Particle size effects of nano- and polycrystalline metal tungstate MWO4 (M = Ca, Pb, Cd) scintillators were examined
through a comparison of commercially available powders and solution precipitation prepared nanoscaled materials. The
scintillation behaviors of nanoparticles and commercial powders were examined with ion beam induced luminescence
(IBIL), photoluminescence (PL), and cathodoluminescence (CL) spectroscopy techniques. For commercial microns
sized MWO4 powders, spectral emission differences between CL and PL were only observed for Cd and Pb tungstates
when compared to reported single crystals. The IBIL wavelength emissions also differed from the commercial MWO4
CL and PL data and were red shifted by 28 and 14 nm for CaWO4 and CdWO4; respectively, while PbWO4 had no
significant change. IBIL analysis on CaWO4 nanoparticles produced a 40 nm blue shift from the commercial powder
emission. These preliminary results suggest that both size and cation Z may affect the emission properties of the MWO4
scintillators.
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