Morphology control and luminescence properties of red-emitting BaSiF 6 :Eu 3+ hexagonal nanorod phosphors for WLEDs

To promote the development of solid-state lighting industry, exploring excellent inorganic phosphors has been always a scientific and applied hot issue. Herein, a series of efficient red BaSiF 6 :Eu 3+ hexagonal nanorod phosphors with varied size and morphology were successfully prepared through a hydrothermal route. The reaction time, dosage of surfactant and solvent play an important role in the formation of the nanorod structures. The corresponding formation mechanism was discussed and revealed. The effects of surfactant, reaction time and solvent on photoluminescence properties of the as-prepared BaSiF 6 :Eu 3+ nanorod phosphors were investigated in detail. Under excitation at 394 nm, all samples emit bright red light due to the typical Eu 3+ 4f-4f transitions. Comparing the luminescence intensity of samples with different size of nanorods, it is found that the length of the nanorod is about 10–20 μm, the luminescence intensity of the sample is 3–5 times of the initial intensity of the nanorod sample that the length is around 30–40 μm. Moreover, when adding ethylene glycol as a solvent, the luminescence intensity of samples with different morphology increases with the increase of the reaction time. Importantly, as the temperature rising to 150 °C, the integrated intensity of the as-prepared sample still could obtain more than 95% of the intensity at room temperature, indicating the phosphors show excellent thermal stability. Thus, the as-prepared BaSiF 6 :Eu 3+ nanorod phosphor is a potential red-emitting phosphor for white light-emitting diodes (WLEDs).