Spectroscopic Signatures of Sub-Second Laser-Calcined Dy3+-Doped Oxide Precursors for Use in ex Situ Thermal Impulse Sensors

5 years ago

Spectroscopic Signatures of Sub-Second Laser-Calcined Dy3+-Doped Oxide Precursors for Use in ex Situ Thermal Impulse Sensors

Hergen Eilers, Benjamin R Anderson, Ray Gunawidjaja

We measure the phase-dependent spectroscopic signatures—photoluminescence (PL) emission spectrum, PL excitation spectrum, and PL lifetime—of three different heat treated Dy³⁺-doped oxide precursors (TiO₂, Y₂O₃, and ZrO₂), which are calcined at temperatures ranging from 440 to 1256 K for 100 ms. On the basis of these spectroscopic measurements we compute temperature calibration curves, which correlate a given spectroscopic signature to a specific calcination temperature. We find that the emission/excitation spectra-based calibration curves for a given material, in general, have the same transition temperature within uncertainty, but the lifetime-based calibration curve is found to transition at a lower temperature. This difference is due to the emission/excitation-based curves depending on crystallization of the oxide hosts, while the lifetime changes due to the decomposition of the precursor compound, which eliminates some PL quenchers, including high energy O–H, C–O, and C–O₂ vibrations. The observation of two different kinetic phenomenon in a single oxide host has promising applications in ex situ thermal impulse sensors, which have uses in explosive fireballs, combustion science, and arson investigations.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b06692

DOI: 10.1021/acs.jpcc.7b06692