Room-temperature single-electron tunnelling in surfactant stabilized iron oxide

2019-07-01 05:10:13

particles acid electron Iron oxide

责任者: Moore, R.G.C.;Evans, S.D.;Shen, T.;Hodson, C.E.C. 单位: Univ of Leeds, Leeds, UK 来源出处: Physica E: Low-Dimensional Systems and Nanostructures,2001,9(2):253-261 摘要: Iron oxide nanoparticles have been synthesized by the reduction of FeCl3·6H2O and FeCl2·4H2O (mass ratio 2:1) in propan-2-ol. The particles were stabilized by the addition of lauric acid and the resultant particles could be readily dispersed in chloroform. Room-temperature single-electron tunnelling through these iron oxide particles has been achieved (to our knowledge) for the first time, using an STM tip-particle-substrate double junction. Characterization of the particles by XPS and FTIR show that they are Fe2O3, or possibly Fe3O4 with an outer layer of Fe2O3, coated with a carboxylic acid monolayer. The particle diameter given by TEM is of the order of 5.0±0.9 nm. From the Coulomb staircase behaviour observed in the I-V curves, we estimate a nanoparticle capacitance of 6.7×10-19 F which is in agreement with that expected for particles of this size. 关键词: Nanostructured materials;Iron oxides;Electron tunneling;Surface active agents;X ray photoelectron spectroscopy;Fourier transform infrared spectroscopy;Transmission electron microscopy;Current voltage characteristics;Synthesis (chemical);Single electron tunneling;Coulomb blockade;Lauric acid