Daniele Vella (Author), Aleš Mrzel (Author), Aljaž Drnovšek (Author), Vasyl Shvalya (Author), Matija Jezeršek (Author)

Abstract

Photoacoustic devices generating high-amplitude and high-frequency ultrasounds are attractive candidates for medical therapies and on-chip bio-applications. Here, we report the photoacoustic response of graphene nanoflakes – Polydimethylsiloxane composite. A protocol was developed to obtain well-dispersed graphene into the polymer, without the need for surface functionalization, at different weight percentages successively spin-coated onto a Polydimethylsiloxane substrate. We found that the photoacoustic amplitude scales up with optical absorption reaching 11 MPa at ~ 228 mJ/cm$^2$ laser fluence. We observed a deviation of the pressure amplitude from the linearity increasing the laser fluence, which indicates a decrease of the Grüneisen parameter. Spatial confinement of high amplitude (> 40 MPa, laser fluence > 55 mJ/cm$^2$) and high frequency (Bw-6db ~ 21.5 MHz) ultrasound was achieved by embedding the freestanding film in an optical lens. The acoustic gain promotes the formation of cavitation microbubbles for moderate fluence in water and in tissue-mimicking material. Our results pave the way for novel photoacoustic medical devices and integrated components.

Keywords

kompoziti;fotoakustični materiali;laserski ultrazvoki;fotoakustične leče;akustična kavitacija;ultrasonic photoacoustic composite;photoacoustic materials;laser ultrasonics;photoacoustic lens;acoustic cavitation;

Data

Language: English
Year of publishing:
Typology: 1.01 - Original Scientific Article
Organization: UL FS - Faculty of Mechanical Engineering
UDC: 534
COBISS: 126257667 Link will open in a new window
ISSN: 2213-5979
Views: 310
Downloads: 124
Average score: 0 (0 votes)
Metadata: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Other data

Secondary language: Slovenian
Secondary keywords: kompoziti;fotoakustični materiali;laserski ultrazvoki;fotoakustične leče;akustična kavitacija;
Type (COBISS): Article
Pages: str. 1-10
Issue: ǂVol. ǂ28
Chronology: Dec. 2022
DOI: 10.1016/j.pacs.2022.100413
ID: 16800860