Preparation Of Copper Sulfide 3-D Nanostructured Films By Anodization And Their Field Emission Properties

Copper sulfide?Cu_xS,x=1,2?,with a narrow band gap?1.1–2.74 eV?can not only meet the field emitter high electrical conductivity requirements for efficient electronic transport,but also fit its lower work function need?Cu₂S?=5.3 eV,CuS?=4.95 eV?,compared with other metal oxide semiconductor field emitters such as ZnO??=5.3 eV?,Fe₂O₃??=5.6 eV?and CuO??=5.2 eV?.The FE performance is highly affected by the morphology.So it is very important for field emission?FE?characteristics to optimize the morphology of field emitter.Based on the review and analysis of the previous work and the fundamental theory of field electron emission,the subject titled of"Preparation of copper sulfide 3-D nanostructured films by anodization and their field emission properties"systematically summarizes research works of the author during the period of study for a master's degree.In this study,the copper sulfide three-dimensional?3-D?nanostructure films have been designed and prepared by anodization method.The effects of anodization time and current on the morphological structure and field emission performance were studied.Mainly related to the following two aspects of the research content and results:1.The regulation of the morphology evolution of copper sulfide three-dimensional nanoplates array films was explored by setting different anodization times.The three-dimensional?3-D?nanoplates with sharp edges were successfully prepared by one-step anodization method.By abjusting the anodization time to an appropriate time,the value of turn-on field can be dramatically reduced from 11.84 to 2.84 V/?m and the field enhancement factor up to 19899.According to the analysis,the nanoplates prepared with an appropriate time have sharp edges,uniform distribution,and appropriate distribution of emission sites.The excellent field emission characteristics depends on the sharp emission sites which form a strong local field and made the electron to escape into vacuum under a low electric field strength.2.The copper sulfide three-dimensional?3-D?nanosheets/nanobelts were prepared by one-step anodization method.The growth of copper sulfide 3-D nanosheets/nanobelts and the field emission?FE?characteristics have a significantly change with anodization current.The value of turn-on field can be dramatically reduced from 9.77 to 2.80 V/?m.Compared to the three-dimensional nanosheet structure,the emission sites of the three-dimensional nanoplates/nanobelts are more dens e and l es s affect ed b y t he com pensat ed shi el ding effect.In this study,the copper sulfide 3-D nanostructure films showed a long-term thermal stability and better conductivity.Preliminary researches indicate that as a promising field emitter,the copper sulfide 3-D nanostructure films have potential applications in the field of vacuum micro-or nano-electronic devices.