Preparation And Research Of Thin Film Temperature Sensor Based On Triaryl Phosphorus Oxide Derivatives

Temperature is a physical property that quantitatively expresses the common notions of hot and cold,and has important significance in various fields including daily life,industry,science and technology.The fluorescent temperature sensor based on small organic molecules has attracted the attention of researchers due to its simple synthesis and low cost.However,the fluorescence intensity of the organic fluorescent compound greatly decreases due to the increase in the non-radiative transition as the temperature increases,therefore,it is difficult to achieve the detection of wide range,gradient thermal sensitivity and large area thermal mapping.So a series of high temperature resistant organic blue fluorescence materials was used to prepare ratio-type fluorescence temperature-sensitive thin films by mixing with yellow fluorescence materials in this paper,it could be applied to temperature measurement of high temperature,large range and gradient thermal map.The specific research contents are as follows:（1）The photophysical properties of five blue fluorescent compounds based on triarylphosphine oxide structures were investigated in a transparent polymer matrix,and the temperature-dependent spectra of their solid films were explored.The five small molecule fluorescent films maintain a relatively slow fluorescence decay rate with increasing temperature due to the presence of thermally induced"highlight"excited states that compete with thermally induced non-radiative inactivation.（2）Based on the above-mentioned pyrrole-pyrene group-based triarylphosphorus structure compounds,a series of ratio-type fluorescent temperature sensing films were prepared by introducing an ESIPT yellow light compound with large Stokes shift and AIE properties.The C1/T4AC hydred film maintains good stability and reversibility at a high temperature of 200℃,and the relative sensitivity（Sr）is higher than 1%K^-1 in the temperature range of 139K from 334 K（61℃）to 473 K（200℃）,and Sr reached a maximum of 1.575%K^-1 at 418 K（145℃）,and it was successfully applied to temperature imaging and temperature gradient mapping measurement of different morphologies.（3）Based on the above-mentioned carbazole-pyrene group-based triarylphosphorus compound,a series of ratio-type fluorescent temperature sensing films were prepared by introducing ESIPT yellow light with large Stokes shift and AIE Compound.The maximum relatived sensitivity（Sr）of the thin film temperature sensor is high as 2.14%K^-1,and the relative sensitivity Sr is greater than 1%K^-1 in the range of 66～225℃.The films has a fluorescent color change that is visible to the naked eye with temperature changes.It can be used for temperature measurement of large-area temperature imaging,temperature gradient mapping and fluorescent anti-counterfeiting marks.And the series of temperature sensor films have good stability and reversibility.