Highly Sensitive, Multiparametric Thermal History Phosphor Based on An Eu(BTC) Architecture

The capacity to discern the highest temperature that an object is subjected to is a crucial diagnostic tool. Consequently, the pursuit of materials that enable the luminescence-based investigation of the thermal history of an object with high sensitivity is of great importance from the functional applications standpoint. This study aims to present a multiparametric thermal history phosphor based on the luminescent coordination polymer [Eu(BTC)(H2O)6] [Eu(BTC)-1, where H3BTC = 1,3,5-benzenetricarboxylic acid]. The progressive dehydration that Eu(BTC)-1 undergoes as a function of temperature increase in the 343-425 K range results in significant alterations in both the shape of the Eu3+ ions emission spectrum and the depopulation kinetics of their 5D0 level. Based on this occurrence, a thermal history phosphor with an unprecedentedly high relative sensitivity of 11.3% K-1 in ratiometric mode, and 1.8% K-1 in lifetime-based mode, is developed. The outcomes of this research are expected to stimulate a wide interest in the exploitation of (porous) coordination polymer-type materials for the development of thermal history phosphors.The thermally-induced dehydration process of the [Eu(BTC)(H2O)6] coordination polymer results in a modification of the spectroscopic properties of the Eu3+ ion. This modification facilitates the development of a ratiometric and lifetime-based thermal history phosphor, exhibiting the highest relative sensitivity reported to date.