Abstract
Electron transport in the porous nano-structured media was investigated experimentally, and the results were examined by a random walk simulation. TiO2 nano-particles with an average diameter of about 150 nm ware prepared by sol–gel approach and spin coated on the glass substrate. Effects of porosity on the diffusion coefficient of the prepared nano-porous TiO2 were investigated by Hall measurement. Geometrically disordered nanoparticle was generated and utilized for simulations. Dependency of the diffusion coefficient on the network porosity was completely studied by assuming that the traps are placed mainly on the surface of the nanoparticles. It was shown in this study that the diffusion coefficient decreases by increasing the porosity. In this study, fabrication process was step by step simulated for the first time to compare the experimental achievements and the results of the simulation. Such comparison confirms the surface distribution of the traps in porous materials.
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The authors would like to acknowledge the partial financial support of university of Tehran for this research under grant number 3/1/27746.
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Abdi, N., Abdi, Y., Nedaaee Oskoee, E. et al. Electron diffusion in trap-contained 3D porous nanostructure: simulation and experimental investigation. J Nanopart Res 16, 2308 (2014). https://doi.org/10.1007/s11051-014-2308-3
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DOI: https://doi.org/10.1007/s11051-014-2308-3