纳米粒子尺寸效应引起的内层电子结合能位移

用XPS测定了氩离子溅射前后的Pt-PVP纳米粒子和TiO2、ZnO及SiO2纳米粒子的内层电子结合能, 并与其对应的体材料进行了比较. 结果表明, Ar+溅射前Pt-PVP的Pt 4f结合能比体材料Pt的稍低, 但Ar+溅射后由于PVP包覆层被除去, 裸露的Pt 纳米粒子的结合能明显高于Pt体材料. 与非纳米氧化物比较, 纳米氧化物TiO2、ZnO 和SiO2的内层电子结合能也向高结合能方向位移, 其位移大小的顺序为TiO2

Core Level Binding Energy Shifts Caused by Size Effect of Nanoparticles

XPS spectra were used to determine the binding energies for Pt-PVP nanoparticles before and after Ar+ ion sputtering, as well as for some oxides nanoparticles (TiO2, ZnO, and SiO2). The binding energies of the nanoparticles were compared with those of the corresponding bulk materials. The results showed that, compared with bulk Pt, the Pt 4f binding energy of Pt-PVP nanoparticles before Ar + ion sputtering shifted to lower binding energy side. After Ar+ sputtering, the PVP on Pt nanoparticles was sputtered away and the Pt nanoparticles became bare, the binding energy shifted to higher binding energy side. By comparison with the bulk oxides, the binding energies of TiO2, ZnO, and SiO2 nanoparticles also shifted to the higher binding energy side, and the magnitude of binding energy shift was in the order of TiO2