Citation

Anderson BR, Gese N, Gunawidjaja R, Eilers H. Appl. Spectrosc. 2018; 72(9): 1310-1321.

Affiliation

Applied Sciences Laboratory, Institute for Shock Physics, Washington State University, Spokane, WA, USA.

Copyright

(Copyright © 2018, Society for Applied Spectroscopy)

DOI

10.1177/0003702817734292

PMID

29082759

Abstract

We develop nanoscale ex situ thermal impulse (i.e., the temperature and duration of a heating event) sensors for structural fire forensics using a mixture of two lanthanide-doped oxide precursors (precursor Eu:ZrO2 and precursor Dy:Y2O3) that undergo irreversible phase changes when heated. These changes are probed using photoluminescence (PL) spectroscopy with the PL spectra being dependent on the thermal impulse (TI) experienced by the sensors. By correlating the PL spectra to different in-lab TIs, we are able to produce a spectroscopic calibration for our sensors. This calibration allows us to determine an unknown TI of a heating event using only the PL spectrum of the heated TI sensors. In this study, we report on the calibration of these sensors for isothermal heating durations up to 600 s and isothermal temperatures up to 1273 K. Using this calibration, we also demonstrate their ability to determine an unknown TI and demonstrate their functionality when dispersed into paint, which is heated in the presence of drywall.

Language: en

Keywords

Lanthanides; Temperature sensors; arson investigation; irreversible phase changes; lanthanide-doped oxides; photoluminescence spectroscopy; structural fire forensics