In this work, we, for the first time, propose a quartz crystal microbalance (QCM) humidity sensor that is prepared by a one-step method based on pencil drawing. The scanning electron microscopy (SEM), atomic force microscope (AFM), and Raman spectra confirm some graphite flakes, and a layer of sensing film is formed, demonstrating the successful preparation of the QCM sensor. A series of experiments were performed by means of oscillating circuit and impedance analysis at room temperature. The impedance analysis method demonstrates that the QCM humidity sensor exhibits an excellent stability with a quality factor ( Q{Q} ) that only drops from 47 923 to 43 849 in the whole humidity range, which is better than ever reported QCM humidity sensors. In addition, the sensor shows a good long-term stability with a maximal frequency deviation of less than 5% in a long-term test. Furthermore, the sensor displays a rapid response time ~8s and a recovery time less than 5 s. The underlying reasons for these excellent properties of the proposed sensor are analyzed and discussed. This research demonstrates that the pencil-drawn method is a simple, green, and cost-effective way for constructing a QCM humidity sensor with high performance.

中文翻译：

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基于铅笔绘制法的高品质因数石英晶体微天平（QCM）湿度传感器


在这项工作中，我们首次提出了一种基于铅笔绘图的一步法制备的石英晶体微天平（QCM）湿度传感器。扫描电子显微镜（SEM）、原子力显微镜（AFM）和拉曼光谱证实了一些石墨片，并形成了一层传感膜，证明了QCM传感器的成功制备。通过振荡电路和室温阻抗分析进行了一系列实验。阻抗分析方法表明，QCM湿度传感器表现出优异的稳定性，品质因数（Q{Q}）在整个湿度范围内仅从47 923下降到43 849，优于以往报道的QCM湿度传感器。此外，该传感器表现出良好的长期稳定性，在长期测试中最大频率偏差小于5%。此外，该传感器的快速响应时间约为 8 秒，恢复时间小于 5 秒。分析和讨论了所提出的传感器具有这些优异性能的根本原因。这项研究表明，铅笔绘制方法是构建高性能 QCM 湿度传感器的一种简单、绿色且经济高效的方法。