Determination of particle size distribution of water-soluble CdTe quantum dots by optical spectroscopy

Autor(es)

Sousa, J. C. L. ^[1] ; Vivas, M. G. ^{[2, 3]} ; Ferrari, J. L. ^[1] ; Mendonca, C. R. ^[2] ; Schiavon, M. A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Joao del Rei, Dept Ciencias Nat, GPQM, BR-36301160 Sao Joao Del Rei, MG - Brazil

^[2] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

^[3] Univ Fed Alfenas, Inst Ciencia & Tecnol, BR-37715400 Pocos De Caldas, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: RSC ADVANCES; v. 4, n. 68, p. 36024-36030, 2014.
• Citações Web of Science: 13

Resumo

In the present study, we report the synthesis of glutathione (GSH) capped CdTe quantum dots (QDs) using the one-pot approach as well as their optical properties. These QDs were used as a probe for a detailed quantitative correlation between spectroscopic data and QDs size dispersion. We have developed a spectroscopic method to determine the size dispersion of QDs in solution based on the fluorescence spectroscopy and the fluorescence quantum yields. Our results demonstrate that the one-pot approach produces GSH-capped CdTe QDs of narrow size dispersion, as inferred by the sharp line width (full width at half maximum) of the fluorescence signal (from 153 meV to 163 meV), as revealed by our spectroscopy method. We observed that the GSH-capped CdTe QDs cause an increase in fluorescence quantum yield from 11% to 30% concomitantly with an increase in lifetime decay from 38 to 50 ns during the course of synthesis (from 15 min to 120 min), indicating an increase in the average size of the QDs. Finally, we have used the evolving factor analysis together with the multivariate curve resolution-alternating least squares method to corroborate our results, and we found a good agreement between both methods with the advantage that in our method, we were able to obtain size dispersion rather than just the mean QD size. (AU)

• Processo FAPESP: 09/11810-8 - Estudo do efeito de solvente sobre os espectros da absorção de um e dois fótons de moléculas orgânicas conjugadas.
• Beneficiário: Daniel Luiz da Silva
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 11/12399-0 - Aplicações de pulsos de femtossegundos em óptica não linear: espectroscopia, formatação de pulsos e microfabricação
• Beneficiário: Cleber Renato Mendonça
• Modalidade de apoio: Auxílio à Pesquisa - Temático