CC BY
5*
ALT'23
The 30th International Conference on Advanced Laser Technologies
LM-P-6
Photothermal response of colloidal solutions based on substoichiometric molybdenum oxide
A. Chernikov, D. Kochuev, R. Chkalov, D. Abramov, K. Khorkov
Institute of Applied Mathematics, Physics and Computer Science, Vladimir State University, Gorky Street, 87, 600000, Vladimir, Russia
email address: [email protected]
In this paper, we present the results of measuring the photosensitized properties of colloidal solutions of nanoparticles based on substoichiometric molybdenum oxide. These solutions were obtained using the techniques of femtosecond laser ablation and fragmentation of molybdenum disulfide in liquid [1, 2]. The experiments were carried out on a laser robotic complex based on the Yb:KGW femtosecond laser system (Avesta Ltd.), generating pulses with a duration of 280 fs at a wavelength of 1030 nm with a repetition frequency of 10 kHz and a maximum pulse energy of 150 J
Measurement of the photosensitivity properties of colloidal systems was carried out on this laboratory stand. We used laser radiation from a continuous diode laser source with a wavelength of 800 nm and an average laser radiation power of 1 W. The use of this laser radiation source is determined based on the spread of application in the areas of therapy, in view of the good permeability of body tissues by radiation with a wavelength of about 800 nm. A collimated laser beam with a cross section in the form of a parallelepiped with sides of 1x3.5 mm was directed to the surface of a quartz test tube for spectrophotometry of the QS grade, 5 ml in volume, with a wall thickness of 1 mm. The investigated colloidal solution was contained inside the quartz test tube. The attenuated laser beam leaving the test tube was measured with a power meter. Registration of thermal processes was carried out by a thermal imaging camera from the surface of the wall of a quartz test tube. The spectral sensitivity range of a thermal imaging camera is 8-12 ^m. Measurement of photosensitivity characteristics was carried out during the time required to reach the maximum temperature in the zone of exposure to the laser beam. During the measurement, the time to reach the maximum temperature was recorded, as well as the transmitted laser radiation.
e=0.95 <■
22.7°C[:
MAX:46.0°C MIN:22.7°C 22:43
Wavelength (
Fig. 1. Time dependence of temperature change during irradiation of colloidal solutions by cw IR laser (805 nm, P = 0.88 W); image with thermal imaging camera; absorption spectra of colloidal solutions obtained by laser fragmentation for 30 and 50 minutes in ethanol (black and blue lines)
and after IR laser irradiation for 10 minutes (805 nm) (pink and red lines).
The study of the processes of formation of nanoparticles was carried out at the expense of the grant of the Russian Science Foundation No. 22-79-10348. a
[1] Kurilova, U.E., Chernikov A.S., Kochuev D.A. et al., Physical and Biological Properties of Layers with Nanoparticles Based on Metal Chalcogenides and Titanium Synthesized by Femtosecond Laser Ablation and Fragmentation in Liquid, Journal of Biomedical Photonics & Engineering, vol., 9(2), 020301, (2023)
[2] Chernikov A.S., Tselikov G.I., Gubin M.Y. et al. Tunable optical properties of transition metal dichalcogenide nanoparticles synthesized by femtosecond laser ablation and fragmentation, Journal of Materials Chemistry C, vol. 11(10), pp. 3493-3503 (2023).
