Morphology-controlled synthesis of red-emitting CdTe@SrSO4 composites phosphors for white LEDs

Red-emitting CdTe@SrSO 4 composites phosphors have been successfully fabricated via a two-step precipitation and following electrostatic assembly process. By adjusting the molar ratio of [Sr 2+ ]/[SO 4 2− ], the morphologies of SrSO 4 products vary from rods to rhombs with the increasing thickness, and comparative luminescence properties and phase formation mechanism of as-prepared CdTe@SrSO 4 composites have been investigated. The CdTe@SrSO 4 composites with a rod-like shape show optimum luminescence properties, as well as relatively good thermal stability. White LED prototype based on the CdTe@SrSO 4 composites has been fabricated, and a CIE coordinate of (0.400, 0.389), the correlated color temperature (CCT) of 3600 K, and color rendering index (CRI) of 94.3 can be achieved. The results indicate that CdTe@SrSO 4 composites may have potential in phosphor-converted white LEDs.