Department d'Enginyeria Electronica, Universitat Rovira I Virgili, Avenida Paisos Catalans 26, 43007Tarragona, Spain.
Laboratoire de Physique du Solide (LPS), Namur Institute of Structured Matter (NISM), University of Namur, Rue de Bruxelles, 61, 500Namur, Belgium.
ACS Appl Mater Interfaces. 2022 Dec 14;14(49):54946-54960. doi: 10.1021/acsami.2c16299. Epub 2022 Dec 5.
Herein, we present, for the first time, a chemoresistive-type gas sensor composed of two-dimensional WSe, fabricated by a simple selenization of tungsten trioxide (WO) nanowires at atmospheric pressure. The morphological, structural, and chemical composition investigation shows the growth of vertically oriented three-dimensional (3D) assemblies of edge-enriched WSe nanoplatelets arrayed in a nanoflower shape. The gas sensing properties of flowered nanoplatelets (2H-WSe) are investigated thoroughly toward specific gases (NH and NO) at different operating temperatures. The integration of 3D WSe with unique structural arrangements resulted in exceptional gas sensing characteristics with dual selectivity toward NH and NO gases. Selectivity can be tuned by selecting its operating temperature (150 °C for NH and 100 °C for NO). For instance, the sensor has shown stable and reproducible responses (24.5%) toward 40 ppm NH vapor detection with an experimental LoD < 2 ppm at moderate temperatures. The gas detecting capabilities for CO, H, CH, and NO were also investigated to better comprehend the selectivity of the nanoflower sensor. Sensors showed repeatable responses with high sensitivity to NO molecules at a substantially lower operating temperature (100 °C) (even at room temperature) and LoD < 0.1 ppm. However, the gas sensing properties reveal high selectivity toward NH gas at moderate operating temperatures. Moreover, the sensor demonstrated high resilience against ambient humidity (Rh = 50%), demonstrating its remarkable stability toward NH gas detection. Considering the detection of NO in a humid ambient atmosphere, there was a modest increase in the sensor response (5.5%). Furthermore, four-month long-term stability assessments were also taken toward NH gas detection, and sensors showed excellent response stability. Therefore, this study highlights the practical application of the 2H variant of WSe nanoflower gas sensors for NH vapor detection.
本文首次提出了一种由三氧化钨（WO）纳米线在常压下简单硒化制备的二维 WSe2 电阻式气体传感器。形态、结构和化学成分研究表明，垂直定向的三维（3D）组装体生长，由边缘富集的 WSe2 纳米板排列成纳米花形状。对花状纳米板（2H-WSe）在不同工作温度下对特定气体（NH3 和 NO）的气体传感性能进行了深入研究。3D WSe2 与独特的结构排列相结合，对 NH3 和 NO 气体表现出了卓越的气敏特性，具有双重选择性。选择性可以通过选择工作温度（150°C 用于 NH3，100°C 用于 NO）来调节。例如，该传感器在中等温度下对 40ppm NH3 蒸气检测表现出稳定且可重复的响应（24.5%），实验 LoD<2ppm。还研究了传感器对 CO、H2、CH4 和 NO 的气体检测能力，以更好地理解纳米花传感器的选择性。传感器对 NO 分子表现出可重复的响应，在较低的工作温度（100°C）（甚至在室温下）下具有高灵敏度，LoD<0.1ppm。然而，在中等工作温度下，气体传感性能对 NH3 气体表现出高选择性。此外，传感器对环境湿度（Rh=50%）表现出高弹性，对 NH3 气体检测表现出显著的稳定性。考虑到在潮湿环境气氛中检测 NO，传感器的响应略有增加（5.5%）。此外，还对 NH3 气体检测进行了长达四个月的长期稳定性评估，传感器表现出出色的响应稳定性。因此，本研究强调了 2H 变体 WSe2 纳米花气体传感器在 NH3 蒸气检测方面的实际应用。
