Microwave-Induced Interfacial Nanobubbles

Tools

Wang, L., Miao, X. and Pan, G. ORCID: 0000-0003-0920-3018, 2016. Microwave-Induced Interfacial Nanobubbles. Langmuir, 32 (43), pp. 11147-11154. ISSN 0743-7463

Preview

Text
PubSub5499_Pan.pdf - Post-print
Download (1MB) | Preview

Official URL: http://doi.org/10.1021/acs.langmuir.6b01620

Abstract

A new method for generating nanobubbles via microwave irradiation was verified and quantified. AFM measurement showed that nanobubbles with diameters ranging in 200 - 600 nm were generated at water-HOPG surface by applying microwave to aqueous solutions with 9.0 - 30.0 mg/L of dissolved oxygen. Graphite displays strong microwave absorption and transmits high thermal energy to surface. Due to high dielectric constant (20 °C, 80 F/m) and dielectric loss factor, water molecule has strong absorption ability for microwave. The thermal and non-thermal effects of microwave both had contributions to decrease gas solubility and that facilitated nanobubble nucleation. The yield of nanobubbles increased about ten times when irradiation time increased from 60 s to 120 s at 200 W microwave. The nanobubbles density increased from 0.8 to 15 numbers/μm2 by improving working power from 200 to 600 W. An apparent improvement of nanobubbles yield was obtained between 300 and 400 W, and the resulting temperature was 34 - 52 °C. When the initial dissolved oxygen increased from 11.3 to 30.0 mg/L, the density of nanobubbles increased from 1.2 to 13 numbers/μm2. The generation of nanobubbles could be well controlled by adjusting gas concentration, microwave power or irradiation time. The method maybe valuable in preparing surface nanobubbles quickly and conveniently for various applications, such as catalysis, hypoxia/anoxia remediation or as templates to prepare nanoscale materials.

Item Type:

Journal article

Publication Title:

Langmuir

Creators:

Wang, L., Miao, X. and Pan, G.

Publisher:

American Chemical Society

Date:

28 May 2016

Volume:

Number: