Fiber optic humidity sensing with few layers molybdenum disulfide

Because of high surface-to-volume ratio, few layers MoS2 material as a kind of 2D materials has been attracted more attention nowadays to be used for photonics devices. We investigated the performance of few-layer MoS2 when it is covered on a side polished fiber (SPF) to sense relative humidity (RH) of environments. The SPF was made by wheel side polishing method. The few layers MoS2 was deposited on the side polished surface to be a sensing material. As the environmental humidity changes, the output optical power of the all fiber sensor will change due to the interaction between evanescent field of fiber and MoS2 material. The change of output power of fiber sensor can reach 16.67dB in the relative humidity range of 40-85%. Experiments using the fiber sensor on human breathing have been made and the respondence has achieved. The experiments showed that the fiber sensor can be used in medical instruments. Key words: fiber sensor, side-polished fiber, humidity sensing, 2D material, MoS2.