Nanoparticle-based Scintillating Aerogels for Real-time Radioactive Gas Detection
Résumé
INTRODUCTION
The measurement of pure β emitting radioactive gases such as 3H and 85Kr is already of major importance for the nuclear safety authorities, and will meet an increasing demand with the expansion of nuclear-based energy production. Due to the short penetration length of β electrons in air, gaseous β emitters must be mixed with radiosensitive elements to enable detection. These are either gas-gas mixtures in an ionization chamber, or gas-liquid mixtures in liquid scintillation. However, none of these existing methods combine real-time analysis, sensitivity to multiple gases, and ease of deployment for on-site measurements. We demonstrate a new gas-solid mixture approach using inorganic aerogels as nanoporous scintillators.
EXPERIMENTAL STUDY
This presentation will focus on the preparation of scintillating aerogels. Scintillating nanoparticles were synthesized in the 10g-scale via a solvothermal route. After extensive washing, a controlled aggregation procedure allowed for their assembly into gels. These gels were then dried into transparent aerogels in supercritical CO2. The aerogels were then exposed to known quantities of radioactive gases and their scintillation was measured. The procedure was initially developed to produce Ce4+:YAG nanoparticles aerogels, and was subsequently applied to other scintillating nanomaterials.
RESULTS AND DISCUSSION
Transparent scintillating aerogels were obtained by the same method for Ce4+:YAG and other nanomaterials. Statistical treatment of their measured scintillation allowed efficient, real-time measurement of 3H and 85Kr activity.
Mots clés
instrumentation
nuclear instrumentation
radioactivity
ionizing radiation
metrology
radioactive gas
beta-rays
3H
85Kr
short penetration length
electrons
beta emitter
detector
porous scintillator
ionization chamber
liquid scintillation counting
sensitivity
aerogel
nano-scintillator
scintillating aerogel
nanoparticle
controlled aggregation procedure
transparent
supercritical drying
scintillation properties