| Popis: |
Amorphous semiconductors have proven useful as a means of data storage, but the behavior of such materials in exotic configurations remains difficult to predict. We sought to determine what effect forcing amorphous selenium to adopt a nanowire geometry would have on its atomic structure. We achieved a nanowire geometry by depositing selenium from solution into the pores of an SBA-15 thin silica film with pores approximately 2 nanometers wide. X-ray Absorption Fine Spectroscopy (XAFS) was performed to determine the atomic coordination geometry. We also attempted to perform ab initio simulations of the same materials using the FEFF 9.03 program. The spectra of the nanowire and bulk samples showed no appreciable difference in the extended region, and an 87.3% decrease in the effective coordination number in the near-edge region may be attributed to trivial boundary effects. These results strongly suggest that the structure of amorphous selenium is not greatly affected by confinement, and memory-storage devices based on this geometry may be feasible. |
