We report on synthesis and functional properties of ultra-thin oxide layers synthesized on metal surfaces by room temperature photon irradiation. We show that the impedance of a passive aluminum oxide film synthesized under ultraviolet photon irradiation is an order of magnitude larger than that of native oxide in a 0.5 M NaCl solution. Further, the structure and impedance of existing native oxide layers can be dramatically improved by minutes-long exposure to photon-irradiation. Depth profiling studies with X-ray photoelectron spectroscopy shows that chlorine uptake in UV-synthesized oxides, compared to that of native oxides, is reduced which can contribute to the improvement in corrosion resistance. The results are of significance to synthesis of ultra-thin passive layers on metal and alloy structures for environmental protection.
Revised: April 7, 2011 |
Published: June 30, 2008
Citation
Chang C., M.H. Engelhard, and S. Ramanathan. 2008.Superior Nanoscale Passive Oxide Layers Synthesized Under Photon Irradiation for Environmental Protection.Applied Physics Letters 92, no. 26:263103.PNNL-SA-58104.doi:10.1063/1.2952282