Rani Sanju, Kumar Manoj, Garg Parveen, Parmar Rahul, Kumar Ashish, Singh Yogesh, Baloria Vishal, Deshpande Uday, Singh Vidya Nand
CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, Uttar Pradesh, India.
ACS Appl Mater Interfaces. 2022 Apr 6;14(13):15381-15390. doi: 10.1021/acsami.1c24679. Epub 2022 Mar 28.
Many toxic gases are mixed into the atmosphere because of increased air pollution. An efficient gas sensor is required to detect these poisonous gases with its ultrasensitive ability. We employed the thermal evaporation method to deposit an n-SnSe/p-SnO/n-SnSe heterojunction and observed a temperature-dependent n-p-n switching NO gas sensor with high selectivity working at room temperature (RT). The structural and morphological properties of the material were studied using the characterization techniques such as XRD, SEM, Raman spectroscopy, XPS, and HRTEM, respectively. At RT, the device response was 256% for 5 ppm NO. The response/recovery times were 34 s/272 s, respectively. The calculated limit of detection (LOD) was ∼115 ppb with a 38% response. The device response was better with NO gas than with SO, NO, HS, CO, H, and NH. The mechanism of temperature-dependent n-p-n switching, fast response, recovery, and selective detection of NO at RT has been discussed on the basis of physisorption and charge transfer. Thus, this work will add a new dimension to 2D materials as selective gas detectors at room temperature.
由于空气污染加剧，许多有毒气体混入大气中。需要一种高效的气体传感器来凭借其超灵敏能力检测这些有毒气体。我们采用热蒸发法沉积了一种n-SnSe/p-SnO/n-SnSe异质结，并观察到一种在室温（RT）下工作的具有高选择性的温度依赖性n-p-n开关型NO气体传感器。分别使用XRD、SEM、拉曼光谱、XPS和HRTEM等表征技术研究了该材料的结构和形态特性。在室温下，该器件对5 ppm NO的响应为256%。响应/恢复时间分别为34 s/272 s。计算得出的检测限（LOD）约为115 ppb，响应为38%。该器件对NO气体的响应比对SO、NO、HS、CO、H和NH的响应更好。基于物理吸附和电荷转移，讨论了温度依赖性n-p-n开关、快速响应、恢复以及在室温下对NO进行选择性检测的机制。因此，这项工作将为二维材料作为室温下的选择性气体探测器增添新的维度。
