Efficient near-infrared quantum cutting by cooperative energy transfer in Bi.sub.3TeBO.sub.9:Nd.sup.3+ phosphors

• Published in: Journal of materials science Vol. 57; no. 1; pp. 185 - 203
• Main Authors: Zhezhera, T, Gluchowski, P, Nowicki, M, Chrunik, M, Majchrowski, A, Kosyl, K. M, Kasprowicz, D
• Format: Journal Article
• Language: English
• Published: Springer 01.01.2022
• Subjects: Analysis; Powders; Radiation
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-021-06642-2

An efficient near-infrared quantum cutting process by cooperative down-conversion of active Bi.sup.3+ and Nd.sup.3+ ions was demonstrated in Bi.sub.3TeBO.sub.9:Nd.sup.3+ phosphors. In particular, the near-infrared emission of Nd.sup.3+ ions enhanced by Bi.sup.3+ ions of a series of novel Bi.sub.3TeBO.sub.9:Nd.sup.3+ microcrystalline powders doped with Nd.sup.3+ ions in various concentrations was investigated. In order to investigate the luminescent properties of BTBO:Nd.sup.3+ powders, the excitation and emission spectra and the fluorescence decay time were measured and analyzed. In particular, the emission of Bi.sub.3TeBO.sub.9:Nd.sup.3+ at 890 and 1064 nm was excited at 327 nm (via energy transfer from Bi.sup.3+ ions) and at 586.4 nm (directly by Nd.sup.3+ ions). The highest intensity emission bands in near-infrared were detected in the spectra of Bi.sub.3TeBO.sub.9:Nd.sup.3+ doped with 5.0 and 0.5 at.% of Nd.sup.3+ ions upon excitation in ultraviolet and visible spectral range, respectively. The fluorescence decay lifetime monitored at 1064 nm for Bi.sub.3TeBO.sub.9:Nd.sup.3+ powders shows the single- or double-exponential character depending on the concentrations of Nd.sup.3+ ions. The possible mechanisms of energy relaxation after excitation Bi.sub.3TeBO.sub.9:Nd.sup.3+ powders in ultraviolet or visible spectral range were discussed. The investigated Bi.sub.3TeBO.sub.9:Nd.sup.3+ phosphors efficiently concentrate the ultraviolet/visible radiation in the near-infrared spectral range and can be potentially used as effective spectral converters.