Wong Timothy S B, Newman Roger C
Department of Chemical Engineering and Applied Chemistry, University of Toronto 200 College Street Toronto ON M5S 3E5 Canada
Nanoscale Adv. 2020 Jan 8;2(2):777-784. doi: 10.1039/d0na00010h. eCollection 2020 Feb 18.
Volatile organic compounds (VOC) are ubiquitous in industrial applications creating a pressing desire for novel transduction pathways to build a broad family of new gas sensors. Nanoporous gold (NPG) is a material with a vast range of untapped potential applications; offering a high surface area found generally in nanomaterials, while also being comparatively simple to fabricate. NPG based sensors can also leverage the unique physics of gold at the nanoscale. In this work, we leverage the multiple unique nanoscale phenomena associated with NPG to demonstrate two novel transduction mechanisms to sense humidity, a model compound. Through direct electrical measurements of NPG, we were able to sense changes in the electronic properties of NPG induced by ambient humidity. We propose two novel transduction mechanisms: chemoresistive changes induced by surface adsorption and electrochemical capacitive changes induced by the electric double layer to detect humidity. To our knowledge this is the first reported application of both these mechanisms for sensing any volatile compounds utilizing NPG.
挥发性有机化合物（VOC）在工业应用中无处不在，这使得人们迫切需要新颖的传感途径来构建一系列新型气体传感器。纳米多孔金（NPG）是一种具有广泛潜在应用的材料；它具有纳米材料中常见的高比表面积，同时制造相对简单。基于NPG的传感器还可以利用纳米尺度下金的独特物理性质。在这项工作中，我们利用与NPG相关的多种独特纳米尺度现象，展示了两种用于检测作为模型化合物的湿度的新型传感机制。通过对NPG的直接电学测量，我们能够检测到环境湿度引起的NPG电子性质的变化。我们提出了两种新型传感机制：表面吸附引起的化学电阻变化和双电层引起的电化学电容变化来检测湿度。据我们所知，这是首次报道利用NPG通过这两种机制检测任何挥发性化合物的应用。
