Sökning: "Metastable phases"

Visar resultat 6 - 10 av 49 avhandlingar innehållade orden Metastable phases.

1. 6. Controlled growth of metastable Ta3N5 semiconducting films

   Författare :Jui-Che Chang; Ching-Lien Hsiao; Jens Birch; Grzegorz Greczynski; Martin Rudolph; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The semiconductor tritantalum pentanitride (Ta3N5) is a promising material for green energy applications, specifically in the photoelectrolysis of water to produce oxygen and hydrogen. With a bandgap of approximately 2 eV, Ta3N5 is well-suited for efficient solar light absorption across a broad spectrum, and its band positions align favorably with the redox potential of water. LÄS MER

3. 7. Controlling the Formation and Stability of Alumina Phases

   Författare :Jon Martin Andersson; Ulf Helmersson; Eric Kay; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thin films; alumina; magnetron sputtering; phase stability; density functional theory; Material physics with surface physics; Materialfysik med ytfysik;

   Sammanfattning : In this work, physical phenomena related to the growth and phase formation of alumina, Al2O3, are investigated by experiments and computer calculations. Alumina finds applications in a wide variety of areas, due to many beneficial properties and several existing crystalline phases. LÄS MER

4. 8. Structural, Kinetic and Thermodynamic Aspects of the Crystal Polymorphism of Substituted Monocyclic Aromatic Compounds

   Författare :Michael Svärd; Åke Rasmuson; Hugo Meekes; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polymorphism; crystallization; thermodynamics; kinetics; nucleation; crystallography; solubility; phase equilibria; polymorphic transformation; solution history; metastable zone; classical theory of nucleation; two-step theory of nucleation; cluster; crystal structure prediction; lattice energy; molecular mechanics; force field; electrostatic potential; potential energy hypersurface; m-aminobenzoic acid; m-hydroxybenzoic acid; Chemical engineering; Kemiteknik;

   Sammanfattning : This work concerns the interrelationship between thermodynamic, kinetic and structural aspects of crystal polymorphism. It is both experimental and theoretical, and limited with respect to compounds to substituted monocyclic aromatics. LÄS MER

5. 9. Metastable orthorhombic Ta3N5 thin films grown by magnetron sputter epitaxy

   Författare :Jui-Che Chang; Ching-Lien Hsiao; Jens Birch; Grzegorz Greczynski; Denis Music; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The semiconductor tritantalum pentanitride (Ta3N5) is a promising green-energy material for photoelectrolyzing water to produce oxygen and hydrogen owing to its proper bandgap of 2.0 ± 0.2 eV and band positions to redox potential of water. LÄS MER

7. 10. Metastable Alumina from Theory: Bulk, Surface, and Growth of κ-Al2O3

   Författare :Carlo Ruberto; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; density-functional theory; structure; cutting tools; plane waves; first principles; stability; one-dimensional electron gas; DFT; Tasker s rules; ionic crystals; polar surfaces; adsorption; pseudopotentials; Pauling s rules; bonding; surface states; TiC; ceramic materials;

   Sammanfattning : Aluminas are materials of high technological importance that show a fascinating structural flexibility, with a large amount of different phases (alpha, gamma, eta, delta, kappa, chi, ...) and phase transitions at relatively high temperatures. LÄS MER