abstract
Flexible coatings with dual capabilities for remote real-time temperature sensing and photothermal conversion have a huge potential in the field of advanced thermal actuated optoelectronic applications. In this work, we demonstrated that plastic free-standing films of Er3+/Yb3+-codoped GeO2-Ta2O5 particles dispersed in poly(methyl methacrylate) (PMMA) having intriguing upconversion high absolute emission quantum yield (similar to 0.1452, excited at 980 nm, 760 W.cm(-2)) can simultaneously operate as photothermal converters and real-time primary thermometers. The emission of the films was studied at the microscale, revealing emission homogeneity detected through surface hyperspectral microscopy. One factor that contributes to the unusually high absolute emission quantum yield, when compared with other oxides-based materials, is the high occurrence (probability) of the shortest Yb-Er distances obtained when the YbTaO4 phase is formed. This, as demonstrated by computational simulations of doping processes, favors the Yb-to-Er energy transfer rates, enhancing the population of the Er3+ emitting levels. Besides, the films combined a relative thermal sensitivity of similar to 1.1% K-1 (at 300 K) with a temperature uncertainty of similar to 0.7 K and a maximum photothermal efficiency of similar to 44%, which permits the prospect of using this material as a coating with photothermal and thermometer functions. Moreover, as an added benefit, the thermal resistance of the composite in PMMA was estimated, yielding a maximum value of 760 +/- 8 K.W-1. This is the first example of an active coating for photothermal conversion with the simultaneous ability to remotely sense temperature that can be explored in NIR-pumped free-space telecommunications without the need of additional optoelectronics devices.
keywords
UP-CONVERSION; CANCER-CELLS; GRAPHENE OXIDE; EFFICIENT ABLATION; ENERGY-TRANSFER; GOLD NANOCAGES; DRUG-DELIVERY; WAVE-GUIDES; NANOPARTICLES; NANOCRYSTALS
subject category
Chemistry; Science & Technology - Other Topics; Materials Science
authors
Caixeta, FJ; Bastos, ARN; Botas, AMP; Rosa, LS; Souza, VS; Borges, FH; Neto, ANC; Ferrier, A; Goldner, P; Carlos, LD; Goncalves, RR; Ferreira, RAS
our authors
Groups
G1 - Porous Materials and Nanosystems
G2 - Photonic, Electronic and Magnetic Materials
G3 - Electrochemical Materials, Interfaces and Coatings
Other
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Mediaacknowledgements
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials (UIDB/50011/2020 and UIDP/50011/2020), financed by national funds through the FCT/MEC and when appropriate cofinanced by FEDER under the PT2020 Partnership through the European Regional Development Fund in the frame of the Operational Competitiveness and Internationalization Programme (POCI). F.J.C. acknowledges CNPq for financial support and FAPESP (grant numbers 2017/10423-7 and 2019/259916) and CAPES (grant number 88881.188839/2018-01-PDSE) for scholarships. A.R.N.B., A.M.P.B., and A.N.C.N. are thankful for the grants financed by the SusPhotoSolutions project (CENTRO-01-0145-FEDER-000005). Marita Cardoso from the University of Aveiro is acknowledged for her help in the film's preparation.