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Density Functional Theory Study On The Electronic Structure Of N- And P-Type Doped Srtio3 At Anodic Solid Oxide Fuel Cell Conditions, S. Suthirakun, Salai Ammal, G. Xiao, Fanglin Chen, Hans-Conrad Zur Loye, Andreas Heyden May 2015

Density Functional Theory Study On The Electronic Structure Of N- And P-Type Doped Srtio3 At Anodic Solid Oxide Fuel Cell Conditions, S. Suthirakun, Salai Ammal, G. Xiao, Fanglin Chen, Hans-Conrad Zur Loye, Andreas Heyden

Salai C. Ammal

The electronic conductivity and thermodynamic stability of mixed n-type and p-type doped SrTiO3 have been investigated at anodic solid oxide fuel cell (SOFC) conditions using density functional theory (DFT) calculations. In particular, constrained ab initio thermodynamic calculations have been performed to evaluate the phase stability and reducibility of various Nb- and Ga-doped SrTiO3 at synthesized and anodic SOFC conditions. The density of states (DOS) of these materials was analyzed to study the effects of n- and p-doping on the electronic conductivity. In agreement with experimental observations, we find that the transformation from 20% Nb-doped Sr-deficient SrTiO3 to a non-Sr-deficient phase …


The Effect Of Copt Crystallinity And Grain Texturing On Properties Of Exchange-Coupled Fe/Copt Systems, H. Oguchi, A. Zambano, M. Yu, Jason Hattrick-Simpers, D. Banerjee, Y. Liu, Z. Wang, J. Liu, S. Lofland, D. Josell, I. Takeuchi Mar 2015

The Effect Of Copt Crystallinity And Grain Texturing On Properties Of Exchange-Coupled Fe/Copt Systems, H. Oguchi, A. Zambano, M. Yu, Jason Hattrick-Simpers, D. Banerjee, Y. Liu, Z. Wang, J. Liu, S. Lofland, D. Josell, I. Takeuchi

Jason R. Hattrick-Simpers

The effect of the crystallinity and the grain texturing of CoPt hard layers on exchange coupled Fe/CoPt soft/hard magnetic systems was studied using gradient thickness multilayer thin films. We have studied the hard layer structures by transmission electron microscopy and x-ray diffraction, and characterized the exchange coupling interaction through magnetization loops obtained by the magneto-optical Kerr effect measurement. We found that exchange coupling strongly depends on the crystalline characteristics of the CoPt hard layer. There is correlation between the mixture of different grain orientations of the CoPt hard layer and coupling efficiency. In particular, interlayer coupling is enhanced when there …


Rapid Structural Mapping Of Ternary Metallic Alloy Systems Using The Combinatorial Approach And Cluster Analysis, C. Long, Jason Hattrick-Simpers, M. Murakami, R. Srivastava, I. Takeuchi, V. Karen, X. Li Mar 2015

Rapid Structural Mapping Of Ternary Metallic Alloy Systems Using The Combinatorial Approach And Cluster Analysis, C. Long, Jason Hattrick-Simpers, M. Murakami, R. Srivastava, I. Takeuchi, V. Karen, X. Li

Jason R. Hattrick-Simpers

We are developing a procedure for the quick identification of structural phases in thin film composition spread experiments which map large fractions of compositional phase diagrams of ternary metallic alloy systems. An in-house scanning x-ray microdiffractometer is used to obtain x-ray spectra from 273 different compositions on a single composition spread library. A cluster analysissoftware is then used to sort the spectra into groups in order to rapidly discover the distribution of phases on the ternary diagram. The most representative pattern of each group is then compared to a database of known structures to identify known phases. Using this method, …


Note: A Simple Thermal Gradient Annealing Unit For The Treatment Of Thin Films, C. Metting, Johnathan Bunn, Ellen Underwood, Yihao Zhu, G. Koley, T. Crawford, Jason Hattrick-Simpers Mar 2015

Note: A Simple Thermal Gradient Annealing Unit For The Treatment Of Thin Films, C. Metting, Johnathan Bunn, Ellen Underwood, Yihao Zhu, G. Koley, T. Crawford, Jason Hattrick-Simpers

Jason R. Hattrick-Simpers

A gradient annealing cell has been developed for the high-throughput study of thermalannealing effects on thin-film libraries in different environments. The inexpensive gradientannealing unit permits temperature gradients as large as 28 °C/mm and can accommodate samples ranging in length from 13 mm to 51 mm. The system was validated by investigating the effects of annealing temperature on the crystallinity, resistivity, and transparency of tin-doped indium oxide deposited on a glass substrate by magnetron sputtering. The unit developed in this work will permit the rapid optimization of materials properties such as crystallinity, homogeneity, and conductivity across a variety of applications.


Characterization Of Magnetic Degradation Mechanism In A High Neutron-Flux Environment, Adib Samin, Jie Qiu, Jason Hattrick-Simpers, Liyang Dai-Hattrick, Yuan Zheng, Lei Cao Mar 2015

Characterization Of Magnetic Degradation Mechanism In A High Neutron-Flux Environment, Adib Samin, Jie Qiu, Jason Hattrick-Simpers, Liyang Dai-Hattrick, Yuan Zheng, Lei Cao

Jason R. Hattrick-Simpers

No abstract provided.


Optical Cell For Combinatorial In Situ Raman Spectroscopic Measurements Of Hydrogen Storage Materials At High Pressures And Temperatures, Jason Hattrick-Simpers, Wilbur Hurst, Sesha Srinivasan, James Maslar Mar 2015

Optical Cell For Combinatorial In Situ Raman Spectroscopic Measurements Of Hydrogen Storage Materials At High Pressures And Temperatures, Jason Hattrick-Simpers, Wilbur Hurst, Sesha Srinivasan, James Maslar

Jason R. Hattrick-Simpers

An optical cell is described for high-throughput backscattering Raman spectroscopic measurements of hydrogen storagematerials at pressures up to 10 MPa and temperatures up to 823 K. High throughput is obtained by employing a 60 mm diameter × 9 mm thick sapphire window, with a corresponding 50 mm diameter unobstructed optical aperture. To reproducibly seal this relatively large window to the cell body at elevated temperatures and pressures, a gold o-ring is employed. The sample holder-to-window distance is adjustable, making this cell design compatible with optical measurement systems incorporating lenses of significantly different focal lengths, e.g., microscope objectives and single element …