Studies on photo- and thermal stability of PVA-encapsulated Mn-doped ZnS nanoparticles

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2016-04, Vol.122 (4), p.1-6, Article 292
• Main Authors: Venkataramana, Savadana, Ramanaiah, K., Sarcar, M. M. M.
• Format: Article
• Language: English
• Subjects: Absorbance; Blue shift; Characterization and Evaluation of Materials; Condensed Matter Physics; Fluorescence; Machines; Manufacturing; Materials science; Nanoparticles; Nanotechnology; Optical and Electronic Materials; Physics; Physics and Astronomy; Processes; Quantum dots; Surfaces and Interfaces; Thin Films; Transmission electron microscopy; Zinc sulfides
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-016-9882-4

In this study, an aqueous-based synthesis route has been developed to prepare highly luminescent polyvinyl alcohol (PVA)-capped manganese-doped ZnS quantum dots (QDs). The QDs showed markedly blue shift in their optical absorbance, indicating strong quantum size effect and the average diameter of the QDs calculated ~3 nm. The QDs showed high-intensity Mn 2+ -related orange luminescence at 585 nm with a very low-intensity peak at 430 nm for the surface defect states. X-ray powder diffraction, transmission electron microscopy, UV–visible spectroscopy and spectrofluorometry have been used to characterize the doped QDs. Studies on the thermal and photochemical stability of the photoluminescence properties are carried out, which showed that after 5 h of photoexcitation and 30 min of 70 °C treatments, the nanoparticles retain almost 40 % of their initial quantum yield. Our systematic investigation shows that these PVA-capped Mn:ZnS QDs may be used as fluorescent labels in biological applications.