Realization of vertical metal semiconductor heterostructures via solution phase epitaxy.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30190475.
- Also identified by DOI 10.1038/s41467-018-06053-z and PMC identifier 6127337.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The creation of crystal phase heterostructures of transition metal chalcogenides, e.g., the 1T/2H heterostructures, has led to the formation of metal/semiconductor junctions with low potential barriers. Very differently, post-transition metal chalcogenides are semiconductors regardless of their phases. Herein, we report, based on experimental and simulation results, that alloying between 1T-SnS<sub>2</sub> and 1T-WS<sub>2</sub> induces a charge redistribution in Sn and W to realize metallic Sn<sub>0.5</sub>W<sub>0.5</sub>S<sub>2</sub> nanosheets. These nanosheets are epitaxially deposited on surfaces of semiconducting SnS<sub>2</sub> nanoplates to form vertical heterostructures. The ohmic-like contact formed at the Sn<sub>0.5</sub>W<sub>0.5</sub>S<sub>2</sub>/SnS<sub>2</sub> heterointerface affords rapid transport of charge carriers, and allows for the fabrication of fast photodetectors. Such facile charge transfer, combined with a high surface affinity for acetone molecules, further enables their use as highly selective 100 ppb level acetone sensors. Our work suggests that combining compositional and structural control in solution-phase epitaxy holds promises for solution-processible thin-film optoelectronics and sensors.