"Thermal Stability of Anodic Hafnium Oxide Nanotube Arrays"

Journal Article · Sat Jan 01 00:00:00 EST 2011 · Applied Surface Science

DOI:https://doi.org/10.1016/j.apsusc.2010.11.178· OSTI ID:1081641

Qiu, Xiaofeng ^[1]; Howe, Jane Y ^[1]; Mayer, Harry A ^[1]; Paranthaman, Mariappan Parans ^[1]; Tuncer, Enis ^[1]

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1. ORNL

Thermal stability of highly ordered Hafnium oxide, HfO2 nanotube arrays prepared through electrochemical anodization approach in the presence of ammonium fluoride is investigated in a temperature range of room temperature to 900 C in flowing Argon atmosphere. The formation of the HfO2 nanotube arrays was monitored by current density transient characteristics during anodization of hafnium metal foil. Morphologies of the as grown and post-annealed HfO2 nanotube arrays were analyzed by X-ray powder diffraction (XRD), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). Although monoclinic HfO2 is thermally stable up to 2000K in bulk, the morphology HfO2 nanotube arrays degraded at 900 C. Detailed X-ray photoelectron spectroscopy (XPS) study revealed that the thermal treatment significantly impact the composition and chemical environment of the core elements (Hf, O and F) of HfO2. Possible reasons for the degradation of the nanotube morphology were discussed based on XPS study and possible future improvements were suggested briefly.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Shared Research Equipment Collaborative Research Center
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1081641
• Journal Information: Applied Surface Science, Vol. 257, Issue 9; ISSN 0169-4332
• Country of Publication: United States
• Language: English