Research Of Ultraviolet Sensing System Based On ZnO/Micro-nano Fiber

Ultraviolet detection has broad application prospects in fire warning,missile tracking,ultraviolet communication,astronomical observation,and biological research.Nano-ZnO materials have high exciton binding energy and great potentialities for development in UV detectors.Combining the advantages of anti-electromagnetic interference,high sensitivity,strong stability and easy preparation of optical fibers,a kind of optical ultraviolet fiber system based on ZnO nanorods is proposed in this paper.The controllable preparation and performance analysis of nanometer ZnO materials,the preparation of optical fiber UV sensors and the sensitivity analysis of devices are studied.The working principle of refractive index change of the ZnO induced by ultraviolet light has also been analyzed systematically,simulation of electric field of ZnO parcel micro-nano optical fiber of is carried out by using finite element analyzing software COMSOL.In addition,a detailed theoretical analysis and simulation are employed to discuss the effect of ZnO material properties change on electric field energy distribution,this which contributes to the foundation of the research on ZnO ultraviolet fiber sensing system.From the point of optical properties of nanometer ZnO materials,using one-dimensional ZnO nanorods with high specific surface area and hydrothermal method that study the influence of OH ion concentration on the crystal structure,surface morphology and optical properties of ZnO nanorods,the optimum OH ion concentration for the preparation of ZnO nanorods was determined to be 0.015M.The micro-nano fiber was used to grow ZnO nanorods at this optimum OH ion concentration and finally a kind of UV sensor device was prepared.The UV sensor system of the straight-through optical path was built.The experimental results show that the prepared UV sensor exhibits good sensitivity and wavelength selectivity when the temperature is constant at 25?and the UV power is in the range of 0mWcm^-29.55mWcm^-2.When the wavelength is from 1527nm to1534 nm,the UV radiation is linear with the transmitted light,and the linearity is more than 0.99.The sensitivity of the sensor increases first and then decreases.At a wavelength of 1530 nm,the sensitivity is 7.10?W/mWcm^-2,which is the highest.The sensor has the characteristics of low preparation cost,compact structure and strong anti-electromagnetic interference capability,and can be widely applied in the fields of partial discharge,open flame detection,and solar illumination monitoring.Further,the fiber-loop ring-down UV sensing system were constructed,which has a sensitivity of 37.57ns/mWcm^-22 when the temperature is constant at 25?and the UV radiation is in the range of 3.18mWcm^-29.55mWcm^-2.The sensing system production is simple,avoids the influence of the light source fluctuation on the detection result,and improves the stability and sensitivity of the system.