Structural Modulation Induced Intensity Enhancement of Full Color Spectra: A Case of Ba3ZnTa2-xNbxO9: Eu3+ Phosphors
Structural Modulation Induced Intensity Enhancement of Full Color Spectra: A Case of Ba3ZnTa2-xNbxO9: Eu3+ Phosphors
复制标题
结构调制诱导全彩光谱强度增强：以 Ba3ZnTa2-xNbxO9: Eu3 荧光粉为例
DOI：
10.1039/d0tc01201g
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发表时间：
2020
影响因子：
6.4
通讯作者：
Mingmei Wu
中科院分区：
文献类型：
--
作者：
Xiaohui Li;Lei Zhou;Junyu Hong;Shiman He;Xiping Jing;Miroslav D.Dramićanin;Jianxin Shi;Mingmei Wu
Modulation of structural order-disorder transition and structural oxygen defects can provide fundamental and key insights for the optimization of the luminescence performance of phosphors. In this study, the luminescence of Ba3ZnTa2O9 (BZT) was systematically elucidated, including the emission arising from the charge transfer (Nb5+/Ta5+→O2-) and anti-site oxygen defect emission due to the B-site disordering (defect type: [2ZnNb3- + 3Vo2+]), as corroborated by the electronic structural calculations and detailed experiments. We present the two-step design for the optimization of luminescence properties of Ba3ZnTa2O9 phosphor. In the first step, the B-site equivalent doping (Ta5+ substituted by Nb5+) was used to modulate the B-site atomic arrangement, which induced the formation of the cubic phase with B-site full disordering. In the second step, the A-site nonequivalent doping (Ba2+ substituted by Eu3+) was used to decrease the oxygen defect concentration. After two-step optimization, the photoluminescence excitation spectrum of the Ba3-yEuyZnNb2O9 (y = 0.1) shows a broad band excitation (300-400 nm) which well matches the near-UV LED chip emission. Even more importantly, the emission spectrum covers the entire visible spectral region and exhibits a remarkably enhanced emission intensity (40 times enhancement when compared to the intrinsic BZT). The fabricated LED device comprised from an n-UV chip ( = 370 nm) and a single-component Ba3-yEuyZnNb2O9 (y = 0.1) phosphor coating emits a warm white light with low correlated color temperature (CCT = 4813 K) and good color rendering index (Ra = 82.36).
