Investigation On The Synthesis And Flexible UV Photodetection Properties Of Metal Nanowires/Zinc Oxide Composites

Recently,flexible and transparent electronic devices for wearble technology have received a great deal of attention.Especially,flexible and transparent UV photodetector,playing important roles in optoelectronic systems,have been extensively studied for the application of pollution monitoring,flare detection,water purification and optical communications.Among the various materials for UV photodetector,ZnO is considered to be a promising functional material,because of its wide direct band gap(3.37 e V)and high exciton binding energy(60 me V),as well as low-cost manufacturing and environmentally friendly.A variety of ZnO materials such as films,nanoparticles nanospheres,nanowires and nanobelts have been used as active materials for UV photodetectors.Within these ZnO structures,one-dimensional ZnO nanowires( NWs)has been regarded as a ideal material for flexible and transparent UV photodetectors,duo to their high responsivities and fast recovery times,high transparency and flexibility.Howerver,it is still a challenge to prepare high-quality and low-cost ZnO NWs for high performance,flexible and transparent UV photodetectors.In this paper,we preapared arrayed and branced ZnO NWs on metal nanowires including silver nanowires(Ag NWs)and copper nanowires(Cu NWs)to obtain metal nanowires/ZnO composites for flexible and transparent UV photodetector.The siginificant resuls achived in this work are list as follows:(1)Arrayed and branced ZnO NWs are successfully grown on Ag NWs via a seed-supported hydrothermal method for fabricating flexible and transparent UV photodetector using Ag NWs as electrodes.The fabricated devices show good UV photodetection properties,high flexibility and transmittance.With a low operation voltage of 0.1 V,the devices based on ZnO NWs arrays have a small rise and decay time of 16 s and 9s,respectively,and a high transmittance of 71%.Moreover,the device maintain good UV detection performance after 1000 times bending cycle.The devices based on branced ZnO NWs have a small rise and decay time of 12 s and 10 s,respectively,and a high transmittance of 65%.(2)Flexible and transparent UV photodetectors based on CuO/ZnO and CuI /ZnO p-n junction are fabricated and investigated.CuO NWs and CuI film are obtaind by the oxidation and iodization of Cu NWs,respectively.Branced ZnO NWs are then grown on CuO NWs and CuI film for obtaining the corresponding CuO/ZnO and CuI /ZnO p-n junction.The fabricated devices based on CuO/ZnO and CuI/ZnO p-n junction exhabite excellent UV sensing performance and high transmittance.For CuO/ZnO p-n junction based UV photodetectors,the ratio of on to off current,Ion/Ioff,is 1075 while the rise and decay times are were 7 s and 5 s,respectively,and the transmittance is 66.7 %.For CuI/ZnO p-n junction based UV photodetectors,values for Ion/Ioff of 189,rise time of 13 s,decay time of 3 s and transmittance of 74.8% are obtained.