M-Solv Ltd , Oxonian Park, Langford Locks , Kidlington, Oxford OX5 1FP , U.K.
Department of Physics and Astronomy , University of Sussex , Brighton BN1 9RH , U.K.
ACS Appl Mater Interfaces. 2018 Jun 27;10(25):21740-21745. doi: 10.1021/acsami.8b05105. Epub 2018 Jun 12.
Recent advances in the large-scale production of graphene have led to the availability of solution-processable platelets on the commercial scale. Langmuir-Schaefer deposition is a scalable process for forming a percolating film of graphene platelets, which can be used for electronic gas sensing. Here, we demonstrate the use of this deposition method to produce functional gas sensors, using a chemiresistor structure from commercially available graphene dispersions. The sensitivity of the devices and the repeatability of the electrical response upon gas exposure have been characterized. Raman spectroscopy and Kelvin probe force microscopy show doping of the basal plane using ammonia (n-dopant) and acetone (p-dopant). The resistive signal is increased upon exposure to both gases, showing that sensing originates from the change in the contact resistance between nanosheets. We demonstrate that Arrhenius fitting of desorption response potentially allows measurements of desorption process activation energies for gas molecules adsorbed onto the graphene nanosheets.
近年来，石墨烯的大规模生产取得了进展，商业上可提供可溶液加工的石墨烯片。Langmuir-Schaefer 沉积是一种可扩展的方法，可以形成石墨烯片的渗滤膜，可用于电子气体感测。在这里，我们展示了使用这种沉积方法来制备功能气体传感器，使用市售的石墨烯分散体的化学电阻结构。已经对器件的灵敏度和气体暴露时的电响应的重复性进行了表征。拉曼光谱和 Kelvin 探针力显微镜显示使用氨（n-掺杂剂）和丙酮（p-掺杂剂）对基面进行掺杂。暴露于两种气体后，电阻信号增加，表明传感源自纳米片之间接触电阻的变化。我们证明，解吸响应的 Arrhenius 拟合可能允许测量吸附在石墨烯纳米片上的气体分子的解吸过程激活能。
