Author, as appears in the article.: Nexha A; Pujol MC; Carvajal JJ; Díaz F; Aguiló M

Department: Química Física i Inorgànica

e-ISSN: 2079-4991

URV's Author/s: Aguiló Díaz, Magdalena / Carvajal Martí, Joan Josep / Díaz González, Francisco Manuel / Nexha, Albenc / Pujol Baiges, Maria Cinta

Keywords: Third biological window spectral regime Solvothermal synthesis Photothermal conversion efficiency Nanocrystals Monoclinic double tungstates Luminescence nanothermometry Luminescence nan-othermometry

Abstract: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. The incorporation of oleic acid and oleylamine, acting as organic surfactant coatings for a novel solvothermal synthesis procedure, resulted in the formation of monoclinic KLu(WO4)2 nano-crystals. The formation of this crystalline phase was confirmed structurally from X-ray powder dif-fraction patterns and Raman vibrational modes, and thermally by differential thermal analysis. The transmission electron microscopy images confirm the nanodimensional size (~12 nm and ~16 nm for microwave-assisted and conventional autoclave solvothermal synthesis) of the particles and no agglomeration, contrary to the traditional modified sol-gel Pechini methodology. Upon doping with holmium (III) and thulium (III) lanthanide ions, these nanocrystals can generate simultaneously photoluminescence and heat, acting as nanothermometers and as photothermal agents in the third biological window, i.e., self-assessed photothermal agents, upon excitation with 808 nm near infra-red, lying in the first biological window. The emissions of these nanocrystals, regardless of the sol-vothermal synthetic methodology applied to synthesize them, are located at 1.45 μm, 1.8 μm and 1.96 μm, attributed to the3H4 →3F4 and3F4 →3H6 electronic transition of Tm3+ and5I7 →5I8 electronic transition of Ho3+, respectively. The self-assessing properties of these nanocrystals are studied as a function of their size and shape and compared to the ones prepared by the modified sol-gel Pechini methodology, revealing that the small nanocrystals obtained by the hydrothermal methods have the ability to generate heat more efficiently, but their capacity to sense temperature is not as good as that of the nanoparticles prepared by the modified sol-gel Pechnini method, revealing that the synthesis method influences the performance of these self-assessed photothermal agents. The self-assessing ability of these nanocrystals in the third biological window is proven via an ex-vivo experiment, achieving thermal knowledge and heat generation at a maximum penetration depth of 2 mm.

Thematic Areas: Physics, applied Nanoscience & nanotechnology Materials science, multidisciplinary Materials science (miscellaneous) Materials science (all) General materials science General chemical engineering Engenharias ii Chemistry, multidisciplinary Chemical engineering (miscellaneous) Chemical engineering (all)

licence for use: https://creativecommons.org/licenses/by/3.0/es/

Author's mail: f.diaz@urv.cat mariacinta.pujol@urv.cat magdalena.aguilo@urv.cat joanjosep.carvajal@urv.cat

Author identifier: 0000-0003-4581-4967 0000-0002-1052-8031 0000-0001-6130-9579 0000-0002-4389-7298

Record's date: 2023-09-23

Papper version: info:eu-repo/semantics/publishedVersion

Link to the original source: https://www.mdpi.com/2079-4991/11/2/485

Licence document URL: http://repositori.urv.cat/ca/proteccio-de-dades/

Papper original source: Nanomaterials. 11 (2): 1-29

APA: Nexha A; Pujol MC; Carvajal JJ; Díaz F; Aguiló M (2021). Effect of the size and shape of Ho, Tm:KLu(WO4)2 nanoparticles on their self-assessed photothermal properties. Nanomaterials, 11(2), 1-29. DOI: 10.3390/nano11020485

Article's DOI: 10.3390/nano11020485

Entity: Universitat Rovira i Virgili

Journal publication year: 2021

Publication Type: Journal Publications