P‐256: Late‐News Poster: Research on the High‐Temperature Lifetime Stability of Tandem Devices

We found that the CGL of our tandem devices is not stable enough. n‐dopant and p‐dopant may react at the interface of n‐CGL and p‐CGL, which will cause lifetime suddenly drops accompanied by a rapid increase in voltage under ultra‐high temperature conditions. Therefore, we have developed a new CGL structure which makes our tandem OLED can operate stably at 110°C with a very small V‐shift voltage.