To improve upon the stability issues MAPbI3 perovskites have with moisture and elevated temperatures, NREL researchers have developed a method to tailor the surface composition of thin-film MAPbI3 perovskites. This novel method involves annealing the surface of a MAPbI3 film that has been treated with an isopropanol solution of MABr to form a surface layer of an I-Br mixed perovskite (MAPbI3-XBrX). This MABr-treated perovskite has been demonstrated through ultraviolet photon spectroscopy (UPS) and current-voltage (I-V) curves to have a shifted valence band position of 30-60-meV with respect to the standard MAPbI3 film and to significantly increase the VOC of MABr-treated films.
This technology is within the Film Efficiency and the Film Stability groups of NREL’s perovskite portfolio. For further information regarding NREL's broader perovskite portfolio, please visit NREL's Perovskite Patent Portfolio website.
The Film Efficiency group consists of film deposition methods, chemistry improvements, and engineering of device layer and architecture to push commercial perovskite device efficiencies to 20% and beyond.
The Film Stability group comprises technologies that improve perovskite devices’ resistance to environmental factors that degrade device performance over time. These technologies include methods of depositing perovskite films, encapsulant coatings, and novel film chemistries.
Please contact Bill Hadley at Bill.Hadley@nrel.gov
Applications and Industries
- Increased VOC
- Shifts valence band position
- Enhanced quality