The Size Dependence Of The Binding Energy Shift For Cu Nanoparticles

It has been found that the Surface-volume ratio of copper nanoparticles and itsparticle films is larger than the copper bulk, the surface of copper nanoparticles and itsparticle films has a large number of low coordination atoms, and the number of lowcoordination atoms for the bulk almost can be ignored, the low coordination atoms aredifferent with atoms Cu bulk. So, it can make the copper nanoparticles have manyanomalous properties, which show a wide application prospect.It is know that the band structure of materials is associated with its performanceabout band theory, such as electrical conductivity. Because the size of coppernanoparticles and its particle films is limited with their bulk, their band structure willbe adjusted, and their band gap and the binding energy will be change with the size ofcopper nanoparticles and its particle films. The binding energy shift of each energylevel of the copper nanoparticles and its particle films can affect their performance. So,it is quite meaningful to study the effect of size about the copper nanoparticles.In this thesis, the binding energy shift of copper nanoparticles and its particlefilms with different size has been analyzed on the framework of bondorder-length-strength (BOLS) correlation with the analysis of the XPS and AES. Themajor progresses are summarized as following:(1) Theoretical reproduction of the measured spectroscopic data derived that theCu2p3/2shifts positively by1.70eV from the atomic value of931.00eV to the bulkvalue of932.70eV. The shift of binding energy is due to the Surface-volume ratio ofcopper nanoparticles is larger than the copper bulk, the surface of copper nanoparticlesand its particle films has a large number of low coordination atoms, which makes achange about the bond length and the bond energy, and modify electronic Hamiltonianin the crystal lattice.(2) It is study that the affect of size about Cu2p3/2and3d5/2binding energy shiftof copper nanoparticles growth on HOPG, CYL and Al2O3substrate with the theory ofBOLS, XPS and AES.The result of theoretical analysis show that the positive shift of binding energymainly because of the affect of size. It is clarified that the positive energy shiftsoriginate from the size-induced bond contraction, and illustrates that the dominance ofthe broken-bond-induced local strain and quantum entrapment perturbs theHamiltonian and finally causes the positive shift. Exercises exemplify the enhancedcapabilities of XPS and AES in determining quantitative information regarding the evolution of the local bond length, bond energy, binding energy density, and atomiccohesive energy, with the coordination number and chemical enviroment. This is notonly beneficial to solve the existing theory in other nanomaterials encountereddifficulties, but also a deeper understanding and mastering physics in nanometer scale,with some low dimensional nanostructures device for the future of designoptimization and performance study provide theoretical guidance and experimentalbasis.