Khan Muhammad Shaukat, Farooq Hunain, Wittmund Christopher, Klimke Stephen, Lachmayer Roland, Renz Franz, Roth Bernhard
Hannover Centre for Optical Technologies, Leibniz University Hannover, 30167 Hannover, Germany.
Institute for Inorganic Chemistry, Leibniz University Hannover, 30167 Hannover, Germany.
Polymers (Basel). 2021 Jan 7;13(2):195. doi: 10.3390/polym13020195.
We report on a polymer-waveguide-based temperature sensing system relying on switchable molecular complexes. The polymer waveguide cladding is fabricated using a maskless lithographic optical system and replicated onto polymer material (i.e., PMMA) using a hot embossing device. An iron-amino-triazole molecular complex material (i.e., Fe(Htrz)(NH-trz)) is used to sense changes in ambient temperature. For this purpose, the core of the waveguide is filled with a mixture of core material (NOA68), and the molecular complex using doctor blading and UV curing is applied for solidification. The absorption spectrum of the molecular complex in the UV/VIS light range features two prominent absorption bands in the low-spin state. As temperature approaches room temperature, a spin-crossover transition occurs, and the molecular complex changes its color (i.e. spectral properties) from violet-pink to white. The measurement of the optical power transmitted through the waveguide as a function of temperature exhibits a memory effect with a hysteresis width of approx. 12 °C and sensitivity of 0.08 mW/°C. This enables optical rather than electronic temperature detection in environments where electromagnetic interference might influence the measurements.
我们报道了一种基于聚合物波导的温度传感系统，该系统依赖于可切换的分子复合物。聚合物波导包层是使用无掩膜光刻光学系统制造的，并使用热压印设备复制到聚合物材料（即聚甲基丙烯酸甲酯）上。一种铁 - 氨基 - 三唑分子复合物材料（即Fe(Htrz)(NH - trz)）用于感知环境温度的变化。为此，波导的芯部填充有芯材（NOA68）的混合物，并使用刮刀涂覆和紫外线固化将分子复合物固化。分子复合物在紫外/可见光范围内的吸收光谱在低自旋态下有两个突出的吸收带。当温度接近室温时，会发生自旋交叉转变，分子复合物的颜色（即光谱特性）从紫粉色变为白色。测量通过波导传输的光功率随温度的变化呈现出记忆效应，滞后宽度约为12°C，灵敏度为0.08 mW/°C。这使得在电磁干扰可能影响测量的环境中能够进行光学而非电子温度检测。
