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Abstract Device engineering based on the tunable electronic properties of ternary transition metal dichalcogenides has recently gained widespread research interest. In this work, monolayer ternary telluride core/shell structures are synthesized using a one‐step chemical vapor deposition process with rapid cooling. The core region is the tellurium‐rich WSe2−2xTe2xalloy, while the shell is the tellurium‐poor WSe2−2yTe2yalloy. The bandgap of the material is ≈1.45 eV in the core region and ≈1.57 eV in the shell region. The lateral gradient of the bandgap across the monolayer heterostructure allows for the fabrication of heterogeneous transistors and photodetectors. The difference in work function between the core and shell regions leads to a built‐in electric field at the heterojunction. As a result, heterogeneous transistors demonstrate a unidirectional conduction and strong photovoltaic effect. The bandgap gradient and high mobility of the ternary telluride core/shell structures provide a unique material platform for novel electronic and photonic devices.
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Separation of Tellurium from Metal Chalcogenides through Mild Anhydrous Chlorination
Abstract The separation of tellurium from cadmium telluride is examined using a unique combination of mild, anhydrous chlorination and complexation of the subsequent tellurium tetrachloride with 3,5‐di‐tert‐butylcatecholate ligands (dtbc). The resulting tellurium complex, Te(dtbc)2, is isolated in moderate yield and features a 103to 104reduction in cadmium content, as provided by XRF and ICP‐MS analysis. Similar results were obtained from zinc telluride. A significant separation between Te, Se, and S was observed after treating a complex mixture of metal chalcogenides with this protocol. These three tunable steps can be applied for future applications of CdTe photovoltaic waste.
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- Award ID(s):
- 1925708
- PAR ID:
- 10385151
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 29
- Issue:
- 7
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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