Floating synthesis with enhanced catalytic performance via acoustic levitation processing |
| |
Affiliation: | 1. MOE Key Laboratory of Materials Physics and Chemistry Under Extraordinary Conditions, School of Physical Science and Technology, Northwestern Polytechnical University, Xi''an 710072, China;2. School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi''an 710072, China;3. Key Laboratory for Liquid-Solid Structural of Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061, China |
| |
Abstract: | Acoustic levitation supplies a containerless state to eliminate natural convection and heterogeneous crystal nucleation and thus provides a highly uniform and ultra clean condition in the confined levitating area. Herein, we attempt to make full use of these advantages to fabricate well dispersed metal nanoparticles. The gold nanoparticles, synthesized in an acoustically levitated droplet, exhibited a smaller size and improved catalytic performance in 4-nitrophenol reduction were synthesized in an acoustically levitated droplet. The sound field was simulated to understand the impact of acoustic levitation on gold nanoparticle growth with the aid of crystal growth theory. Chemical reducing reactions in the acoustic levitated space trend to occur in a better dispersed state because the sound field supplies continuous vibration energy. The bubble movement and the cavitation effect accelerate the nucleation, decrease the size, and the internal flow inside levitated droplet probably inhibit the particle fusion in the growth stage. These factors lead to a reduction in particle size compared with the normal wet chemical synthetic condition. The resultant higher surface area and more numerous active catalytic sites contribute to the improvement of the catalytic performance. |
| |
Keywords: | Acoustic levitation Containerless state Gold nanoparticles Catalysis Finite element analysis |
本文献已被 ScienceDirect 等数据库收录! |
|