Tuning Mixed-Valent Eu(2+) /Eu(3+) in Strontium Formate Frameworks for Multichannel Photoluminescence.
Cooperative performance of mixed-valent Eu(2+) /Eu(3+) in single-compound phosphors offers significant advantages in color rendering and luminescence efficiency, but their synthesis is challenging because of Eu(2+) oxidation. Using the tunable nature of the metal-ion nodes in metal-organic frameworks (MOFs), we present an in situ reduction and crystallization route for preparing MOFs and doping Eu(2+) /Eu(3+) with a controlled ratio. These materials exhibit rich photoluminescence, including intrinsic- and sensitized-emissions of Eu(2+) and Eu(3+) , and long-lived luminescence from charge transfer. Color rendering can be easily achieved by fine-tuning the valence states of Eu. A linear relation between temperature and the intensity ratio of Eu(2+) /Eu(3+) emissions provides outstanding properties for applications as self-calibrated luminescent thermometers with a wide working temperature range. Further incorporation of Tb(3+) into the MOFs results in white light, utilizing all Eu(2+) ,Tb(3+) , and Eu(3+) emissions in a single crystalline lattice.
School for Radiological and interdisciplinary Sciences (RAD-X), Soochow University, 199 Renai Road, Suzhou, 215123, China.
Wei
W
Liu
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University-Western University Center for Synchrotron Radiation Research, Soochow University, 199 Ren'ai Road, Suzhou, 215123, China.
Lijia
L
Liu
School for Radiological and interdisciplinary Sciences (RAD-X), Soochow University, 199 Renai Road, Suzhou, 215123, China.
Yanlong
Y
Wang
School for Radiological and interdisciplinary Sciences (RAD-X), Soochow University, 199 Renai Road, Suzhou, 215123, China.
Lanhua
L
Chen
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University-Western University Center for Synchrotron Radiation Research, Soochow University, 199 Ren'ai Road, Suzhou, 215123, China.
John A
JA
McLeod
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University-Western University Center for Synchrotron Radiation Research, Soochow University, 199 Ren'ai Road, Suzhou, 215123, China.
Linju
L
Yang
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University-Western University Center for Synchrotron Radiation Research, Soochow University, 199 Ren'ai Road, Suzhou, 215123, China.
Jia
J
Zhao
School for Radiological and interdisciplinary Sciences (RAD-X), Soochow University, 199 Renai Road, Suzhou, 215123, China.
Zhiyong
Z
Liu
School for Radiological and interdisciplinary Sciences (RAD-X), Soochow University, 199 Renai Road, Suzhou, 215123, China.
Juan
J
Diwu
School for Radiological and interdisciplinary Sciences (RAD-X), Soochow University, 199 Renai Road, Suzhou, 215123, China.
Zhifang
Z
Chai
Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida, 32306, USA.
Thomas E
TE
Albrecht-Schmitt
Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois, 60439, USA. gkliu@anl.gov.
Guokui
G
Liu
School for Radiological and interdisciplinary Sciences (RAD-X), Soochow University, 199 Renai Road, Suzhou, 215123, China. shuaowang@suda.edu.cn.
Shuao
S
Wang
europium; luminescence; metal-organic frameworks; mixed valence; photoluminescence