with the CuO films. The solar cells fabricated with CuO films produced lower performance than that fabricated with commercial PEDOT:PSS. The low performance resulted from the incomplete formation of perovskite films when they are deposited onto CuO films, causing carrier loss due to the recombination effect. However, power conversion efficiency was observed where the solar cell was fabricated with CuO films, which could be attributed to the potential of CuO films as an alternative hole-transporting layer in p-i-n perovskite solar cells. The study indicated that the SILAR method could be an alternative offering a simple, fast, and low cost process for p-i-n perovskite solar cell application.