Transient Metal Alloy Oxidation Kinetics Visualized by In situ UHV-TEM Judith C. Yang, University of Pittsburgh, DMR 0706171 GOAL: Fundamental understanding of the complex nano-scale oxidation kinetics and energetics of metal alloys by using in situ ultra high vacuum transmission electron microscope (UHV-TEM); this research bridges the gap between surface science and bulk oxidation studies. METHOD: We are currently studying Cu x Ni 1-x as a model binary alloy system to gain insights into selective oxidation behavior. Cu and Ni are 100% solid-soluble down to ~300 °C but Cu 2 O and NiO show very limited miscibility. IMPACT: Advanced coating materials contain multiple elements to form a protective,slow-growing, thermodynamically stable oxide. This research will provide critical knowledge into the In situ oxidation of Cu (100) at T= 1000°C, pO 2 = 5 X 10 -4 Torr In situ oxidation of Cu-15 at %Au (100) at T= 600°C, pO 2 = 5 X 10 -4 Torr In situ oxidation of Cu-2.4 at% Ni (100) and Cu-13.6 at% Ni (100) at T= 600°C, pO 2 = 5 X 10 -4 Torr Only cube-on-cube oxide islands formed on Cu(100) surface Dendritic structured oxide islands formed on Cu-15%Au (100) surface Epitaxial oxide islands and
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Transient Metal Alloy Oxidation Kinetics Visualized by In situ UHV-TEM
Transient Metal Alloy Oxidation Kinetics Visualized by In situ UHV-TEM. Judith C. Yang, University of Pittsburgh, DMR 0706171. In situ oxidation of Cu (100) at T= 1000°C, pO 2 = 5 X 10 -4 Torr. In situ oxidation of Cu-15 at%Au (100) at T= 600°C, pO 2 = 5 X 10 -4 Torr. - PowerPoint PPT Presentation
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Transient Metal Alloy Oxidation Kinetics Visualized by In situ UHV-TEM
Judith C. Yang, University of Pittsburgh, DMR 0706171
GOAL: Fundamental understanding of the complex nano-scale oxidation kinetics and energetics of metal alloys by using in situ ultra high vacuum transmission electron microscope (UHV-TEM); this research bridges the gap between surface science and bulk oxidation studies.
METHOD: We are currently studying CuxNi1-x as a model binary alloy system to gain insights into selective oxidation behavior. Cu and Ni are 100% solid-soluble down to ~300 °C but Cu2O and NiO show very limited miscibility.
IMPACT: Advanced coating materials contain multiple elements to form a protective,slow-growing, thermodynamically stable oxide. This research will provide critical knowledge into the important parameters (surfaces, surfactants, strain, environmental conditions) that control selective oxidation and possibly a new paradigm of metal oxidation.
In situ oxidation of Cu (100) at T= 1000°C, pO2 = 5 X 10-4 Torr
In situ oxidation of Cu-15 at%Au (100) at T= 600°C, pO2 = 5 X 10-4 Torr
In situ oxidation of Cu-2.4 at% Ni (100) and Cu-13.6 at% Ni (100) at T= 600°C, pO2 = 5 X 10-4 Torr
Only cube-on-cube oxide islands formed on Cu(100) surface
Dendritic structured oxide islands formed on Cu-15%Au (100) surface
Epitaxial oxide islands and secondary nucleation of small oxide particles formed on Cu-Ni (100) surface
Transient Metal Alloy Oxidation Kinetics Visualized by In situ UHV-TEM
Judith C. Yang, University of Pittsburgh, DMR 0706171
Research Experience:
Graduate Education:
This grant provides the support for one female graduate student:
Ms. Zhuoqun Li (01/08-present)
High School Outreach:
Figure: 2nd annual PJAS and PECAP “Visualization of Nanotechnololgy” workshop. U. Pittsburgh. 10/11/08
The PI participates in the annual Pennsylvania Junior Academy of Science (PJAS) workshop where local high school students visit the the Nanofacility at U. Pittsburgh for hands-on demonstrations for a day, including electron microscopy. The recent PJAS includes Pitt Engineering Career Access Program (PECAP) students. PECAP is a U. Pittsburgh program to recruit, retain and graduate students from under-represented groups in STEM fields.
Undergraduate Research Experience:
This grant provides the support three undergraduate student (one female) for summer research and senior design project:
Ms. Katherine D. Rodger (5/09-present) Mr. Malay D. Shah (5/09-present) Mr. Steve Ziemak (5/08-5/09)
Malay D. Shah, Katherine D. Rodger and Zhuoqun Li (Left to right)