Sökning: "dopant positions"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden dopant positions.

1. 1. Dopant inclusion and isomorphism of KTP : a nonlinear optical material

   Författare :Stefan Norberg; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; potassium titanium phosphate; dopant positions; single crystal X-ray diffraction; KSbOGeO4-KSbOSiO4; KTP; KTiOP4; TiP2O7 superstructure;

   Sammanfattning : .... LÄS MER

3. 2. Correlating Nanostructure and Electronic Properties of Organic Semiconductors by Electron Microscopy

   Författare :Gustav Persson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 3D; transmission electron microscopy; clustering; molecular dopant; nanostructure; structure-property correlation; visualisation; concentration; organic semiconductor;

   Sammanfattning : Organic semiconductors enable fabrication and efficient processing of electronic devices with light weight, mechanical flexibility and tuneable properties. Despite significant progress in the last decades, efficiencies and long-term stabilities of these systems still need to be improved. LÄS MER

4. 3. Point defects and ion conduction in solid oxides: a first-principles case study of La2Zr2O7

   Författare :Joakim Nyman; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; proton; self compensation; hydrogen economy; DFT; La2Zr2O7; acceptor doping; lanthanum zirconate; oxygen vacancy; SOFC; pyrochlore; point defect; trapping; computational methods; solid oxide; charge compensation; first principles; ion conduction; solid oxide fuel cell; ceramic electrolyte; defect cluster; fuel cell; hydrogen;

   Sammanfattning : In the endeavor to attain a clean environment and sustainable energy consumption, the notion of a future hydrogen economy stands out as one of the grandest visions. Striving for this vision, a critical task lies in optimizing the performance of the fuel-cell devices responsible for extracting electric power from the energy stored in hydrogen molecules. LÄS MER

5. 4. Hydrogen in oxides: a density-functional study of thermodynamic and kinetic aspects

   Författare :Mårten Björketun; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; proton conduction; La$_2$Zr$_2$O$_7$; protonation; kinetic Monte Carlo; density functional theory.; BaZrO$_3$; hydrogen oxide systems; electronic structure;

   Sammanfattning : Many solid oxides, especially those possessing a perovskite structure, exhibit significant proton conductivity when being acceptor doped and placed in hydrogen-containing atmospheres. Consequently, they have attracted attention foruse as solid membranes in electrochemical devices such as gas sensors, steam electrolyzers and fuel cells. LÄS MER

7. 5. Proton conductivity of lanthanum and barium zirconate: Microscale aspects on first-principles basis

   Författare :Joakim Nyman; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; first principles; trapping; conductivity; grain boundary; segregation; pyrochlore; space charge; solid oxide fuel cell; depletion; electrolyte; La2Zr2O7; oxygen vacancy; BaZrO3; proton; DFT; point defect; perovskite; acceptor;

   Sammanfattning : Fuel cells are devices which convert chemical energy into electrical energy cleanly and efficiently. Development of fuel cells compatible with hydrocarbon fuels would make more efficient use of present fossil and renewable fuels, and also enable progress towards a future hydrogen economy. LÄS MER