Testing nanocrystalline CdWO4 doped with Yb3+ as a possible down-conversion phosphor. (July 2016)

• Record Type: Journal Article
• Authors: Vanetsev, A.S.; Orlovskii, Yu.V.; Nagirnyi, V.; Sildos, I.; Puust, L.; Kaldvee, K.; Yin, M.; Wei, X.T.; Makhov, V.N.
• Is Part Of: Radiation measurements. Volume 90(2016:Jul.)
• Page Start: 329
• Page End: 333
• Publication Date: 2016-07
• Subjects: Down-conversion -- Cooperative energy transfer -- Nanophosphor -- Microwave-hydrothermal synthesis -- CdWO4:Yb3+ -- Solar cell; Nuclear emulsions -- Periodicals; Particle tracks (Nuclear physics) -- Periodicals; Thermoluminescence -- Periodicals; Cosmic rays -- Periodicals; Radiation -- Measurement -- Periodicals; Radiometry -- Periodicals; Radiation Monitoring -- Periodicals; Émulsions nucléaires -- Périodiques; Particules (Physique nucléaire) -- Traces -- Périodiques; Thermoluminescence -- Périodiques; Rayonnement cosmique -- Périodiques; Radiométrie -- Périodiques; 539.77
• DOI: 10.1016/j.radmeas.2016.01.009
• Languages: English
• ISSNs: 1350-4487

Abstract

Abstract: The CdWO4 :Yb 3+ (0.1, 2, 3%) nanophosphors have been synthesized using microwave-hydrothermal treatment. The spectral and kinetic characteristics of their luminescence were studied with the aim to check the possibility of cooperative energy transfer from CdWO4 self-trapped excitons to Yb 3+ pairs, which can provide down-conversion of UV photons absorbed by the CdWO4 host into two lower-energy (IR) photons emitted by two Yb 3+ ions. The obtained results have shown the conversion of absorbed UV photons into Yb 3+ IR fluorescence. However, the obtained parameters of decay kinetics of both intrinsic luminescence of CdWO4 and IR fluorescence of Yb 3+ did not confirm the existence of cooperative energy transfer from STE to two Yb 3+ ions in the studied CdWO4 :Yb 3+ nanophosphors. The reason is supposed to be rather low concentrations of Yb 3+ obtained in the synthesized samples which prevents the creation of high enough concentration of Yb 3+ pairs with short distances between the ions. Highlights: CdWO4 :Yb 3+ nanophosphors were synthesized by microwave-hydrothermal method. Efficient conversion of absorbed UV photons into Yb 3+ IR fluorescence was detected. Excitonic PL quenching kinetics is compared with the model of cooperative quenching. The quenching kinetics contradicts the existence of cooperative down-conversion.