ZnGa2O4：Mn2+螢光體中Al3+離子置換對其發光特性影響

The influence of luminescence by replacing Al3+ in ZnGa2O4:Mn2+ phosphor

洪宏偉(Hung-Wei Hung)

指導教授 ： 徐開鴻

國立臺北科技大學/工程學院/材料科學與工程研究所/碩士(2008年)

https://doi.org/10.6841/NTUT.2008.00035

摘要

本實驗是以固態反應法合成摻雜Mn2+為激活劑的ZnGa2O4與ZnAl2O4螢光體，研究重點在於母體中改變氧化鎵(Ga2O3)與氧化鋁(Al2O3)之比例，在還原氣氛下燒成ZnGa2-2xAl2xO4:Mn2+螢光體。以X光繞射儀(XRD)鑑定結晶相；以螢光光譜儀(PL)檢測螢光體之光激發光特性；以掃描式電子顯微鏡(SEM)觀察表面形貌，探討改變Ga/Al置換比對於晶體結構與發光特性之影響。由實驗結果顯示在燒成溫度1200℃下持溫1小時，可合成ZnGa2-2xAl2xO4:Mn2+之螢光體。當x＜0.5時晶格產生變形導致XRD的特徵峰值往大角度偏移且強度下降的傾向。而由螢光光譜分析得知ZnGa2-2xAl2xO4:Mn2+之激發與放射波峰隨著x值的增加而強度漸減。以505nm波長偵測產生6A1(6S)→4T2(4G) 448nm；6A1(6S)→4A1, 4E 427nm；6A1(6S)→4T2(4D) 382nm以及在x＜0.25時，波長328nm位置產生Mn2+的電荷轉移吸收和波長359nm位置產生6A1(6S)→4E(4D)等能階躍遷的激發光譜，而當x＞0.25時，波長328nm位置的吸收峰便消失。所合成的螢光體受此特性吸收峰激發，得到4T1(4G)→6A1(6S) 505nm青綠光寬幅的放射光譜。相較各螢光體的光譜分析，發現利用此方法配置所得到的發光強度分別為ZnGa2O4最強，ZnGa2-xAl2xO4次之，而ZnAl2O4最弱。

關鍵字

螢光粉 ； 固態反應法 ； ZnGa2O4:Mn2+ ； ZnAl2O4:Mn2+

並列摘要

This experiment used the solid state reaction method to synthesize the ZnGa2O4 and ZnAl2O4 phosphors that doped with Mn2+ activator. The key is changing the Ga2O3 and Al2O3 ratios in the host lattice, synthesize ZnGa2-2xAl2xO4:Mn2+ phosphors by firing temperature in reduction atmosphere. Use the X-ray Diffractometer (XRD) to analyzed the lattice crystal structure, the fluorescence spectrometer to analyzed the phosphorescence characteristics, and the scanning electron microscope (SEM) to observed the surface structure, to probe into the influence of luminescence and lattice structure by changing Ga/Al ratios. The result reveals that can synthesize ZnGa2-2xAl2xO4:Mn2+ phosphor at firing 1200℃ and soaking for one hour. When the x＜0.5 causing the lattice deform and lead to XRD characteristic peak deviating from large angle and the highest peak have been trending down of the intensity. Besides, by the fluorescence spectrometer analyzing, the excitation and emission spectra of ZnGa2-2xAl2xO4:Mn2+ comply with x values increase and decrease of intensity. The detected wavelength by 505nm produces energy levels of 6A1(6S)→4T2(4G) 448nm；6A1(6S)→4A1, 4E 427nm；6A1(6S)→4T2(4D) 382nm and when the x＜0.25, the wavelength of 328nm brings charge-transfer absorption of Mn2+ and the 359nm brings 6A1(6S)→4E(4D) energy level transition. when the x＞0.25, the absorption of 328nm wavelength position no longer appear. phosphor can be excited through these characteristic absorption peak, and showed a broad band green emission which due to the 4T1(4G)→6A1(6S) 505nm transition. Compared with each phosphors spectra, find that utilizing this method prepared received the strongest of luminous intensity is ZnGa2O4, the ZnGa2-xAl2xO4 takes second and ZnAl2O4 is the lowest.

並列關鍵字

phosphor ； solid-state reaction method ； ZnGa2O4:Mn2+ ； ZnAl2O4:Mn2+

參考文獻

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