Silver Nanowire-Induced Sensitivity Enhancement of Optical Oxygen Sensors Based on AgNWs–Palladium Octaethylporphine–Poly(methyl methacrylate) Microfiber Mats Prepared by Electrospinning

Sensitivity enhancement of optical oxygen sensors is crucial for the characterization of nearly anoxic systems and oxygen quantification in trace amounts. In this work, for the first time we presented the introduction of silver nanowires (AgNWs) as a sensitivity booster for optical oxygen sensors based on AgNWs-palladium octaethylporphine-poly(methyl methacrylate) (AgNWs@PdOEP-PMMA) microfiber mats prepared by electrospinning. Herein, a series of sensing microfiber mats with different loading ratios of high aspect ratio AgNWs were fabricated, and the corresponding sensitivity enhancement was systematically investigated. With increasing incorporated ratios, the AgNWs@PdOEP-PMMA-sensing microfiber mats exhibited a swift response (approx. 1.8 s) and a dramatic sensitivity enhancement (by 243% for the range of oxygen concentration 0-10% and 235% for the range of oxygen concentration 0-100%) when compared to the pure PdOEP-PMMA microfiber mat. Additionally, the as-prepared sensing films were experimentally confirmed to be highly photostable and reproducible. The advantages of AgNW-induced sensitivity enhancement could be useful for the rational design and realization of revolutionary highly sensitive sensors and expected to be readily applicable to many other high-performance gas sensor devices.