Sahu Praveen Kumar, Pandey Rajiv K, Dwivedi R, Mishra V N, Prakash R
Department of Electronics Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India.
School of Materials Science and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India.
Sci Rep. 2020 Feb 19;10(1):2981. doi: 10.1038/s41598-020-59726-5.
The higher operating temperature of metal oxide and air instability of organic based NO sensor causes extremely urgent for development of a reliable low cost sensor to detect NO at room temperature. Therefore, we present a fabrication of large area Polymer/GO nano hybrid thin film for polymer thin film transistors (PTFTs) based NO sensors assisted via facile method named 'spreading-solidifying (SS) method', grown over air/liquid interface and successive investigation of effect of NO on film via several characterizations. The PTFTs sensor has demonstrated swift and high response towards low concentration of NO gas with air stability and provided real time non-invasive type NO sensor. Herein, we are reporting the nanohybrid PBTTT/GO composite based PTFT sensor with good repeatability and sensor response for low concentration NO. The thin film grown via SS technique has reported very good adsorption/desorption of target analyte having response/recovery time of 75 s/523 s for 10 ppm concentration of NO gas. It has been observed that % change in drain current (sensor response) saturated with increasing concentration of NO. The transient analysis demonstrates the fast sensor response and recovery time. Furthermore, in order to understand the insight of high performance of sensor, effect of NO on nanohybrid film and sensing mechanism, an in situ investigations was conducted via multiple technique viz. spectral, electronic, structural, and morphological characterization. Finally, the performance of sensor and the site of adsorption of NO at polymer chains were argued using schematic diagram. This work shows the simple fabrication process for mass production, low cost and room temperature operated gas sensors for monitoring the real-time environment conditions and gives an insight about the sensing mechanism adsorption site of NO.
金属氧化物较高的工作温度以及有机基NO传感器的空气不稳定性，使得开发一种可靠的低成本室温NO传感器变得极为迫切。因此，我们介绍了一种大面积聚合物/氧化石墨烯纳米混合薄膜的制备方法，该薄膜用于基于聚合物薄膜晶体管（PTFT）的NO传感器，采用一种名为“铺展-固化（SS）法”的简便方法辅助制备，在气/液界面上生长，并通过多种表征手段对NO对薄膜的影响进行了后续研究。PTFT传感器对低浓度NO气体表现出快速且高的响应，具有空气稳定性，提供了实时非侵入式NO传感器。在此，我们报道了基于纳米混合聚（2,5-二噻吩并[3,2-b:2',3'-d]噻吩）/氧化石墨烯复合材料的PTFT传感器，对低浓度NO具有良好的重复性和传感器响应。通过SS技术生长的薄膜对目标分析物具有非常好的吸附/解吸性能，对于10 ppm浓度的NO气体，响应/恢复时间分别为75 s/523 s。已经观察到，漏极电流的百分比变化（传感器响应）随着NO浓度的增加而饱和。瞬态分析表明传感器响应和恢复时间很快。此外，为了理解传感器高性能的内在原因、NO对纳米混合薄膜的影响以及传感机制，通过多种技术进行了原位研究，即光谱、电子、结构和形态表征。最后，使用示意图对传感器的性能以及NO在聚合物链上的吸附位点进行了论证。这项工作展示了用于大规模生产的简单制造工艺、低成本且室温操作的气体传感器，用于监测实时环境条件，并对NO的传感机制吸附位点提供了深入了解。
