二氧化鈰基螢光粉之晶格效應與感溫分析

Abstract

傳統接觸式溫度計在操作過程中會影響物質的實際溫度，特別是對微米及奈米尺度系統的測溫結果有嚴重干擾。相比之下，非接觸式光學溫度計具有非接觸操作、寬工作溫度範圍、快速響應和高空間解析度的優點。滿足快速準確測量的要求是工業界迫切的目標。本研究設計一種非接觸式螢光粉感溫計，並針對晶格結構、光學性質、熱穩定性做出系統性的探討。透過EDTA螯合輔助的水熱途徑開發一種Zn2+, Tb3+共活化氧化鈰基螢光粉。材料的XRD、TEM、XPS、光致發光放射光譜、溫度敏感性、變溫解析度及其他特性分析將被詳細討論。Zn2+的摻雜影響螢光粉結構之晶格尺寸，對材料本身之形貌與尺寸影響不明顯。共摻雜活化劑濃度很大程度改變主體材料中的發光中心對稱性及衍生的晶格效應。發現在摻雜鋅離子濃度為10 mol% 時螢光粉於波長543 nm附近的光致發光放射峰強度增加至摻雜前的七倍。趨於明顯的主體材料放射帶使發光顏色由綠色轉為青色。Zn2+及Tb3+對Ce4+的取代可藉由元素特徵峰、Ce3+/Ce4+積分比例以及氧空位的提升來直接證實。隨著溫度上升，螢光粉材料的非輻射弛豫現象會越發明顯。主體晶格對Tb3+活化劑之螢光強度比變化表明螢光粉在溫度323 K至498 K間具有優秀的耐熱性與可重複性。材料在該溫度區間內表現出波茲曼行為，並顯示出良好的絕對溫度敏感性與解析度。種種結果正實了所開發之螢光粉材料作為測溫用螢光粉溫度計的應用潛力。

Traditional contact thermometry have an impact on the actual temperature of the substance during operation. Contrarily, the benefits of non-contact optical thermometry include quick response times, contact-free operation, and excellent spatial resolution. The immediate goal of industry is to meet the demands for fast and accurate measurements. This study involved the development of a non-contact phosphor thermometry and a thorough analysis of the lattice structure, optical characteristics, and thermal stability. Ceria-based phosphors co-activated with Zn2+ and Tb3+ were prepared through a hydrothermal route with EDTA chelation. The detailed investigation of the material using XRD, TEM, XPS, and photoluminescence emission spectroscopy would be covered. The lattice size and distortion of the phosphor structure were discovered to be impacted by the doping content of Zn2+ ions. The concentration of co-doping activators significantly modulated lattice effects and luminescence center symmetry of the host material. As the concentration of zinc ions reached 10 mol%, the photoluminescent emission intensity of prepared phosphors increased to seven times. The substitution of Zn2+ and Tb3+ for Ce4+ could be directly confirmed by the elemental characteristic peaks, the Ce3+/Ce4+ integral ratio, and the fluctuation of oxygen vacancies. The non-radiative relaxation phenomenon became visible with rising temperature. According to the luminescent intensity ratio of the host lattice to Tb3+ ions, the co-activated phosphors exhibited decent sensitivity and resolution in the temperature range of 323-498 K. The high reproducibility and thermal stability of the phosphors were also proven. The results supported the application value of the developed material as phosphor thermometry.