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Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
Published on: April 19, 2018
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Soft hydrogen plasma induced phase transition in monolayer and few-layer MoTe2
Haiyan Nan1, Jie Jiang2, Shaoqing Xiao1
1Engineering Research Center of IoT Technology Applications (Ministry of Education), Department of Electronic Engineering, Jiangnan University, Wuxi 214122, People's Republic of China.
Nanotechnology
|November 20, 2018
Summary
Soft hydrogen plasma treatment enables reversible phase engineering in molybdenum ditelluride (MoTe2) 2D materials. This facile technique allows tuning between semiconducting and metallic phases for advanced electronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Two-dimensional (2D) transition metal dichalcogenides (TMDs) exhibit distinct electronic phases.
- Phase transitions in materials like molybdenum ditelluride (MoTe2) are crucial for fundamental understanding and technological applications.
- Controlling phase transitions in 2D TMDs is essential for developing novel electronic devices.
Purpose of the Study:
- To develop a universal, scalable, and reversible method for phase engineering of 2D MoTe2.
- To investigate the mechanism behind the phase transition induced by soft hydrogen plasma treatment.
- To demonstrate the potential of phase-engineered MoTe2 in heterostructures and devices.
Main Methods:
- Soft hydrogen plasma treatment applied to monolayer and few-layer MoTe2.
- Characterization using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and field-effect transistor (FET) measurements.
- Preparation of 2D heterostructures with periodically patterned 2H and 1T' MoTe2 phases.
Main Results:
- Successfully induced a reversible phase transition from semiconducting 2H to metallic 1T' MoTe2 using hydrogen plasma.
- Confirmed the phase transition through detailed structural and electronic characterizations.
- Demonstrated that the phase transition is reversible via post-annealing and attributed it to hydrogen ion bombardment effects.
Conclusions:
- Soft hydrogen plasma treatment offers a robust and efficient approach for phase engineering of 2D MoTe2.
- The developed technique is applicable to both monolayer and few-layer MoTe2.
- This method facilitates the development of 2D optoelectronic, memory, and reconfigurable devices.
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