Periodic Reporting for period 1 - CHEM2D (Chemistry of 2D materials: Intercalation and surface functionalization)
Periodo di rendicontazione: 2019-06-01 al 2021-05-31
The physical properties of 2D materials are extremely sensitive to the number of layers and the interlayer distance, governed by weak van der Waals interactions. Consequently, the fine-tuning of these interactions permit to control the properties of the material.
The main goal of this project was to synthesize new 2D materials (based on transition-metal chalcogenides) with tailored transport and optoelectronic properties, by controlling interlayer interactions (via intercalation) and the surfaces of the crystals (via functionalization). Intercalation of guest species, such as alkali metals, act as spacers and can provide a very large doping level by conducting charge carriers into the adjacent conducting layer. Furthermore, the increase in layer separation produces a weaker interaction between layers, resulting in each layer behaving as an almost isolated single layer.
By using nanofabrication techniques, synthesized 2D materials can be integrated into electronic devices.
The main goal of this project was to synthesize new 2D materials (based on transition-metal chalcogenides) with tailored transport and optoelectronic properties, by controlling interlayer interactions (via intercalation) and the surfaces of the crystals (via functionalization). Intercalation of guest species, such as alkali metals, act as spacers and can provide a very large doping level by conducting charge carriers into the adjacent conducting layer. Furthermore, the increase in layer separation produces a weaker interaction between layers, resulting in each layer behaving as an almost isolated single layer.
By using nanofabrication techniques, synthesized 2D materials can be integrated into electronic devices.
The technical report contains the main results of the project, which can be summarized in the following points:
- Exfoliation of MoS2 crystal was successfully performed by microwave-hydrothermal procedure.
- Two alternative strategies of intercalation were explored throughout this work: (1) Wet-chemistry routes: lithium was intercalated in metal chalcogenides by using n-butyl lithium in hexane or lithium metal/ naphthalene in THF.(2) Electrochemistry approach for the preparation of intercalated 2D-materials. Lithium or sodium metal anode intercalates into the 2D material cathode through an ionically conducting liquid/solid electrolyte through an external bias.
- Exfoliation of MoS2 crystal was successfully performed by microwave-hydrothermal procedure.
- Two alternative strategies of intercalation were explored throughout this work: (1) Wet-chemistry routes: lithium was intercalated in metal chalcogenides by using n-butyl lithium in hexane or lithium metal/ naphthalene in THF.(2) Electrochemistry approach for the preparation of intercalated 2D-materials. Lithium or sodium metal anode intercalates into the 2D material cathode through an ionically conducting liquid/solid electrolyte through an external bias.
Electrochemical approach can be efficiently used for the preparation of intercalated 2D-materials. The easily control of the doping level by this method allows new possibilities for bespoke 2D material design.
The synthesized materials will be integrated into electronic devices such as photodetectors or solar cells.
The synthesized materials will be integrated into electronic devices such as photodetectors or solar cells.