Nature Communications publishes Yicheng’s Perovskite Discovery of Stability Reversal
04/2021 - Nature Communications publishes Yicheng’s Perovskite Discovery of Stability Reversal
The renowned scientific journal nature has again published an article on HI-ERN's research work. Dr. Yicheng Zhao has published an article on the “Discovery of temperature-induced stability reversal in perovskites using high-throughput robotic learning”
Stability of perovskite-based photovoltaics remains a topic requiring further attention. Cation engineering influences perovskite stability, with the present-day understanding of the impact of cations based on accelerated ageing tests at higher-than-operating temperatures (e.g. 140 °C). By coupling high-throughput experimentation with machine learning, we discover a weak correlation between high/low-temperature stability with a stability-reversal behavior. At high ageing temperatures, increasing organic cation (e.g. methylammonium) or decreasing inorganic cation (e.g. cesium) in multi-cation perovskites has detrimental impact on photo/thermal-stability; but below 100 °C, the impact is reversed. The underlying mechanism is revealed by calculating the kinetic activation energy in perovskite decomposition. We further identify that incorporating at least 10 mol.% MA and up to 5 mol.% Cs/Rb to maximize the device stability at device-operating temperature (<100°C). We close by demonstrating the methylammonium-containing perovskite solar cells showing negligible efficiency loss compared to its initial efficiency after 1800 hours of working under illumination at 30°C.
The full publication can be here at Nature Communications.