Low-dimensional ZnO Nanomaterials Synthesis And Device Research

As ZnO nanomaterials have many advantages of the photoelectric, together with itspreparation methods, they get varied potential applications in the field of surface acousticwave devices, pressure-sensitive gas sensors, solar cells, and light-emitting diode. In thispaper, the most widely used two types of materials, ZnO nanoparticles/ZnO nanowires, arestudied in the way of synthesis analysis, and device applications. Mainly includes:（1） Three different morphologies of ZnO nanoparticles have been synthesized byhydrothermal and made into UV detector on PDMS flexible substrates by a simple film.According to the performance of device and also ZnO UV response mechanism, we selectedreduced graphene oxide （RGO） as modified material to decorate ZnO. Through the study ofdifferent quality percentages of the RGO in ZnO composite, we found that RGO certainchemical bonds formed with ZnO composite process can quickly lead away ZnO light tostimulate the formation of charge. The ultraviolet detector made from0.05%RGO/ZnOcomposite shows the best performance.（2） Two-step CVD method synthesis of ZnO/ZnS_xSe_1-xcore/shell nanowire arrays havebeen used as photoanode materials. Through the PEC testing we found that the lightresponse of the core/shell structure has been greatly enhanced especially the visible lightresponse.And then we synthesized ZnO/ZnS_xSe_1-x/ZnSe double-shell nanostructures using athree-step CVD method to get further enhancement. And this kind material also has beenstudied its PEC to observe further enhancement of the light response as a photoelectric pole.The photoluminescence （PL） spectrum shows its optical properties. In particular, a detailedstudy has been carried out on about the behavior of the interface between each layer.We found that the core-shell structure can effectively improve the absorption of lightresponse of the material, mainly due to the Type II Construction of the belt structure, whichimproves the separation efficiency of the material system, the electron-hole. PL spectra explains from the spectral angle the reason why the core-shell nanowire arrays have so highefficiency of electron-hole separation.