Viable Options for Inorganic HTLs: A Closer Look at CuOx

A major facet of improving perovskite solar cell durability is replacing the commonly organic charge transport layers in favor of more robust, inorganic options. Copper oxide has shown great promise, contributing to some of the highest device efficiencies observed when using inorganic hole transport layers (HTLs). However, only an exploratory level of research has been published using this material. A thorough understanding of this oxide and how it interacts with common perovskite cell components is necessary if CuOx is to be of benefit to the field at large. Here, we present the groundwork for this endeavor, with initial characterization data on variously oxidized phases of CuOx, elucidating parameters and conditions required to create optimal, reproducible films, which will then be coupled with a perovskite absorber.