Optical gas sensor based on LSPR using ZnO nanoparticles and AAO nanostructure

In this study, we proposed optical gas sensor based on anodized aluminum oxide (AAO) using ZnO nanoparticles. A thin layer of Ni, Au deposited AAO structure was used as substrate, and ZnO nanoparticle layer that was used by sensing membrane was formed by spin coating on the AAO chip. A Ni, Au layer was fabricated to enhance the localized surface plasmon resonance (LSPR) phenomena and ZnO layer was deposited as gas reaction layer. The ZnO nanoparticles have reactivity with Ethanol gas, this reaction make the surface refractive index changes that can be detected by reflected wavelength shift measurements. We collected and plotted peak point of this reflected wave according to ethanol gas concentration. By analyzing this results, we verified that proposed sensor can detect ethanol gas to 5 ppb.