Versatility of thermoluminescence materials in thermal history sensing: a review

While several devices can monitor temperature, measuring non-volatile thermal history is far more challenging, especially for sensors placed in hazardous settings like fires and explosions. Herein, the utilisation of thermoluminescent microparticles in thermal history sensors is discussed. These transparent dielectric microparticles can store charge carriers for very extended periods due to their wide distribution of trap states. In its most basic form, an Arrhenius expression is strongly temperature-dependent for determining the population of the trap states. When exposed to high temperatures for a brief period, a particle with filled traps will preferentially lose carriers in shallow traps. To ascertain the temperature and timing of the thermal event, this depopulation creates a mark on the particle luminescence. By being exposed to deep ultraviolet, X-ray, beta, or gamma radiation, which fills the traps with charge carriers, particles are prepared many months before a test, if required. No matter if they are embedded in garbage or other inert materials, one or more particles can nevertheless be made to emit light. Laboratory tests using microheaters and high-energy explosives in the field are used to test and analyse the technology. It is demonstrated that a variety of high-explosive conditions may be used to accurately detect temperatures in the $ 200\mathrm{<^>\circ C} $ 200 circle C to $ 500\mathrm{<^>\circ C} $ 500 circle C range using thermoluminescent materials like LiF:Mg,Ti, MgB4O7:Dy,Li, and CaSO4:Ce,Tb. The article will provide the utilisation of different luminescent materials for sensing thermal history and analysing the particle luminescence mechanism through different thermal models for developing improved thermal history sensing technologies. The thermal history reconstruction techniques are also discussed to predict the thermal history. Therefore, the article will pave the way to understanding the luminescent properties of thermoluminescent microparticles for developing state-of-the-art thermal history sensors for measuring non-volatile thermal history and temperature in extreme environments such as fires and explosions.