NIR Luminescence Enhancement of YVO4:Nd Phosphor for Biological Application

Autor(es)

Tanaka, Julio Tadashi ^[1] ; Moscardini, Susane Bonamin ^[1] ; do Nascimento Melo, Willian Euripedes ^[1] ; Brunckova, Helena ^[2] ; Nassar, Eduardo Jose ^[1] ; Rocha, Lucas Alonso ^[1]

Afiliação do(s) autor(es)

^[1] Univ Franca, Ave Dr Armando Salles Oliveira 201, BR-14404600 Franca, SP - Brazil

^[2] Slovak Acad Sci, Inst Mat Res, Watsonova 47, Kosice 04001 - Slovakia

• Tipo de documento: Artigo Científico
• Fonte: Journal of Fluorescence; v. 31, n. 1 NOV 2020.
• Citações Web of Science: 0

Resumo

This work reports two systematic studies related to yttrium vanadate (YVO4) phosphors. The first evaluates how the annealing temperature and V5+/Y3+ molar ratio determine the emergence of a single YVO4 tetragonal phase, whereas the second concerns the optimal Nd3+ concentration to improve the infrared emission properties for bio-labelling applications. The YVO4:Nd phosphors were synthesized by adapting the non-hydrolytic sol-gel route. For the first study, samples containing different V5+/Y3+ molar ratios (1.02, 1.48, 1.71, or 3.13) were obtained. For the second study, YVO4:Nd phosphors containing different Nd3+ concentrations (1.0, 3.0, 5.0, or 10.0% in mol) were prepared. X-ray diffractometry and RAMAN spectroscopy results revealed that, regardless of the heat-treatment temperature, the V5+/Y3+ molar ratio of 1.48 was the best composition to avoid undesired phases like Y2O3 and V2O5. Photoluminescence results indicated that the sample containing 3.0% in mol of Nd3+ and annealed at 1000 degrees C presented the best infrared emission properties. This sample displayed an intense broad band in the ultraviolet region, which was ascribed to the VO43- charge transfer band, as well as several bands in the visible and infrared regions, which were attributed to the Nd3+ intraconfigurational f-f transitions. Regardless of the excitation wavelength (ultraviolet, visible, or near-infrared), the mean radiative lifetime was about 12.00 mu s. The prepared phosphors presented absorption and emission bands in the biological window (BW) regions, which are located between 750 and 900 nm and between 1000 and 1300 nm, so they are candidates for applications in medical imaging and diagnoses. (AU)

• Processo FAPESP: 11/09823-4 - Utilização do íon európio III para desvendar estruturas de matrizes obtidas via metodologia sol-gel
• Beneficiário: Eduardo José Nassar
• Modalidade de apoio: Auxílio à Pesquisa - Regular