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Chinese Optics Letters 2021年第3期19卷 13-16页

作者： Zongjie Zhang Wei Li Nan Ma Xiaoyong Huang College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan 030024China

Bright Eu3+-activated double-perovskite Sr2LaTaO6 red-emitting phosphors were successfully synthesized by a high-temperature solid-state method. Under near-ultraviolet excitation at 394 nm, optimal Sr2LaTaO6∶0.2 Eu3+phosphors emitted high-brightness red light around 613 nm with the International Commission on Illumination chromaticity coordinates(0.650,0.349). Notably, the color purity can reach 92%. Impressively, the favorable thermal stability of the Sr2LaTaO6∶0.2 Eu3+phosphors was characterized by temperature-dependent emission spectra at different temperatures from 303 to 463 K, and the emission intensity at 423 K remained 73% of its value at 303 K. All of the results suggested that the as-prepared Sr2LaTaO6∶0.2 Eu3+phosphors can be used in near-ultraviolet-excitable white light-emitting diodes as a red-emitting color converter.

关键词： Sr_(2)LaTaO_(6) Eu^(3+) double-perovskite phosphors

Different oxidation routes for lattice oxygen recovery of double-perovskite type oxides LaSrFeCoO6 as oxygen carriers for chemical looping steam methane reforming

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Journal of Energy Chemistry 2017年第3期26卷 501-509页

作者： Kun Zhao Yang Shen Zhen Huang Fang He Guoqiang Wei Anqing Zheng Haibin Li Zengli Zhao Key Laboratory of Renewable Energy Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640GuangdongChina Guangdong Key Laboratory of New and Renewable Energy Research and Development Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640GuangdongChina University of Chinese Academy of Sciences Beijing 100049China

double-perovskite type oxide LaSrFeCoO（LSFCO） was used as oxygen carrier for chemical looping steam methane reforming（CL-SMR） due to its unique structure and reactivity. Two different oxidation routes,steam-oxidation and steam-air-stepwise-oxidation, were applied to investigate the recovery behaviors of the lattice oxygen in the oxygen carrier. The characterizations of the oxide were determined by X-ray diffraction（XRD）, X-ray photoelectron spectroscopy（XPS）, hydrogen temperature-programmed reduction（H-TPR） and scanning electron microscopy（SEM）. The fresh sample LSFCO exhibits a monocrystalline perovskite structure with cubic symmetry and high crystallinity, except for a little impurity phase due to the antisite defect of Fe/Co disorder. The deconvolution distribution of XPS patterns indicated that Co,and Fe are predominantly in an oxidized state(Feand Fe) and(Coand Co), while O 1s exists at three species of lattice oxygen, chemisorbed oxygen and physical adsorbed oxygen. The double perovskite structure and chemical composition recover to the original state after the steam and air oxidation, while the Co ion cannot incorporate into the double perovskite structure and thus form the CoO just via individual steam oxidation. In comparison to the two different oxidation routes, the sample obtained by steam-oxidation exhibits even higher CHconversion, CO and Hselectivity and stronger hydrogen generation capacity.

关键词： double-perovskite Chemical looping Lattice oxygen Oxidizing agent Redox

Fabrication and photoluminescence characteristics of novel red-emitting Ba_(2)LuNbO_(6):Eu^(3+)double-perovskite phosphors on near UV WLEDs

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Journal of Rare Earths 2022年第8期40卷 1173-1180页

作者： Haihong Guo Ting Wang Bitao Liu Wei Gao Liang Xiu Zhenen Cui Hao Zhang Qianrui Ma Shaoqing Wang Ziyang Li Longchao Guo Guilong Yan Siufung Yu Xue Yu Xuhui Xu Jianbei Qiu College of Materials and Chemistry&Chemical Engineering Chengdu University of TechnologyChengdu 610059China The Department of Applied Physics The Hong Kong Polytechnic UniversityHong Kong 999077China Research Institute for New Materials Technology Chongqing University of Arts and SciencesChongqing 402160China College of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China School of Mechanical Engineering Chengdu UniversityChengdu 610059China

Red emitting phosphors play a significant role in accelerating the improvement of illumination quality for white light emitting diodes(WLEDs).In this work,by using solid-state reaction method,an efficient novel Ba_(2)LuNbO_(6):Eu^(3+)phosphor with double-perovskite structure was successfully ***,a series of Ba_(2)LuNbO_(6):Eu^(3+)red phosphors can be efficiently pumped by the near-ultraviolet(UV)light and then present high-brightness at orange emission(598 nm,~5D_(0)→~7 F_(1))and red emission(610 nm,~5D_(0)→~7 F_(2)).The ratio values of 610 to 598 nm in Ba_(2)LuNbO_(6):Eu^(3+)phosphors exceed 1 when the content of Eu^(3+)is larger than 0.4 mol,because the occupation of Eu^(3+)ions is changed from Lu^(3+)ions with symmetric sites to Ba^(2+)ions with asymmetric ***,the optimized concentration of Eu^(3+)at the~5D_(0)→~7 F_(2)transitions is obtained when x=1,indicating that there is non-concentration quenching in Ba_(2)LuNbO_(6):Eu^(3+)***,the CIE chromaticity coordinates of Ba_(2)LuNbO_(6):Eu^(3+)was calculated to be(0.587,0.361),the color purity was calculated to be 72.26%and internal quenching efficiency(IQE)was measured to be 67%.Finally,the thermal stability of Ba_(2)LuNbO_(6):Eu^(3+)phosphors was also *** work demonstrates that the novel double-perovskite red-emitting Ba_(2)LuNbO_(6):Eu^(3+)phosphors are prospective red emitting elements for WLEDs applications.

关键词： Ba_(2)LuNbO_(6):Eu^(3+) phosphors Non-concentration quenching double-perovskite Red emitting Rare earths

Emission-tunable Ba_(2)Y_(1-x)Sc_(x)NbO_(6):Bi^(3+)(0≤x≤1.0)phosphors for white LEDs

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Journal of Rare Earths 2022年第12期40卷 1819-1826,I0001页

作者： Zhihua Gao Fengyan Fu Lili Niu Min Jin Xiaohong Wang Department of Applied Chemistry Hengshui UniversityHengshui 053000China Sichuan University Chengdu 610041China

Here,we report a series of Bi^(3+)-doped Ba_(2)Y_(1-x)Sc_(x)NbO_(6)(0≤x≤1.0 mol)phosphors by using the traditional high temperature solid-state *** achieve the structural and photoluminescent(PL)information,several experimental characterizations and theoretical calculations were carried out,including X-ray diffraction(XRD),Rietveld refinement,UV-visible diffuse reflectance and PL spectra,temperature dependent PL spectra,and density functional theo retical(DFT)*** XRD results show that the Bi^(3+)-doped Ba_(2)Y_(1-x)Sc_(x)NbO_(6)samples belong to the double-perovskite phase with a cubic space group of Fm3 m,and the diffraction positions shift toward high diffraction angle when the larger Y^(3+)ions are gradually replaced by the smaller Sc^(3+)*** addition,the refined XRD findings show that the Bi^(3+)ions tend to substitute the Y^(3+)and Sc^(3+)sites in the Bi^(3+)-doped Ba_(2)Y_(1-x)Sc_(x)NbO_(6)0

关键词： Bi^(3+) double-perovskite Tunable emission Energy transfer White LEDs Rare earths

Efficient broadband near-infrared phosphor Sr_(2)ScSbO_(6):Cr^(3+) for solar-like lighting

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Science China Materials 2022年第3期65卷 748-756页

作者： Meng Zhao Shengqiang Liu Hao Cai Fangyi Zhao Zhen Song Quanlin Liu The Beijing Municipal Key Laboratory of New Energy Materials and Technologies School of Materials Sciences and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

For healthy lighting,daily lighting that considers both visible light and near-infrared(NIR)light is ***,at~900 nm,the extensively used solar-like phosphor-converted light-emitting diodes(pc-LEDs)are limited by a lack of high-performance NIR luminescent *** report a broadband NIR phosphor Sr_(2)ScSbO_(6):Cr^(3+) with a double perovskite-type structure,thus simultaneously demonstrating high luminescence efficiency and good thermal *** 550-nm excitation,Sr_(2)ScSbO_(6):Cr^(3+) demonstrates broadband NIR emission centered at~890 nm with luminescence internal/external efficiencies of 82.0%/35.7%,***,the luminescence integrated intensity at 430 K remains at~66.4% of the initial *** successfully fabricated pc-LED devices using a 465-nm-sized blue chip and other commercial phosphors,presenting a relatively complete solar-like spectrum from blue to NIR light and is expected to be used in solar-like lighting.

关键词： broadband near-infrared double-perovskite Sr_(2)ScSbO_(6):Cr^(3+) pc-LEDs solar-like spectrum

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层状类钙钛矿多铁性材料研究进展

硅酸盐学报 2017年第12期45卷 1707-1720页

作者：张大龙陈志伟黄伟川李晓光中国科学技术大学物理系合肥230026

多铁性材料的自旋、电荷、轨道、晶格等多重有序存在着复杂的相互作用,且对磁场、电场、光场、应变和温度等多种外界环境敏感,从而表现出一些新奇的物理现象,使其在存储器、传感器、微波等领域中有重要的应用价值。随着对单相多铁材料... 详细信息

多铁性材料的自旋、电荷、轨道、晶格等多重有序存在着复杂的相互作用,且对磁场、电场、光场、应变和温度等多种外界环境敏感,从而表现出一些新奇的物理现象,使其在存储器、传感器、微波等领域中有重要的应用价值。随着对单相多铁材料研究的深入,人们已从简单钙钛矿结构的多铁性研究转向复杂的层状类钙钛矿体系,其丰富而复杂的结构给人们提供了更广泛的设计和调控空间。介绍并分析了如double-perovskite(DP)、Ruddlesden-Popper(RP)、Aurivillius(AU)以及A_nB_nO_(3n+2)系列等层状类钙钛矿多铁性特征的研究进展。人们已发现Bi_2FeCrO_6等DP体系、(1–x)(Ca_ySr_(1–y))_(1.15)Tb_(1.85)Fe_2O_7–xCa_3Ti_2O_7等RP体系、Bi_4NdTi_3Fe_(1–x)Co_xO_(15_–Bi_3NdTi_2Fe_(1–x)Co_xO_(12–δ)等AU体系以及La_6(Ti_(0.67)Fe_(0.33))_6O_(20)层状材料等,均具有室温或近室温多铁性。最后提出了当前面临的问题和对未来的展望。

关键词：多铁性 double-perovskite Ruddlesden-Popper Aurivillius

Preparation and Photocatalytic Properties of LnBaCo<SUB>2</SUB>O<SUB>5+δ</SUB>(Ln = Eu, Gd, and Sm)

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Journal of Materials Science and Chemical Engineering 2015年第4期3卷 17-25页

作者： Bingqian Han Yuxiu Li Nan Chen Dongyang Deng Xinxin Xing Yude Wang Department of Materials Science and Engineering Yunnan University Kunming China Yunnan Province Key Lab of Micro-Nano Materials and Technology Yunnan University Kunming China

A new type of photocatalytic material, double-perovskite oxides, LnBaCo2O5+δ (Ln = Eu, Gd, and Sm) was synthesized via a conventional solid-state reaction process using Ln2O3, BaCO3 and Co2O3 as raw materials. X-ray diffraction results show that the crystalline structures are a pure orthorhombic lattice and are consistent with LnBaCo2O5+δ microparticles. The photocatalytic activity of the LnBaCo2O5+δ (Ln = Eu, Gd, and Sm) powders was further demonstrated in the degradation of Congo red (CR) under ultraviolet light irradiation with the dye solution concentration of 25 or 50 mg·L-1. The double-perovskite oxides LnBaCo2O5+δ show a certain photocatalytic activity during the degradation of CR under ultraviolet light, which means that they are one kind of the promising photocatalytic materials for the degradation of the azo dyes.

关键词： double-perovskite LnBaCo2O5+δ Photocatalysis Congo Red