Research On Fiber Microcavity Acoustic Sensors Based On Graphene Hybrid Film

As a kind of optical fiber sensing technology,fiber-optic acoustic sensor has the advantages of small size,anti-electromagnetic interference and easy integration with optical system,and has broad application in oil exploration,underwater communication,seismic research and other fields.As a new two-dimensional nanomaterial,graphene and its derivatives graphene oxide(GO)have been widely studied and applied while one of its most promising application is in the field of sensing.In this paper,a fiber-optic FabryPerot(F-P)interferometric acoustic sensor based on the graphene hybrid film material is fabricated.Based on this sensor,a series of research is done,the main contents are as follows:In this paper,based on the excellent properties of the new two-dimensional graphene materials,a graphene-mixed polymethyl methacrylate(PMMA),multilayer graphene,and GO were proposed as acoustic pressure-sensitive film materials,respectively,and an optical fiber F-P acoustic sensor was fabricated.The structure of the acoustic sensor and the process of making the acousic pressure sensitive film are described in detail.To test the performance of the sensor to the acoustic spectrum response,the sensor is connected to the optic acoustic detection system,and a traditional electrical acoustic sensor is used to as reference.Firstly,the paper introduce the research status of the graphene and the fiber-optic FP sensing technology,and their applications in gas monitoring and acoustic sensing are described in detail.Then,we clearly describe the characteristics and preparation methods of graphene and graphene oxide,and the basic principles of the fiber acoustic sensing technology were introduced in detail,which provides the theoretical basis for the fabrication of the fiber F-P acoustic sensor based on the graphene material to as a sound pressure sensitive film.Next,after understanding the principle of diaphragm-type fiber F-P acoustic sensor,we discuss parameter design,material selection of the sensor and the preparation process of the graphene material making into the optical fiber F-P acoustic sensor.Finally,we connect the sensor to the fiber acoustic system,from the aspects of response,signal-to-noise ratio,senstivety and stability,test the performance of the fiber-optic F-P acoustic sensor based on the graphene hybrid film material,and the performance of the fiber-optic acoustic sensor is optimized and improved from the aspects of film thickness and the structure.The experimental results show that the fiber-optic F-P acoustic sensor based on the graphene hybrid film has more excellent acoustic sensitivity than the traditional electrical acoustic sensor,and is more suitable for applications in the field of micro-sound pressure sensing such as strong electromagnetic interference and small space.