Making air-stable all-inorganic perovskite solar cells through dynamic hot-air

On 3rd August 2019 National Renewable Energy Laboratory (NREL) announced a new world record of 25.2% power conversion efficiency (PCE) for the hottest photovoltaic material known as perovskites. The growth in popularity and substantial improvement in the efficiency of perovskites since their discovery in 2009 is demonstrated by over 6000 publications in 2018. Although, the current world record efficiency has been reported for organic-inorganic halide perovskite, all devices were fabricated in controlled inert conditions and organic cations suffer from poor stability. Therefore, replacement of conventional organic cations by inorganic cations is one of the most promising approaches to make thermally stable photovoltaics. However, all-inorganic perovskite solar cells (PSCs) (herein AIPSCs) composition and deposition techniques limit the real-time stability. This article previews the dynamic hot air (DHA) method used for making CsPbI₂Br-based perovskites with improved air-thermal stability using barium (Ba²⁺) alkaline earth metal ion doping. Interestingly, the feasibility of this DHA method toward large area fabrication is also demonstrated.