TY - JOUR
T1 - In situ temperature measurements of reaction spaces under microwave irradiation using photoluminescent probes
AU - Ano, Taishi
AU - Kishimoto, Fuminao
AU - Sasaki, Ryo
AU - Tsubaki, Shuntaro
AU - Maitani, Masato M.
AU - Suzuki, Eiichi
AU - Wada, Yuji
N1 - Funding Information:
This study was supported in part by a Grant-in-Aid for Scientific Research (A) 25249113, a Grant-in-Aid for Exploratory Research, Japan, the ASPIRE League Research Grant 2014 and 2015, Tokyo Tech, Research Grant of TEPCO Memorial Foundation, and the Demonstration and Standardization Project Using New Electric Devices, NEDO.
Publisher Copyright:
© the Owner Societies.
PY - 2016
Y1 - 2016
N2 - We demonstrate two novel methods for the measurement of the temperatures of reaction spaces locally heated by microwaves, which have been applied here to two example systems, i.e., BaTiO3 particles covered with a SiO2 shell (BaTiO3-SiO2) and layered tungstate particles. Photoluminescent (PL) probes showing the temperature-sensitivity in their PL lifetimes are located in the nanospaces of the above systems. In the case of BaTiO3-SiO2 core-shell particles, rhodamine B is loaded into the mesopores of the SiO2 shell covering the BaTiO3 core, which generates the heat through the dielectric loss of microwaves. The inner nanospace temperature of the SiO2 shell is determined to be 28 °C higher than the bulk temperature under microwave irradiation at 24 W. On the other hand, Eu3+ is immobilized in the interlayer space of layered tungstate as the PL probe, showing that the nanospace temperature of the interlayer is only 4 °C higher than the bulk temperature. This method for temperature-measurement is powerful for controlling microwave heating and elucidates the ambiguous mechanisms of microwave special effects often observed in chemical reactions, contributing greatly to the practical application of microwaves in chemistry and materials sciences.
AB - We demonstrate two novel methods for the measurement of the temperatures of reaction spaces locally heated by microwaves, which have been applied here to two example systems, i.e., BaTiO3 particles covered with a SiO2 shell (BaTiO3-SiO2) and layered tungstate particles. Photoluminescent (PL) probes showing the temperature-sensitivity in their PL lifetimes are located in the nanospaces of the above systems. In the case of BaTiO3-SiO2 core-shell particles, rhodamine B is loaded into the mesopores of the SiO2 shell covering the BaTiO3 core, which generates the heat through the dielectric loss of microwaves. The inner nanospace temperature of the SiO2 shell is determined to be 28 °C higher than the bulk temperature under microwave irradiation at 24 W. On the other hand, Eu3+ is immobilized in the interlayer space of layered tungstate as the PL probe, showing that the nanospace temperature of the interlayer is only 4 °C higher than the bulk temperature. This method for temperature-measurement is powerful for controlling microwave heating and elucidates the ambiguous mechanisms of microwave special effects often observed in chemical reactions, contributing greatly to the practical application of microwaves in chemistry and materials sciences.
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U2 - 10.1039/c6cp02034h
DO - 10.1039/c6cp02034h
M3 - Article
AN - SCOPUS:84971245115
SN - 1463-9076
VL - 18
SP - 13173
EP - 13179
JO - Physical Chemistry Chemical Physics
JF - Physical Chemistry Chemical Physics
IS - 19
ER -