Woo Hyun-Joo, Hadrick Kay, Kim Taeho
Department of Biomedical Engineering, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan 48824, United States.
ACS Appl Opt Mater. 2024 Feb 27;2(3):445-452. doi: 10.1021/acsaom.3c00456. eCollection 2024 Mar 22.
This study presents an approach for synthesizing Eu/Eu-coactivated CaSiO nanophosphors, by adjusting the ratio of both activators within a singular host material. Utilizing a hydrothermal method complemented by a postreduction sintering process, we fabricated a series of phosphors characterized by uniform 30-50 nm spherical nanoparticles. These engineered phosphors manifest multichannel luminescence properties and exhibit simultaneous blue and red emission from Eu and Eu, respectively. Meticulous control of the 5% H-95% N reduction temperature allowed for precise tuning of the Eu and Eu ions within the host lattice, which enabled the strategic adjustment of their luminescent outputs. Utilizing X-ray photoelectron spectroscopy (XPS), we could discern subtle alterations in the europium oxidation state. By using a transmission electron microscope (TEM) and an X-ray diffractometer (XRD), we found that the subsequent changes by reductive sintering to particle size, morphology, and mixed crystal structures influenced the materials' luminescent characteristics. Our findings herald a significant advancement in solid-state lighting, with the potential for the use of Eu/Eu-coactivated calcium silicate nanophosphors to develop white light emission technologies endowed with enhanced color rendering and luminous efficacy.
本研究提出了一种通过调整单一基质材料中两种激活剂的比例来合成铕/铕共激活硅酸钙纳米磷光体的方法。利用水热法并辅以还原后烧结工艺，我们制备了一系列具有均匀30 - 50纳米球形纳米颗粒的磷光体。这些经过设计的磷光体表现出多通道发光特性，分别从铕和铕发出同时的蓝色和红色发射光。对5%氢气 - 95%氮气还原温度的精确控制使得能够在基质晶格内精确调节铕和铕离子，从而能够策略性地调整它们的发光输出。利用X射线光电子能谱（XPS），我们能够辨别铕氧化态的细微变化。通过使用透射电子显微镜（TEM）和X射线衍射仪（XRD），我们发现还原烧结对粒径、形态和混合晶体结构的后续变化影响了材料的发光特性。我们的研究结果预示着固态照明领域的重大进展，铕/铕共激活硅酸钙纳米磷光体有潜力用于开发具有增强显色性和发光效率的白光发射技术。
