Research Initiation Awards: In-Situ Measurement of Interfacial Mass Changes with Chemically Milled At-cut Quartz Crystals

压电换能器因其检测微小界面质量变化的能力而被利用。石英晶体微天平（QCM），由at切割的石英薄片夹在两个金属激发电极之间，已广泛应用于这方面。QCM的格式特别有吸引力，因为at切割的石英晶体价格低廉，易于处理，并且可以配置，以便其中一个激励电极可以用作传统电化学电池中的工作电极。然而，由于工作频率较低（0.10），与其他换能器相比，QCM的应用受到了一定的限制MHz)的QCM。该计划旨在通过研究在蒸汽和液体介质中使用高频（高达100 MHz），微型化学研磨at切割石英晶体进行质量检测来消除这一障碍。该项目的目标是证明(1)这些晶体对金属沉积和气态分析物吸附成活性薄膜的质量敏感性；(2)这些装置在液体介质中的生存能力和质量敏感性；(3)检测电化学诱导的质量变化。(4)使用这些谐振器的各种传感器配置的可行性和(5)使用这些晶体作为粘度传感器。

Piezoelectric transducers have been exploited for their ability to detect minute interfacial mass changes. The quartz crystal microbalance (QCM), comprising a thin wafer of AT-cut quartz sandwiched between two metallic excitation electrodes, has been used extensively in this regard. The format of the QCM is particularly attractive since AT-cut quartz crystals are inexpensive, easily handled and can be configured so that one of the excitation electrodes can be used as a working electrode in a conventional electrochemical cell. Applications of the QCM have been somewhat limited, however, by low sensitivity compared to other transducers because of the rather low operating frequencies (.10 MHz) of the QCM. This program aims to remove this obstacle by investigating the use of high frequency (up to 100 MHz), miniature chemically milled AT-cut quartz crystals in mass detection, both in vapor and liquid media. The goals this project will be to demonstrate (1) the mass sensitivity of these crystals to metal deposition and adsorption of gaseous analytes into thin active films, (2) the viability and mass sensitivity of these devices in liquid media (3) detection of electrochemically induced mass changes, (4) the feasibility of various sensor configurations using these resonators and (5) the use of these crystals as viscosity sensors.