Ghanbari Rezvan, Safaiee Rosa, Sheikhi Mohammad H, Golshan Mohammad M, Horastani Z Karami
Department of Electrical Engineering, Shiraz Branch , Islamic Azad University , Shiraz , Iran.
ACS Appl Mater Interfaces. 2019 Jun 19;11(24):21795-21806. doi: 10.1021/acsami.9b00625. Epub 2019 Jun 4.
This paper is devoted to an investigation on the methane sensing properties of graphene (G), decorated with silver nanoparticles (AgNPs), under ambient conditions. To do so, we first present an effective modification in the standard manner of decorating graphene by AgNPs. From structural analysis of the product (AgNPs/G), it is concluded that graphene is indeed decorated by AgNPs of a mean size 29.3 nm, free of aggregation, with a uniform distribution. The so-produced material is then used, as a resistivity-based sensor, to examine its response to the presence of methane gas. Our measurements are performed at relatively low temperatures, for various silver-to-graphene mass ratios (SGMRs) and methane concentrations. To account for the effects of humidity, we have made the measurements, at room temperature, for different levels of humidity. Our results demonstrate that an increase in the SGMR enhances the response of AgNPs/G to methane with an optimum value of SGMR ≅ 12%. It is also illustrated that for methane concentrations less than 2000 ppm, the maximal response increases linearly and rapidly, even at room temperature. Moreover, we demonstrate that AgNPs/G is of low limit of detection, highly stable, selective, reversible, repeatable, and sensor-to-sensor reproducible, for methane sensing. The results thus promise a low-cost and simple-to-fabricate methane sensing device.
本文致力于研究在环境条件下，银纳米颗粒（AgNPs）修饰的石墨烯（G）的甲烷传感特性。为此，我们首先以标准方式对用AgNPs修饰石墨烯进行了有效改进。通过对产物（AgNPs/G）的结构分析得出，石墨烯确实被平均尺寸为29.3 nm、无团聚且分布均匀的AgNPs修饰。然后，将所制备的材料用作基于电阻率的传感器，以检测其对甲烷气体存在的响应。我们在相对较低的温度下，针对各种银与石墨烯的质量比（SGMRs）和甲烷浓度进行了测量。为了考虑湿度的影响，我们在室温下针对不同湿度水平进行了测量。我们的结果表明，SGMR的增加会增强AgNPs/G对甲烷的响应，SGMR的最佳值约为12%。还表明，对于浓度低于2000 ppm的甲烷，即使在室温下，最大响应也会线性且迅速增加。此外，我们证明了AgNPs/G对于甲烷传感具有低检测限、高稳定性、选择性、可逆性、可重复性以及传感器间的可再现性。因此，这些结果预示着一种低成本且易于制造的甲烷传感装置。
