A novel light-emitting device is provided. The light-emitting device includes a first electrode, a second electrode, and a light-emitting layer between the first electrode and the second electrode. The light-emitting layer includes an organometallic complex emitting phosphorescence at room temperature and a light-emitting material emitting fluorescence. The organometallic complex includes a ligand with at least one first substituent selected from a branched alkyl group having 3 to 12 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms in a ring, and a trialkylsilyl group having 3 to 12 carbon atoms. An absorption spectrum of the light-emitting material has the longest-wavelength edge at a first wavelength λabs (nm), and a phosphorescence spectrum of the organometallic complex has the shortest-wavelength edge at a second wavelength λp (nm). The first wavelength λabs (nm) is longer than the second wavelength λp (nm).
提供了一种新型的发光装置。该发光装置包括第一电极、第二电极和位于第一电极和第二电极之间的发光层。发光层包括一种有机
金属络合物,在室温下发出
磷光,并且一种发出荧光的
发光材料。有机
金属络合物包括一个
配体,其至少包含一种第一取代基,所述第一取代基选择自分支烷基,其具有3至12个碳原子,取代或未取代的环烷基,其在环中具有3至10个碳原子或三烷基
硅基,其具有3至12个碳原子。
发光材料的吸收光谱在第一波长λabs(nm)处具有最长波长边缘,并且有机
金属络合物的
磷光谱在第二波长λp(nm)处具有最短波长边缘。第一波长λabs(nm)比第二波长λp(nm)长。