A simple and cost-effective fabrication of CO2 sensor via electrospinning polyether sulfone nanofibers toward ultra-high detection sensitivity

Accurate detection of carbon dioxide (CO₂) is of great significance to environmental protection. In this study, a simple, highly sensitive, and linearity CO₂ sensors is successfully proposed. Furthermore, for the first time, the sensor was demonstrated by electrospinning a layer of polyether sulfone (PES) nanofiber film wrapped onto a micro-tapered long period fiber grating (MT-LPFG). Given that CO₂ molecules effortlessly permeate the mesh pores of the electrospun PES films, modulations in both the refractive index (RI) and volume of PES films can be induced, consequently leading to alterations in the resonant wavelength of the grating. The experimental results demonstrate the exceptional performance of the MT-LPFG sensor utilizing PES films, showcasing a significant response within a range of (1.99 %-10 %). This sensor exhibits a sensitivity of 0.068 nm/%, linearity of 0.994, and an impressively low CO₂ detection limit of 1.2 %. Moreover, the sensor exhibits exceptional recovery properties and demonstrates clear differentiation between nitrogen (N₂) and CO₂. This cost-effective sensor holds significant economic value and holds promise for widespread application in industrial processes and commercialization.