Ultrasonic photoacoustic emitter of graphene-nanocomposites film on a flexible substrate

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

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.

• Jezik: Angleški jezik
• Ključne besede: ultrasonic photoacoustic composite, photoacoustic materials, laser ultrasonics, photoacoustic lens, acoustic cavitation, graphene-polydimethylsiloxane composite
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FS - Fakulteta za strojništvo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2022
• Št. strani: 10 str.
• Številčenje: Vol. 28, art. 100413
• PID: 20.500.12556/RUL-142079
• UDK: 534
• ISSN pri članku: 2213-5979
• DOI: 10.1016/j.pacs.2022.100413
• COBISS.SI-ID: 126257667
• Datum objave v RUL: 19.10.2022

Gradivo je del revije

• Naslov: Photoacoustics
• Založnik: Elsevier
• ISSN: 2213-5979
• COBISS.SI-ID: 519718169

Licence

• Licenca: CC BY-NC-ND 4.0, Creative Commons Priznanje avtorstva-Nekomercialno-Brez predelav 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by-nc-nd/4.0/deed.sl
• Opis: Najbolj omejujoča licenca Creative Commons. Uporabniki lahko prenesejo in delijo delo v nekomercialne namene in ga ne smejo uporabiti za nobene druge namene.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: kompoziti, fotoakustični materiali, laserski ultrazvoki, fotoakustične leče, akustična kavitacija