Study On The Systhesis And Performance Of 2D Germanium Selenide Based Photochemical Photodetector

Since the advent of graphene in 2004,more and more two-dimensional materials have been discovered and extensively studied.One of the emerging two-dimensional materials,germanium selenide(Ge Se),exhibits excellent light absorption and response capabilities,making it a promising development prospect in the field of photodetection.However,the higher electron-hole recombination rate of Ge Se has become a restrictive factor for further enhancing its photoelectric conversion performance.In this work,the high carrier mobility of graphene is used to construct a heterojunction between graphene and Ge Se to achieve an effective reduction in the photogenerated carrier recombination rate of Ge Se materials.The experimental results show that the photoelectric performance of the composite materials is better than that of pure Ge Se.Significant improvement.On the other hand,traditional photoelectrochemical photodetectors are generally based on a liquid electrolyte solution system,which exhibits disadvantages such as large volume and inconvenience to carry,which greatly limits the wide application of photoelectrochemical photodetectors.Based on the previous work,this paper constructs a Ge Se-based flexible photodetector based on a quasi-solid electrolyte.Compared with the traditional photoelectrochemical photodetector,it has the advantages of small size,light weight,and portability.The specific work of this paper is carried out from the following two aspects:1.The Ge Se nanosheets were successfully peeled off by the liquid phase stripping method,and the Ge Se-RGO composite material was synthesized by the hydrothermal reduction method.The synthesized Ge Se-RGO composite material was used as the active material to prepare the photoelectrode,and the photoelectrochemical photodetector was constructed.Conduct photoelectric performance evaluation.The experimental results show that when the applied voltage is 0.8 V,the photocurrent density value of the composite photoelectrode is 8.45μA/cm~2,which is three times higher than that of the pure Ge Se nanosheet photoelectrode.When the light intensity is90 m W/cm~2,the light responsivity value can reach 116μA/W.When the light intensity is reduced to 60 m W/cm~2,a higher photocurrent density of 6.2μA/cm~2 can still be obtained,indicating that the prepared Ge Se-RGO-based photodetector has strong light detection ability under low light intensity.In addition,after 50 optical switch cycles,the photoresponse performance of the Ge Se-RGO-based photodetector did not decrease significantly,indicating that the composite photoelectrode has good stability.2.Construct a new type of Ge Se-based flexible photodetector by preparing a quasi-solid electrolyte.The flexible conductive indium tin oxide(ITO)is used as the substrate,and the Ge Se-RGO composite material is loaded to form a photoelectrode,thereby making a photoelectrochemical photodetector with excellent flexibility.The test results show that under different light intensity,the photocurrent increases with the increase of the light intensity,while the increase of the photocurrent decreases with the increase of the light intensity.At the same time,the bending stability test results show that the flexible optoelectronic device exhibits different response characteristics as the applied stress changes under different bending angles.After the Ge Se-RGO flexible device was folded and restored repeatedly for 1000 times,its photocurrent density did not significantly attenuate,showing good stability of the device.