Preparation, Luminescent Properties And Field Emission Properties Reseach On Indium Oxide （In₂O₃） Nanomaterials

Indium oxide (In2O3) nano-materials has become a research hotspots in wide band gapsemiconductor nano-materials, and has a great applied prospect in optoelectronic materials, sensingmaterials, display devices and solar cells because of its good conductivity, high critical breakdownfield, high thermal conductivity, low electron affinity, good chemical stability. In recent years,researchers have made some progress in the preparation and properties of indium oxide (In2O3)nanostructures. People have already prepared a variety of indium oxide nanostructures by lots ofphysical and chemical methods, and have also made the corresponding progress in luminescentproperties and field emission properties of indium oxide nanostructures, but there are still someproblems unclear on preparation, luminescence mechanism and the field emission performance.Therefore, this thesis adopted the most convenient and low-cost CVD method to find out the optimumpreparation for In2O3nanostructures, and investigated the luminescence mechanism and field emissionproperties of indium oxide through the analysis of its microstructure and compositions, whichprovided a certain reference significance for the preparation and properties research of indium oxidenanostructures. The main contents are as follows:The In2O3nanoparticles, nanowires, Fe doping of nanowires were synthesized successfully bychemical vapor deposition method with controlling the technological parameters parameters properly,such as retention time, temperature, flow rate of carrier gas, and Fe doped In2O3nanowires areseldom studied.The morphology and structural of prepared In2O3nanostructures were characterized by scanningelectron microscopy (SEM) and transmission electron microscopy (TEM); the compositions of In2O3nanostructures were analyzed by XRD, EDS, XPS, XAFS.Photoluminescence spectrum analysis indicated that there existed different peak lighted indifferent nanostructures. The PL of the octahedron particles mainly comes from near edge glow, zhereis an UV light emitting peak at384nm; cutting angle of polyhedron has a410peak in addition to384nm peak, and it might has been caused by the surface defects in the process of growth; nanowiresstructure can produce oxygen vacancy, surface defect etc in the process of growth, thus it caused in423nm blue-green emission peak, in the ultraviolet light, and UV-emitting light-emitting region alsohas a peak; Fe-doped In2O3nanowires, because of Fe into the lattice, occupying In1position,produce oxygen vacancy defects and more defects, thus resulting in a more luminous peaks, includingthe UV emission peak394nm, blue and green emission peak404nm,417nm and423nm. Thesephotoluminescence peaks were mainly located in the ultraviolet and blue-green light-emitting zone,which came from the near belt edge glow and shallow level caused by defects respectively.We measured the field emission properties of several preparation nanostructures and investigatedthe effect of morphology, emitter density and doped or not on field emission properties. The resultsshow that the field emission properties of nanowires with large aspect ratio structures than nanowire structures and nano-octahedron smaller aspect ratio, which is a turn-on field5.2V/μm, the thresholdfield7.8V/μm, field enhancement factor is2438. And Fe doped In2O3nanowires have the optimumfield emission properties, their turn-on field is4.9V/μm, and Threshold field is7.5V/μm, Fieldenhancement factor is2672.