Synthesis and Optical Properties of Large-Area Single-Crystalline 2D Semiconductor WS2Monolayer from Chemical Vapor Deposition

ABSTRACTIn this work, we report the synthesis and characterization of three dimensional heterostructures graphene nanostructures (HGN) comprising continuous large area graphene layers and ZnO nanostructures, fabricated via chemical vapor deposition. Characterization of large area HGN demonstrates that it consists of 1-5 layers of graphene, and exhibits high optical transmittance and enhanced electrical conductivity. Electron microscopy investigation of the three dimensional heterostructures shows that the morphology of ZnO nanostructures is highly dependent on the growth temperature. It is observed that ordered crystalline ZnO nanostructures are preferably grown along the <0001> direction. Ultraviolet spectroscopy indicates that the CVD grown HGN layers has excellent optical properties. A combination of electrical and optical properties of graphene and ZnO building blocks in ZnO based HGN provides unique characteristics for opportunities in future optoelectronic devices.

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Synthesis of Large-Area Monolayer and Few-Layer MoSe2 Continuous Films by Chemical Vapor Deposition without Hydrogen assisted and Formation Mechanism

Nanoscale ◽

10.1039/d1nr00552a ◽

2021 ◽

Author(s):

Hui Yan ◽

Tong Yu ◽

Heng Li ◽

Zhuocheng Li ◽

Haitao Tang ◽

...

Keyword(s):

Optical Properties ◽

Chemical Vapor Deposition ◽

Layered Structure ◽

Vapor Deposition ◽

Large Scale ◽

Chemical Vapor ◽

Controlled Synthesis ◽

Two Dimensional ◽

Large Area ◽

High Quality

Two dimensional (2D) MoSe2 with layered structure has attracted extensive research due to its excellent electronic and optical properties. Controlled synthesis of large-scale and high-quality MoSe2 is highly desirable but...

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Thermodynamics Controlled Sharp Transformation from InP to GaP Nanowires via Introducing Trace Amount of Gallium

Nanoscale Research Letters ◽

10.1186/s11671-021-03505-2 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Zhenzhen Tian ◽

Xiaoming Yuan ◽

Ziran Zhang ◽

Wuao Jia ◽

Jian Zhou ◽

...

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Driving Force ◽

Chemical Vapor ◽

Chemical Vapor Deposition Method ◽

Nanowire Growth ◽

Calphad Approach ◽

Deposition Method ◽

Large Area ◽

Growth Phenomenon

AbstractGrowth of high-quality III–V nanowires at a low cost for optoelectronic and electronic applications is a long-term pursuit of research. Still, controlled synthesis of III–V nanowires using chemical vapor deposition method is challenge and lack theory guidance. Here, we show the growth of InP and GaP nanowires in a large area with a high density using a vacuum chemical vapor deposition method. It is revealed that high growth temperature is required to avoid oxide formation and increase the crystal purity of InP nanowires. Introduction of a small amount of Ga into the reactor leads to the formation of GaP nanowires instead of ternary InGaP nanowires. Thermodynamic calculation within the calculation of phase diagrams (CALPHAD) approach is applied to explain this novel growth phenomenon. Composition and driving force calculations of the solidification process demonstrate that only 1 at.% of Ga in the catalyst is enough to tune the nanowire formation from InP to GaP, since GaP nucleation shows a much larger driving force. The combined thermodynamic studies together with III–V nanowire growth studies provide an excellent example to guide the nanowire growth.

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