Yim Chul Jin, Unithrattil Sanjith, Chung Woon Jin, Im Won Bin
School of Materials Science and Engineering, Chonnam National University, 300 Yongbong-Dong, Buk-gu, Gwangju, 500-757, Republic of Korea.
J Nanosci Nanotechnol. 2013 Dec;13(12):7850-4. doi: 10.1166/jnn.2013.8113.
Red emitting nanofibers, KGdTa2O7:Eu3+ were synthesized by electrospinning technique followed by heat treatment. As-prepared uniform fiber precursor with diameter ranging from about 700 nm to about 900 nm were calcined after removing organic species by calcination. The fiber surface become rough and diameter decreased to about 250-340 nm range due to decomposition of organic species and formation of inorganic phase. Morphology, structural and photoluminescent properties of fibers were analyzed using thermogravimetric and differential thermal analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL). TG-DTA analysis indicates that KGdTa2O7:Eu3+ began to crystalize at 520 degrees C. Fibers annealed at 900 degrees C formed well crystallized uniform fibers. Under ultraviolet excitation KGdTa2O7:Eu3+ exhibits red emission due to transitions in 4f states of Eu3+. The excitation band is dominated by the Eu(3+)--O2-charge transfer band peaked at 289 nm. The emission peak is in the region that is ideal for red light emission.
通过静电纺丝技术并随后进行热处理合成了发红光的纳米纤维KGdTa2O7:Eu3+。将制备好的直径约为700纳米至约900纳米的均匀纤维前驱体在通过煅烧去除有机物质后进行煅烧。由于有机物质的分解和无机相的形成，纤维表面变得粗糙，直径减小到约250 - 340纳米范围。使用热重和差示热分析（TG - DTA）、X射线衍射（XRD）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、高分辨率透射电子显微镜（HRTEM）和光致发光（PL）对纤维的形态、结构和光致发光性能进行了分析。TG - DTA分析表明KGdTa2O7:Eu3+在520℃开始结晶。在900℃退火的纤维形成了结晶良好的均匀纤维。在紫外激发下，KGdTa2O7:Eu3+由于Eu3+的4f态跃迁而呈现红色发射。激发带以在289纳米处达到峰值的Eu(3+) - O2 - 电荷转移带为主。发射峰位于适合红光发射的区域。
