College of Physics, Optoelectronics and Energy, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, People's Republic of China.
Key Laboratory for Thin Film and Micro fabrication of the Ministry of Education, Department of Microelectronics and Nanoscience, School of electronic information and electrical engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Nanoscale Res Lett. 2014 May 21;9(1):251. doi: 10.1186/1556-276X-9-251. eCollection 2014.
We present a useful ammonia gas sensor based on chemically reduced graphene oxide (rGO) sheets by self-assembly technique to create conductive networks between parallel Au electrodes. Negative graphene oxide (GO) sheets with large sizes (>10 μm) can be easily electrostatically attracted onto positive Au electrodes modified with cysteamine hydrochloride in aqueous solution. The assembled GO sheets on Au electrodes can be directly reduced into rGO sheets by hydrazine or pyrrole vapor and consequently provide the sensing devices based on self-assembled rGO sheets. Preliminary results, which have been presented on the detection of ammonia (NH3) gas using this facile and scalable fabrication method for practical devices, suggest that pyrrole-vapor-reduced rGO exhibits much better (more than 2.7 times with the concentration of NH3 at 50 ppm) response to NH3 than that of rGO reduced from hydrazine vapor. Furthermore, this novel gas sensor based on rGO reduced from pyrrole shows excellent responsive repeatability to NH3. Overall, the facile electrostatic self-assembly technique in aqueous solution facilitates device fabrication, the resultant self-assembled rGO-based sensing devices, with miniature, low-cost portable characteristics and outstanding sensing performances, which can ensure potential application in gas sensing fields.
我们提出了一种基于化学还原氧化石墨烯（rGO）片的有用的氨气传感器，通过自组装技术在平行的 Au 电极之间创建导电网络。具有较大尺寸（> 10μm）的负氧化石墨烯（GO）片可以容易地通过静电吸引到带有盐酸半胱氨酸的 Au 电极上。在 Au 电极上组装的 GO 片可以通过水合肼或吡咯蒸气直接还原成 rGO 片，从而提供基于自组装 rGO 片的传感装置。初步结果表明，使用这种简单且可扩展的制造方法用于实际器件的氨气（NH3）气体检测，吡咯蒸气还原的 rGO 对 NH3 的响应（在 50ppm 的 NH3 浓度下比水合肼还原的 rGO 高 2.7 倍以上）要好得多。此外，这种基于吡咯还原的 rGO 的新型气体传感器对 NH3 表现出出色的响应可重复性。总的来说，水溶液中的简单静电自组装技术便于器件制造，所得的基于自组装 rGO 的传感装置具有微型化、低成本、便携性和出色的传感性能，这确保了其在气体传感领域的潜在应用。
