Al-Hamry Ammar, Pan Yang, Rahaman Mahfujur, Selyshchev Oleksandr, Tegenkamp Christoph, Zahn Dietrich R T, Pašti Igor A, Kanoun Olfa
Measurement and Sensor Technology, Chemnitz University of Technology, Reichenhainer Str. 70, 09126 Chemnitz, Germany.
Semiconductor Physics, Chemnitz University of Technology, Reichenhainer Str. 70, 09126 Chemnitz, Germany.
ACS Appl Electron Mater. 2024 May 31;6(6):4718-4734. doi: 10.1021/acsaelm.4c00729. eCollection 2024 Jun 25.
Flexible temperature sensors are becoming increasingly important these days. In this work, we explore graphene oxide (GO)/poly(vinyl alcohol) (PVA) nanocomposites for potential application in temperature sensors. The influence of the mixing ratio of both materials, the reduction temperature, and passivation on the sensing performance has been investigated. Various spectroscopic techniques revealed the composite structure and atomic composition. These were complemented by semiempirical quantum chemical calculations to investigate rGO and PVA interaction. Scanning electron and atomic force microscopy measurements were carried out to evaluate dispersion and coated film quality. The temperature sensitivity has been evaluated for several composite materials with different compositions in the range from 10 to 80 °C. The results show that a linear temperature behavior can be realized based on rGO/PVA composites with temperature coefficients of resistance (TCR) larger than 1.8% K and a fast response time of 0.3 s with minimal hysteresis. Furthermore, humidity influence has been investigated in the range from 10% to 80%, and a minor effect is shown. Therefore, we can conclude that rGO/PVA composites have a high potential for excellent passivation-free, humidity-independent, sensitive, and fast response temperature sensors for various applications. The GO reduction is tunable, and PVA improves the rGO/PVA sensor performance by increasing the tunneling effect and band gap energy, consequently improving temperature sensitivity. Additionally, PVA exhibits minimal water absorption, reducing the humidity sensitivity. rGO/PVA maintains its temperature sensitivity during and after several mechanical deformations.
如今，柔性温度传感器正变得越来越重要。在这项工作中，我们探索了氧化石墨烯（GO）/聚乙烯醇（PVA）纳米复合材料在温度传感器中的潜在应用。研究了两种材料的混合比例、还原温度和钝化对传感性能的影响。各种光谱技术揭示了复合材料的结构和原子组成。通过半经验量子化学计算对这些进行补充，以研究还原氧化石墨烯（rGO）和PVA的相互作用。进行了扫描电子显微镜和原子力显微镜测量，以评估分散性和涂膜质量。对几种不同组成的复合材料在10至80°C范围内的温度敏感性进行了评估。结果表明，基于rGO/PVA复合材料可以实现线性温度行为，其电阻温度系数（TCR）大于1.8%/K，响应时间快至0.3 s，滞后极小。此外，还研究了10%至80%范围内的湿度影响，结果显示影响较小。因此，我们可以得出结论，rGO/PVA复合材料在用于各种应用的无钝化、与湿度无关、灵敏且响应快速的优秀温度传感器方面具有很高的潜力。GO的还原是可调的，PVA通过增加隧穿效应和带隙能量来提高rGO/PVA传感器的性能，从而提高温度敏感性。此外，PVA的吸水率极低，降低了湿度敏感性。rGO/PVA在几次机械变形过程中和之后都能保持其温度敏感性。
