Gd_2Hf_2O_7∶Ce纳米粒子表观活化能对发光性能影响  

Effect of Apparent Activation Energy on Luminescence Properties of Gd_2Hf_2O_7∶ Ce Nanoparticles

作　　者：李军[1] 马伟民[1] 葛利芳 魏明炜 张艳丽[1] 聂力[1] 

机构地区：[1]沈阳化工大学材料科学与工程学院沈阳市先进陶瓷制备技术及应用重点实验室,沈阳110142

出　　处：《人工晶体学报》2016年第1期119-127,共9页Journal of Synthetic Crystals

基　　金：国家自然科学基金(51274143);沈阳市先进陶瓷制备技术及应用重点实验室建设项目(F12-259-1-00)

摘　　要：采用正、反向共沉淀法制备了掺杂Ce的Gd_2Hf_2O_7纳米粒子,用XRD、SEM、TG-DTA和荧光分度计等测试手段分析了物相形貌及发光性能;在不同升温速率条件下由热力学计算了样品的表观活化能。结果表明:两种滴定法得到的前躯体分别经煅烧物相变化同为3个阶段,由Doyel-Ozawa法和Kissinger法计算取两者的平均值得到各阶段的表观活化能分别是48.18 kJ·mol^(-1)、80.35 kJ·mol^(-1)、285.7 kJ·mol^(-1)和39.18 kJ·mol^(-1)、64.3 kJ·mol^(-1)、277.82 kJ·mol^(-1),晶粒生长活化能是29.61 kJ·mol^(-1)和22.61 kJ·mol^(-1)。后者样品分别在567 nm波长下的激发光谱和450 nm波长处发射光谱的相对发光强度优于前者,可见纳米粒子的活化能越小对发光离子的能级跃迁起到促进作用。Ce doped-Gd_2Hf_2O_7 nano-powders were synthesized by the NSC and RSC co-precipitation methods.The phase composition,morphology and luminescent properties of the samples were characterized by XRD,SEM,TG-DTA and fluorescence photometer.Powders' thermal analysis kinetics and activation energy in the synthesis process were also calculated under different heating rates.The results show that the precursors prepared by NSC and RSC co-precippitation methods decompose of calcinations in three stages.The average apparent activation energies of the three stages of precursors prepared by NSC and RSC,calculated through the Doyel-Ozawa and Kissinger methods,are 48.18 kJ ?mol^(-1),80.35 kJ ? mol^(-1),285.7 kJ ? mol^(-1) and 39.18 kJ ? mol^(-1),64.3 kJ ? mol^(-1),277.82 kJ ?mol^(-1) respectively.The activation energies of grain growth under different co-precipitation methods are29.61 kJ · mol^(-1) and 22.61 kJ · mol^(-1) severally.It is showed that RSC co-precippitation method has excellent luminescence properties with higher intensity of excitation spectrum excited by 567 nm and emission spectrum excited by 450 nm.The reason is that the smaller the activation energy of the nanoparticle,the more it can promote the energy level transition of the glowing ion.

关 键 词：Gd2Hf2O7∶Ce纳米粒子 正、反向共沉淀法 活化能 发光性能 

分 类 号：TB383.1[一般工业技术—材料科学与工程]