Bubble Dynamics and Directional Marangoni Flow Induced by Laser Heating of Silicon Nanodisk Arrays
Artikel i vetenskaplig tidskrift, 2025

Gold nanostructures have been extensively used asphotothermal heat sources in a variety of studies due to theirchemical inertness, biocompatibility, and advantageous thermo-plasmonic properties. However, gold nanostructures are prone tosurface melting and thermal deformation, which, in some cases,limit their applicability. In this study, we investigate micrometer-sized amorphous silicon nanodisk arrays as a stable andbiocompatible alternative for the particular application of photo-thermally induced microbubble formation and generation of strongdirectional Marangoni flows in water. By using time-modulatedcontinuous-wave laser heating, we show that the induced flows canmove microparticles tens of micrometers across a substrate surface.The direction of particle movement can be preselected by utilizingasymmetric pairs of nanodisk arrays as heat sources or dynamically controlled by altering the laser spot position relative to asymmetric pair of arrays. We also demonstrate that average bubble size and particle displacement positively correlate and cruciallydepend on the laser modulation frequency. These results are discussed in terms of the temporal dynamics of bubble growth followingnucleation. Our findings highlight the potential of using silicon nanostructures as substrates for generating strong thermocapillaryflows on the micrometer scale, with potential applications in chemical mixing, pumping, particle sorting, and mass transport.

vapor bubble

optofluidics

thermocapillary

optothermal heating

marangoni

microboiling

Författare

Pantea Dara

Chalmers, Fysik, Nano- och biofysik

Mikael Käll

Chalmers, Fysik, Nano- och biofysik

Journal of Physical Chemistry C

1932-7447 (ISSN) 1932-7455 (eISSN)

Vol. 129 11 5502-5510

Optotermisk Marangonikonvektion och sensorik på nanoskala

Vetenskapsrådet (VR) (2020-04063), 2020-12-01 -- 2024-11-30.

Styrkeområden

Nanovetenskap och nanoteknik

Energi

Materialvetenskap

Ämneskategorier (SSIF 2025)

Nanoteknik

Strömningsmekanik

Annan fysik

Infrastruktur

Myfab (inkl. Nanotekniklaboratoriet)

DOI

10.1021/acs.jpcc.4c08101

Mer information

Senast uppdaterat

2025-04-04