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

这项建议寻求支持的发展和应用的一个新的远程查询传感器技术的基础上的变化的谐振频率的独立磁致弹性厚膜。 这项工作建立在共同研究者积极参与的化学传感器研究的基础上，补充并帮助扩展了化学传感器研究。磁弹性传感器由磁致伸缩、磁弹性非晶金属玻璃的带状厚膜组成[1]。 响应于交流磁场，传感器有效地将磁能转化为弹性能，弹性能又用于使传感器机械变形。 这种机械变形表现出机械谐振，其频率与传感器的长度成反比。 最近已经证明[2]，磁致弹性传感器的谐振频率响应于几个不同的环境参数而变化，包括压力、温度、粘度、界面分子键，并且非常重要的是，当与质量变化的化学响应层[3]结合使用时，化学分析物浓度。 已经使用葡萄糖响应聚合物证明了磁致弹性传感器在远程查询化学感测中的应用[4]。 磁致弹性传感器的谐振频率的变化已被测量响应于低于0.9纳克/毫米2的表面质量负载差。 本研究选择了三种类型的微孔薄膜，提供了广泛的表面化学控制的吸附和/或吸收的气体进入微孔。 通过控制孔径以及表面化学，我们可以调整磁致弹性传感器对混合物中给定化合物的选择性，该混合物可能包含许多不同的溶质和溶剂分子。

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.