Glycothermal synthesis and photoluminescence of YAG:Ce³⁺ nanophosphors

Y₃Al ₅O₁₂:Ce³⁺ (YAG:Ce ³⁺) nanophosphor powder was synthesized by glycothermal method, where a reaction between aluminum isopropoxide and acetates of yttrium and cerium(III) was induced in 1,4-butylene glycol in autoclave. According to X-ray diffraction profiles, YAG crystal structure was formed after glycothermal treatment at 300 °C for more than 1 h. The aggregation of the primary particles of ∼10 nm diameter was confirmed by TEM observation and dynamic light scattering. The intensity of photoluminescence (PL) due to 5d → 4f transition of Ce³⁺ increased with increasing the aging time at 300 °C during glycothermal treatment. The inductively coupled plasma atomic emission spectroscopy revealed that the atomic ratio of Ce/(Y + Ce) remained unchanged irrespective of the aging time at 300 °C. Therefore, this suggests that prolonged aging promotes the homogeneous incorporation of Ce ³⁺ into the interior of particle. Based on the characterization by thermal analysis and infrared absorption spectroscopy, the coordination of 1,4-butylene glycol and acetate on the surface of YAG:Ce³⁺ nanophosphors possibly plays a significant role in the PL enhancement.