Mapping of Defects in Individual Silicon Nanocrystals Using Real-Space Spectroscopy
| Autor: | George V. Nazin, Vancho Kocevski, Sheng-Kuei Chiu, Jon M. Mills, Andrea M. Goforth, Christian F. Gervasi, Ariel E. Rosenfield, Jan Rusz, Benjamen N. Taber, Olle Eriksson, Dmitry A. Kislitsyn |
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| Rok vydání: | 2016 |
| Předmět: |
Materials science
business.industry Scanning tunneling spectroscopy Nanotechnology 02 engineering and technology Electronic structure 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Spectral line 0104 chemical sciences law.invention Delocalized electron Semiconductor Nanocrystal law Chemical physics General Materials Science Physical and Theoretical Chemistry Scanning tunneling microscope 0210 nano-technology business Spectroscopy Den kondenserade materiens fysik |
| Zdroj: | The journal of physical chemistry letters. 7(6) |
| ISSN: | 1948-7185 |
| Popis: | The photophysical properties of silicon semiconductor nanocrystals (SiNCs) are extremely sensitive to the presence of surface chemical defects, many of which are easily produced by oxidation under ambient conditions. The diversity of chemical structures of such defects and the lack of tools capable of probing individual defects continue to impede understanding of the roles of these defects in SiNC photophysics. We use scanning tunneling spectroscopy to study the impact of surface defects on the electronic structures of hydrogen-passivated SiNCs supported on the Au(111) surface. Spatial maps of the local electronic density of states (LDOS) produced by our measurements allowed us to identify locally enhanced defect-induced states as well as quantum-confined states delocalized throughout the SiNC volume. We use theoretical calculations to show that the LDOS spectra associated with the observed defects are attributable to Si-O-Si bridged oxygen or Si-OH surface defects. |
| Databáze: | OpenAIRE |
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