| Texto completo | |
| Autor(es): |
Borges, Fernanda Hediger
;
Mauricot, Robert
;
Neumeyer, David
;
de Souza, Vitor dos Santos
;
Verelst, Marc
;
Goncalves, Rogeria Rocha
Número total de Autores: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of Luminescence; v. 273, p. 12-pg., 2024-05-11. |
| Resumo | |
We synthesized Er 3+ and Yb 3+ co -doped tantalum oxide (Ta 2 O 5 ) spherical sub -micrometric particles by a facile method involving formation of tantalum glycolates after pouring in acetone. Then, we investigated how the annealing temperature and Yb 3+ concentration (0-30 mol %) affect their structural and luminescence properties. Particle sizes ranged from 146 to 258 nm for the samples annealed at 800 degrees C. XRD analysis revealed the orthorhombic L-Ta 2 O 5 crystalline structure. The different symmetry sites that the rare earth ions can occupy within the Ta 2 O 5 structure led to intense and broad emission bands centered around 1530 nm. Up -conversion measurements and the calculated number of photons for intense green and red emissions obtained with 980 and 1550 nm excitations helped us to elucidate the mechanisms involved at both excitation wavelengths. We investigated how the 0.5 mol % Er 3+ /1.5 mol % Yb 3+ co -doped Ta 2 O 5 sample performs as a primary thermometer by using the Boltzmann distribution law to predict the absolute temperature from the ratio between the Er 3+ 2 H 11/2 -> 4 I 15/2 and 4 S 3/2 -> 4 I 15/2 transitions. We obtained a maximum relative thermal sensitivity of 0.97 +/- 0.04 % K -1 and a minimum delta T of 2.41 K. The calculated repeatability was above 95%. These results show that promising nanothermometer based on Ta 2 O 5 with controlled size and morphology can be designed. (AU) | |
| Processo FAPESP: | 20/00277-6 - Desenvolvimento de materiais nanoparticulados de tantalatos de terras raras dopados com íons lantanídeos para aplicações em Fotônica |
| Beneficiário: | Fernanda Hediger Borges Ribeiro |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| Processo FAPESP: | 20/05319-9 - Plataformas multifuncionais a base de materiais nanoestruturados luminescentes dopados com íons lantanídeos com potencial aplicação em fotônica e teranóstica |
| Beneficiário: | Rogéria Rocha Gonçalves |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 23/13509-0 - Desenvolvimento de tantalatos de terras raras dopados com íons lantanídeos para bioimagem multimodal e nanotermometria |
| Beneficiário: | Fernanda Hediger Borges Ribeiro |
| Modalidade de apoio: | Bolsas no Exterior - Estágio de Pesquisa - Doutorado |
| Processo FAPESP: | 21/08111-2 - Materiais conversores de luz à base de terras raras: marcadores luminescentes, sensores e amplificadores ópticos |
| Beneficiário: | Hermi Felinto de Brito |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |