U-shaped plastic optical fiber functionalized with metal oxides thin film for H 2 S gas sensor applications

In the current study, a new generation of Hydrogen Sulphide (H 2 S) gas sensor is developed with the aid of Refractive Index (RI) and Evanescent Field (EF) principles dominant in Plastic Optical Fiber (POF) technology. A U-bent POF is functionalized receiving a Pulsed Laser Deposited (PLD) thin film of sensitive transition metal oxide such as CuO, SnO2 and NiO. The U-bent POF containing metal oxide thin film is coupled to an electro-optical set configured to retrieve signals depending on internal RI and EF. The CuO thin film containing sensor developed in present work is capable of sensing H 2 S in room temperature in concentration orders of ppm. It also proved that there is an optimum film thickness to gain higher sensitivity.