In-situ, Remote Query Chemical Sensors Based On Magnetoelastic Thick Films

本提案旨在支持基于独立磁弹性厚膜谐振频率变化的新型远程查询传感器技术的开发和应用。这项工作建立在，补充，并有助于扩展化学传感器为导向的研究的共同pi积极参与。磁弹性传感器是由磁致伸缩、磁弹性的非晶态金属玻璃b[1]组成的带状厚膜。在响应交流磁场时，传感器有效地将磁能转化为弹性能，弹性能反过来使传感器发生机械变形。这种机械变形表现出一种机械共振，其频率与传感器的长度成反比。最近已经证明，磁弹性传感器的谐振频率会随着几个不同的环境参数而变化，包括压力、温度、粘度、面间分子键，而且非常重要的是，当与质量变化的化学反应层化学分析物浓度结合使用时。利用葡萄糖响应聚合物[4]证明了磁弹性传感器在远程查询化学传感中的应用。磁弹性传感器谐振频率的变化已经测量响应于低于0.9 ng/mm2的差异表面质量载荷。本研究选择了三种类型的微孔薄膜，为控制气体进入微孔的吸附和/或吸收提供了广泛的表面化学性质。通过控制孔径和表面化学性质，我们可以调整磁弹性传感器对含有许多不同溶质和溶剂分子的混合物中给定化合物的选择性。

This proposal seeks support for the development and application of a new remote query sensor technology based on changes in the resonant frequency of free-standing magnetoelastic thick films. The work builds upon, complements, and helps extend the chemical sensor oriented research the co-PI's are actively involved with.Magnetoelastic sensors are comprised of ribbon-shaped thick-films of magnetostrictive, magnetoelastic amorphous metallic glass [1]. In response to an ac magnetic field the sensors efficiently translate magnetic energy into elastic energy which, in turn, acts to mechanically deform the sensor. This mechanical deformation demonstrates a mechanical resonance the frequency of which is inversely proportional to the length of the sensor. It has recently been demonstrated [2] that the resonant frequency of a magnetoelastic sensor shifts in response to several different environmental parameters including pressure, temperature, viscosity, inter-facial molecular bond and, very importantly, when used in combination with a mass changing, chemically responsive layer [3] chemical analyte concentrations. Applications of magnetoelastic sensors to remote query chemical sensing has been demonstrated using a glucose responding polymer [4]. Changes in the resonant frequency of a magnetoelastic sensor have been measured in response to differential surface mass loadings below 0.9 ng/mm2. Three types of microporous thin-films were chosen for this study, providing a broad range of surface chemistries for controlling the adsorption and/or absorption of gas into the micropores. By controlling the pore size as well as the surface chemistry, we can tune the selectivity of the magnetoelastic sensor to a given compound in a mixture that may contain numerous different solute and solvent molecules.