Improvement of electron injection of organic light-emitting devices by inserting a thin aluminum layer into cesium carbonate injection layer*
Xin Li-Wena),b),c), Wu Xiao-Minga),b),c)†, Hua Yu-Lina),b),c)‡, Xiao Zhi-Huia),b),c), Wang Lia),b),c), Zhang Xina),b),c), Yin Shou-Gena),b),c)
       
(a) Current density–voltage–luminance characteristics; (b) current efficiency–current density characteristics of the devices based on DNCA with and without a thin Al layer.