Tapered Fiber Based on Cs-Pva Coating for Cu2+ Detection

With the rapid development of industry, the speedy and stable detection of Cu2+ is of great significance to the environment and human health. This paper designs a fiber sensor that is simple to make, highly sensitive, and specifically used for Cu2+ detection. Chitosan and polyvinyl alcohol are mixed and coated on the waist-cone region of a tapered optical fiber using the dip coating method, preparing three types of fiber sensors: uncoated, coated with CS-PVA film, and coated with CS-PVA ion-imprinted film. The experimental results show that in the concentration range of 0-100 μmol/L Cu2+, the sensitivity of coated CS-PVA film tapered fiber sensor can reach 85.1316 pm·μmol-1·L, the LOD is 0.388 μM, and the linearity can reach 0.98076. The improved CS-PVA ion imprinted fiber sensor has specific detection function for Cu2+. The sensor fabrication is simple, operation is convenient, and it exhibits high sensitivity in detecting Cu2+. It offers specific detection of Cu2+ ions. By altering the template ions in the ion imprinting process, it can detect other heavy metal ions, thus showing potential in heavy metal detection.