A Novel near white light emitting nanocrystalline Zn2P2O7:Sm~(3+) derived using citrate precursor route: Photoluminescence spectroscopy

摘要

Nanocrystalline Zn2P2O7:Sm~(3+) was synthesized using citrate precursor route. Rietveld refined XRD shown the formation of pure phase at 900 °C. Based on scanning electron microscopy, size distribution of the pyrophosphate particle was found to be in the range of 50-100 nm. Upon near UV light excitation (403 nm), Zn2P2O7:Sm~(3+)exhibits host emission at 450 nm along with characteristic emission lines of Sm~(3+). Based on PL decay measurement, it was inferred that two different types of Sm~(3+) ions were present in the zinc pyrophosphate. The first type was a short lived species (~τ = 100 us) present at less symmetric '5-coordinated Zn' sites, while the second was a long lived species (~τ = 1.9 ms) present at symmetric '6-coordinated Zn' sites. The color coordinates of the system were evaluated using CIE index diagram to be 0.36 and 0.37, which suggest that the prepared material is a potential near white light emitting phosphor.