本研究之主旨在開發快速合成Ce : YAG粉末的經濟製程，使用硝酸釔、硝酸鋁及硝酸鈰作為起始原料，溶解於醇類溶劑中形成澄清透明溶液，不經滴定、沈澱等其他步驟，直接放入壓力釜中進行溶熱反應。本研究探討使用溶劑種類對於反應速率與產物粒徑、結晶性之間的關連性。研究結果發現，以溶熱法合成YAG粉末的反應速率，與使用醇類溶劑的超臨界溫度以及介電常數有著緊密的關連性。由於溶劑的介電常數在超臨界溫度之上時會急劇下降，使得硝酸鹽濃度瞬間因過飽和而誘發均勻成核成長作用，形成粒徑均一之球形Ce : YAG粉末。由於各種醇類溶劑的介電常數及超臨界溫度各不同，因此整體溶熱反應效率、產物結晶性及粒徑大小均強烈受到溶劑種類的影響。本研究分別選用了五種不同醇類溶劑，透過反應溫度與時間的控制，確認溶劑的超臨界溫度為決定反應速率的主要因素，而產物之結晶性則由溶劑的介電常數主導。以本研究所開發的快速溶熱製程，可在285ºC下反應5小時，即獲得次微米尺度之單一粒徑Ce : YAG單晶粒子，可應用做為白光LED之螢光粉。

One-pot synthesis process method to prepare cerium doped Y3Al5O12 (Ce:YAG) was via solvothermal method was reported in this work. Staring solution was prepared by using yttrium nitrate, aluminum nitrate and cerium nitrate dissolved in different alcohols solvents and then placed directly into stainless autoclave for the solvothermal reaction. Via a mild working temperature (< 285°C) and efficient reaction time (5h), single-phased, spherical shape and mono-size distributed grain size of Ce:YAG particles were obtained. The effects of the solvent properties, including supercritical point and dielectric constant, on the resulting Ce:YAG products were carefully investigated. The Ce:YAG powders showed a broad emission band in the green-yellow range having maximum intensity at 530 nm under excitation wavelength at 460 nm. This solvothermal synthesis method provides a new and efficient approach for the preparation of YAG powders.

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