A. A. Bubnov, A. V. Syuy, V. Yu. Timoshenko
- Institute for Physics and Engineering in Biomedicine, National Research Nuclear University MEPhI, 115409, Moscow, Russia
- Center for Photonics and Two-Dimensional Materials, Moscow Institute of Physics and Technology (National Research University), 141700, Dolgoprudnyi, Moscow oblast, Russia
- Faculty of Physics, Lomonosov Moscow State University, 119991, Moscow, Russia
Abstract: We report an experimental study of optical and photothermal properties of aqueous suspensions of titanium nitride (TiN) nanoparticles (NPs), exhibiting plasmon resonance in the visible and near-IR spectral regions. Dependences of the rate of photoinduced heating and the value of photothermal conversion efficiency (PCE) on the concentration of TiN NPs are obtained for exciting laser wavelengths of 532, 665, and 808 nm. It is found that under irradiation at 808 nm, the PCE is 1.5–2.5 times greater than that under irradiation in the visible range of the spectrum, and for all studied laser wavelengths, an increase in the PCE is observed with increasing NP concentration, reaching a value of 0.55 for an NP concentration on the order of 1 mg/ml under irradiation at a wavelength of 808 nm. The concentration dependence of the PCE is explained by the contribution of multiple scattering in combination with light absorption in ensembles of TiN NPs. The results may be useful for biomedical applications of TiN NPs in the method of local photohyperthermia under multifrequency laser excitation.
Keywords: photohyperthermia, photothermal conversion efficiency, localized plasmon resonance, nanoparticles, titanium nitride.
The photoheating study was supported by a grant from the Innovation Promotion Fund under the UMNIK-21 program based on agreement no. 17260GU/2022 dated April 11, 2022. The TEM studies were supported by a grant from the Russian Science Foundation (agreement no. 22-19-00094). This work was supported by the Ministry of Science and Higher Education of the Russian Federation (no. FSMG-2021-0005).
Received: 19.07.2023
Revised: 10.01.2024
Accepted: 01.02.2024