Autor(es)

Pereira, Tayne P. ; Canisares, Felipe S. M. ; Marques, Leandro R. ; Ando, Romulo A. ; Brito, Hermi F. ; Bispo-Jr, Airton G.

• Tipo de documento: Artigo Científico
• Fonte: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY; v. 348, p. 9-pg., 2026-11-19.

Resumo

Optical temperature sensing plays an essential role in monitoring a variety of chemical, physical, and biological processes. Among several techniques, Raman thermometry enables structural insight through vibrational modes, whereas luminescence thermometry offers high thermal sensitivity. Lanthanide(III) (LnIII) coordination compounds are among the most extensively studied systems for the development of optical temperature probes, particularly within the framework of self-calibrated ratiometric approaches. However, achieving superior thermal sensitivity in ratiometric Raman-based systems remains a significant challenge. Furthermore, bright single-centered LnIII luminescent probes typically exhibit limited thermal sensitivity when relying solely on ratiometric approaches. Herein, we report a hybrid optical thermometer that combines Raman and luminescence bands within a single Raman spectrum to calculate a ratiometric thermometric parameter (Delta = Iluminescence/IRaman). This optical feature is achieved by incorporating the [Eu(nta)3(phen)] (nta: 4,4,4-trifluoro-1-(2-naphthyl)-1,3-buta-dione; phen: 1,10-Phenanthroline) complex into a poly(methyl methacrylate) (PMMA) matrix, fabricating transparent and homogeneous films that allow simultaneous detection of PMMA vibrations and EuIII intraconfigurational 4f6emissions in the same Raman spectrum. Raman measurements from 100 to 420 K reveal two distinct temperature-dependent regimes of the thermometric parameter: a Raman-dominated exponential response below 280 K (maximum relative thermal sensitivity, Sm, of 1.1 % K-1 at 280 K), and a luminescence-driven response above 280 K (Sm of 5.2 % K-1 at 420 K). The thermometric parameter remained stable over nine heating-cooling cycles (100-420 K), confirming its robust repeatability. Therefore, the ratiometric approach based on luminescence and Raman bands offers a versatile platform with operational flexibility for developing highly sensitive temperature probes based on EuIII coordination compounds. (AU)

• Processo FAPESP: 23/16684-8 - Plataformas multifuncionais compostas por híbridos inorgânico-orgânico UCNPS@SiO2-Ln3+-Ir3+ para sensoriamento, imageamento celular e geração de oxigênio singleto pelo processo de upconversion
• Beneficiário: Felipe da Silva Manrique Canisares
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 25/04765-9 - Filmes Poliméricos Luminescentes com Codificação Espectral e Temporal para Segurança Avançada contra Falsificação
• Beneficiário: Tayne Paranhos Pereira
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• 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
• Processo FAPESP: 22/11983-4 - Espectroscopias com intensificação de sinal: nanomateriais, teoria e simulação computacional
• Beneficiário: Mauro Carlos Costa Ribeiro
• Modalidade de apoio: Auxílio à Pesquisa - Temático