Dy:YAG phosphor coating using the solution precursor plasma spray process

Dy:YAG phosphor coatings were deposited using the solution precursor plasma spray process. The phase composition, microstructure, and photoluminescent properties of the as-deposited coatings were investigated. X-ray diffraction analysis confirmed that the coating is mainly composed of the YAG phase with a small amount of an intermediate YAP phase. Scanning electron microscopy micrograph revealed that the as-sprayed coating has columnar structures with a thickness of ∼60 μm. The measurement of photoluminescent properties indicated that the phosphor coating exhibits two predominant emission regions: a blue region (470-500 nm) and a yellow region (560-600 nm), which are assigned to ⁴F_9/2-⁶H_15/2 and ⁴F_9/2-⁶H_13/2 transitions, respectively.