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Title: One-step aerosol synthesis of a double perovskite oxide (KBaTeBiO 6 ) as potential catalysts for CO 2 photoreduction
This study presents a comprehensive investigation on the aerosol synthesis of a semiconducting double perovskite oxide with a nominal composition of KBaTeBiO 6 , which is considered as a potential candidate for CO 2 photoreduction. We demonstrate the rapid synthesis of the multispecies compounds KBaTeBiO 6 with extreme high purity and controllable size through a single-step furnace aerosol reactor (FuAR) process. The formation mechanism of the perovskite in the aerosol route is investigated using thermogravimetric analysis to identify the optimal reference temperature, residence time and other operational parameters in the FuAR synthesis process to obtain the highly pure KBaTeBiO 6 nanoparticles. It is observed that particle formation in the FuAR is based on a mixture of gas-to-particle and liquid-to-particle mechanisms. The phase purity of the perovskite nanoparticles depends on the ratio of the residence time and the reaction time. The particle size is strongly affected by the precursor concentration, residence time and the furnace temperature. Finally, the photocatalytic performance of the synthesized KBaTeBiO 6 nanoparticles is investigated for CO 2 photoreduction under UV-light. The best performing sample exhibits an average CO production rate of 180 μmol g −1 h −1 in the first half hour with a quantum efficiency of 1.19%, demonstrating KBaTeBiO 6 as a promising photocatalyst for CO 2 photoreduction.  more » « less
Award ID(s):
1806147
NSF-PAR ID:
10253134
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Nanoscale
ISSN:
2040-3364
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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