A new process developed by researchers at Brown University uses silicon telluride to produce multilayered two-dimensional semiconductor materials in a variety of shapes and orientations.
A Silicon-Based Two-Dimensional Chalcogenide: Growth of Si2Te3 Nanoribbons and Nanoplates
Sean Keuleyan , Mengjing Wang , Frank R. Chung , Jeffrey Commons , and Kristie J. Koski
Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
Nano Lett., Article ASAP
DOI: 10.1021/nl504330g
Sean Keuleyan , Mengjing Wang , Frank R. Chung , Jeffrey Commons , and Kristie J. Koski
Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
Nano Lett., Article ASAP
DOI: 10.1021/nl504330g
We report the synthesis of high-quality single-crystal two-dimensional, layered nanostructures of silicon telluride, Si2Te3,
in multiple morphologies controlled by substrate temperature and Te
seeding. Morphologies include nanoribbons formed by VLS growth from Te
droplets, vertical hexagonal nanoplates through vapor–solid
crystallographically oriented growth on amorphous oxide substrates, and
flat hexagonal nanoplates formed through large-area VLS growth in liquid
Te pools. We show the potential for doping through the choice of
substrate and growth conditions. Vertical nanoplates grown on sapphire
substrates, for example, can incorporate a uniform density of Al atoms
from the substrate. We also show that the material may be modified after
synthesis, including both mechanical exfoliation (reducing the
thickness to as few as five layers) and intercalation of metal ions
including Li+ and Mg2+, which suggests
applications in energy storage materials. The material exhibits an
intense red color corresponding to its strong and broad interband
absorption extending from the red into the infrared. Si2Te3 enjoys chemical and processing compatibility with other silicon-based material including amorphous SiO2
but is very chemically sensitive to its environment, which suggests
applications in silicon-based devices ranging from fully integrated
thermoelectrics to optoelectronics to chemical sensors.
No comments:
Post a Comment