【作者】 盛睿；

【导师】 康琪；

【作者基本信息】 山东师范大学 ， 分析化学， 2012， 硕士

【摘要】 石英晶体微天平(QCM)是一种对质量变化高度敏感的化学传感器，具有灵敏度高，无需标记处理、可原位，实时监测界面过程的优点，在界面传质过程研究中获得了广泛的应用。本论文先介绍了近年来QCM的发展概况，开展了以下研究工作。1、液隔电极式压电传感器实时监测石英表面化学镀Ni-P本章用液隔电极压电传感器(ESPS)监测了在石英表面化学镀Ni-P层的相关动力学过程。在除油和粗化过程的质量变化分别遵循指数衰减和线性下降模式。随着HF+H2SiF6浓度增加和溶液温度升高，石英腐蚀速率增加。非离子型表面活性剂OP的存在可降低腐蚀速率。初始的Ni-P层化学镀过程包含四个阶段:诱导期，加速期，减速期和稳定期。升高溶液温度使沉积速率增大。在所用的实验条件下，在40和48°C，沉积速率分别是26.7和45.3nm/min。Ni-P层在1mol/L的HCl溶液中，在最初的10分钟溶解速率随着接触时间延长而降低，然后稳定在0.12nm/min的水平，Ni-P层在Al2O3抛光粉中的磨损速率比在1mol/L的HCl溶液中的溶解速率大，而且随时间变化不大。ESPS技术是原位监测石英材料上化学镀过程质量变化的有效工具。2、非均匀膜层的压电传感检测方法与冰膜吸附研究本章将QCM用于冰膜吸附的研究中，实验过程中发现在QCM表面制备冰膜后常出现峰分裂的现象，采用峰高加权平均算法，用以测定峰分裂条件下QCM的表面质量变化，观察了冰膜在低温条件下升华过程。通过条件优化，在QCM表面制备成均匀、刚性的薄冰膜层，避免谐振峰的分裂，降低冰膜的升华速率，研究了冰膜与乙醇、HCl和NH3三种气体作用过程中冰膜的质量变化和粘度变化，讨论了冰膜厚度、吸附物浓度的影响。在乙醇吸附体系中，冰膜融化，频率变化来自相变过程，在HCl吸附体系中，频率变化来自表面吸附与膜粘度变化，在NH3吸附体系中，冰膜保持刚性，频率变化来自表面吸附，用阻抗分析法可以区分与校正冰膜升华与非质量效应的影响，为拓展QCM的低温区的应用进行了有益的探索。3、超声波对石英晶体微天平响应性能的影响本章以阻抗分析法研究了超声波对石英晶体微天平(QCM)响应特性的影响，结果表明，在超声波存在时QCM的纵波传播与反射受到干扰，QCM的阻抗-频率曲线上出现很多的毛刺干扰波，使QCM的信噪比下降。当采取消除纵波干扰的措施后，毛刺干扰波消失，实验测试了QCM的谐振频率及动态电阻对表面质量负载变化及液体粘度、密度的改变的响应，证实超声波对QCM的厚度剪切模式无影响。QCM应用于监测表面活性剂去除油污膜的过程，结果表明在超声波作用下油污膜的去除速率大幅度提高，在超声波环境下也能使用QCM进行可靠的传感检测。更多还原

【Abstract】 Quartz crystal microbalance (QCM) is a chemical sensors which is highly sensitive tothe mass change onto electrode surface. Compared with other techniques, it provides a uniquemethod for observing in situ events, in which changes can be monitored in real time with highsensitivity, so it has a wide range of applications. This paper first introduces the overview ofthe development about the piezoelectric sensors in recent years. We carried out the followingresearch works.1) Real time monitor electroless plating of Ni-P film on quartz surface by an electrode-separated piezoelectric sensorThe kinetics related to an electroless Ni-P deposition on quartz surface was monitored byan electrode-separated piezoelectric sensor (ESPS). It was shown that the mass changesduring the initial grease removing and quartz coarsening process followed an exponentialdecay and linear decrease models, respectively. The corrosion rate of quartz increased withincreasing concentration of HF+H2SiF6and solution temperature. The presence of non-ionicsurfactant OP blocked the corrosion rate. The initial Ni-P plating process consisted of fourstages: an induction period, an acceleration period, a deceleration period and a stationaryperiod. When the temperature was increased from40to48°C, the average deposition rate wasincreased from26.7to45.3nm/min, respectively. In the corrosion process of the Ni-P film in1mol/L HCl, the dissolving rate decreased with contact time to a stable level of0.12nm/min.The wearing rate of the Ni-P film in Al2O3polishing powder was much larger than thedissolving rate in1mol/L HCl and decreased slightly with time. The ESPS technique is aneffective tool for in-situ monitoring of the mass changes in electroless plating on quartzmaterial.2) Response of quartz crystal microbalance with inhomogeneous film and monitor theadsorption behavior on the ice filmDuring the experiment stage of preparation an ice film on the surface of the QCM toinvestigate the adsorption behavior on the ice film, the splitting of the resonant peak of QCMwas observed if heavy and inhomogeneous film was prepared. We used a peak height weighted average method to get the information about the mass change on the surface underthe situation of peak split. We also studied the factors which affected the sublimation of icefilm at low temperatures. After the optimization of the conditions, homogeneous, rigid icefilm was prepared on the surface of the QCM and the resonance peak splitting was avoided.The sublimation rate of ice film was measured. The changes of mass and viscosity on the icefilm during the interaction with ethanol, HCl and NH3were investigated by QCM. Theinfluence of thickness of the ice film and the concentration of the gases on adsorption wasdiscussed. Ice film was melted after ethanol adsorption. The frequency change was duemainly to phase change of ice. In the HCl adsorption system, the frequency change came fromsurface adsorption and change in film viscosity. In the NH3adsorption system, the ice filmremained rigid, and the frequency change came from surface adsorption. We could distinguishand correct the frequency changes from ice film sublimation and non-mass effect using theimpedance analysis method. The result is helpful to expand the application of the QCM in lowtemperature causes.3) Influence of ultrasonic wave on the response of a quartz crystal microbalance inimpedance analysis methodThe effect of ultrasonic wave on the response of a quartz crystal microbalance (QCM)was investigated by an impedance analysis method. In the presence of ultrasonic wave, thesignal-to-noise of QCM in a liquid phase is reduced as burrs are added on itsimpedance-frequency spectrum. This kind of effect is ascribed to the fact that the reflectioncondition for the longitudinal wave from QCM is disturbed by ultrasonic wave. The burrnoise on the resonant peak of QCM disappears when the longitudinal wave effect iseliminated. The changes in the resonant frequency and motional resistance of QCM weremeasured under different viscosity and density of liquid phase and the surface mass loading. Itis shown that the thickness-shear model of QCM is not influenced by ultrasonic wave effect.The removal of hydrophobic film by non-ionic surfactant were monitored by QCM. Theremoval is greatly speeded under ultrasonic conditions. The result showed that QCM can beused under ultrasonic environment for reliable sensing detection.更多还原