Photochemical deposition fabricated highly sensitive localized surface plasmon resonance based optical fiber sensor

Though the localized surface plasmon resonance (LSPR) based optical fiber sensors have high sensitivity and miniature configurations, most of them suffer from complicated operations and expensive cost in fabrications. To overcome the shortcomings, here we propose a low-cost and simple photochemical method for preparing fiber LSPR sensors by depositing silver nanoparticles on the fiber end face from the reaction solution containing silver nitrate as a metal salt and sodium citrate as a reducing agent. The measurements of sucrose solutions indicate that the proposed sensor can reach the high sensitivity up to ∼400 nm/RIU with satisfied repeatability and reusability. Considering its simple fabrication, high sensitivity and good repeatability, it is believed the proposed sensor can be widely used in various applications such as rapid detection and in-field measurement.