ZnO films are grown on c-sapphire substrates by laser molecular beam epitaxy.The band offsets of the ZnO/Al_(2)O_(3) heterojunction are studied by in situ x-ray photoelectron spectroscopy.The valence band of Al_(2)O_(...ZnO films are grown on c-sapphire substrates by laser molecular beam epitaxy.The band offsets of the ZnO/Al_(2)O_(3) heterojunction are studied by in situ x-ray photoelectron spectroscopy.The valence band of Al_(2)O_(3) is found to be 3.59±0.05 eV below that of ZnO.Together with the resulting conduction band offset of 2.04±0.05 eV,this indicates that a type-I staggered band line exists at the ZnO/Al_(2)O_(3) heterojunction.展开更多
Using first-principles calculations,we predict that a single C_(2)H_(4) or C_(5)H_(5) molecule can form a stable complex with two rare earth metals such as La,Eu,and Ho.The La_(2)C_(2)H4 complex then absorbs up to six...Using first-principles calculations,we predict that a single C_(2)H_(4) or C_(5)H_(5) molecule can form a stable complex with two rare earth metals such as La,Eu,and Ho.The La_(2)C_(2)H4 complex then absorbs up to sixteen hydrogen molecules,reaching a gravimetric storage capacity of 9.5wt%by adding a rare-earth metal atom,The results show that Eu-4f electrons have little impact on the hydrogen adsorption.The nature of bonding between Eu and H_(2) is due to the hybridization of Eu-5d with the H-1s orbital.展开更多
基金Supported by the Major Instrumentation Special of the Ministry of Science and Technology of China under Grant No 2011YQ130018Open Foundation of Joint Laboratory for Extreme Conditions Matter Properties,Southwest University of Sci-ence and Technology and Research Center of Laser Fusion,CAEP(No 12zxjk06)the National High-Technology Research and Development Program of China.
文摘ZnO films are grown on c-sapphire substrates by laser molecular beam epitaxy.The band offsets of the ZnO/Al_(2)O_(3) heterojunction are studied by in situ x-ray photoelectron spectroscopy.The valence band of Al_(2)O_(3) is found to be 3.59±0.05 eV below that of ZnO.Together with the resulting conduction band offset of 2.04±0.05 eV,this indicates that a type-I staggered band line exists at the ZnO/Al_(2)O_(3) heterojunction.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11074176,10976019the Research Fund for the Doctoral Program of Higher Education of China under Grant No 20100181110080.
文摘Using first-principles calculations,we predict that a single C_(2)H_(4) or C_(5)H_(5) molecule can form a stable complex with two rare earth metals such as La,Eu,and Ho.The La_(2)C_(2)H4 complex then absorbs up to sixteen hydrogen molecules,reaching a gravimetric storage capacity of 9.5wt%by adding a rare-earth metal atom,The results show that Eu-4f electrons have little impact on the hydrogen adsorption.The nature of bonding between Eu and H_(2) is due to the hybridization of Eu-5d with the H-1s orbital.
