Luminescence Properties of Cs<sub>3</sub>Cu<sub>2</sub>I<sub>5</sub> Phosphors Powder with Solid State Method

The low-temperature solid-state method is utilized to prepare Cs 3 Cu 2 I 5 phosphors powder by using the cesium iodide (CsI) and cuprous iodide (CuI) as the raw materials. The phase structures of samples were investigated by using X-ray spectrum and steady-state fluorescence spectrometer. The experimental results show that all of samples were crystallized in the orthorhombic structure with pnma space group at the annealing temperature of 100-400°C. Cs 3 Cu 2 I 5 phosphors exhibits a strong blue photoluminescence emission with peak at 440nm under excitation at 310nm. With the increase of the annealing temperature in the range of 100-400°C, the photoluminescence quantum yield (PLQY) of Cs 3 Cu 2 I 5 powder achieved the 79.95%. It is revealed that the prepared Cs 3 Cu 2 I 5 powder phosphors potentially have the promising application in the blue light emitting materials.