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Abstract We report the synthesis of a soluble precursor that transforms into crystalline SnSe at 200 °C. This transformation temperature is significantly lower than the 270–350 °C range of previously reported tin selenide precursors. This precursor is synthesized by reacting tin with dimethyl diselenide and we identify the precursor as tin(IV) methylselenolate using a combination of mass spectrometry, Raman spectroscopy, and nuclear magnetic resonance spectroscopy. We then chemically treat PbSe colloidal nanocrystals with this precursor and subject them to mild annealing. We characterize the chemical and structural changes during this processing using infrared spectroscopy, aberration‐corrected scanning transmission electron microscopy, and X‐ray photoelectron spectroscopy. These characterization studies indicate the successful formation of a SnSe‐like material that fills the interstitial space between the PbSe nanocrystal cores. We find that the electrical conductivity of these nanocrystal films is comparable to other excellent treatments used to improve charge transport. This excellent charge transport demonstrates the utility of tin(IV) methylselenolate as a conductive “glue” between nanocrystals.
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Determining the oxidation stability of SnSe under atmospheric exposure
Abstract Understanding surface stability becomes critical as 2D materials like SnSe are developed for piezoelectric and optical applications. SnSe thin films deposited by molecular beam epitaxy showed no structural changes after a two-year exposure to atmosphere, as confirmed by X-ray diffraction and Raman spectroscopy. X-ray photoelectron spectroscopy and reflectivity show a stable 3.5 nm surface oxide layer, indicating a self-arresting oxidative process. Resistivity measurements show an electrical response dominated by SnSe post-exposure. This work shows that SnSe films can be used in ambient conditions with minimal risk of long-term degradation, which is critical for the development of piezoelectric or photovoltaic devices. Graphical Abstract
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- PAR ID:
- 10543900
- Publisher / Repository:
- Cambridge University Press (CUP)
- Date Published:
- Journal Name:
- MRS Communications
- Volume:
- 14
- Issue:
- 5
- ISSN:
- 2159-6867
- Format(s):
- Medium: X Size: p. 1000-1006
- Size(s):
- p. 1000-1006
- Sponsoring Org:
- National Science Foundation
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