Designed CVD growth of graphene via process engineering

Area of Science:

• Materials Science
• Surface Science
• Nanotechnology

Background:

• Graphene exhibits exceptional properties, driving research into scalable and high-quality synthesis methods.
• Chemical Vapor Deposition (CVD) is a key technique for graphene production, with ongoing advancements in controlling its growth.
• Understanding and manipulating the elementary steps of CVD is crucial for achieving desired graphene characteristics.

Purpose of the Study:

• To present recent progress in controlled surface growth of graphene and 2D hybrids using rational designs of CVD elementary processes.
• To demonstrate how process engineering of CVD steps can lead to precise control over graphene synthesis.
• To provide insights into the fundamental mechanisms governing graphene formation via CVD.

Main Methods:

• Focus on process engineering of four main CVD elementary steps: adsorption/decomposition, diffusion/dissolution, segregation, and nucleation/growth.
• Utilized various metal catalysts (Ni, Co, Mo, Cu) and alloys (Cu-Ni) to manipulate elementary steps.
• Implemented techniques like alloying, segregation control, two-temperature zone systems, and wrinkle engineering.

Main Results:

• Demonstrated complete blocking of segregation using Mo catalyst for monolayer graphene.
• Achieved enhanced thickness control using synergetic Cu-Ni alloy for segregation.
• Synthesized nitrogen-doped graphene with tunable profiles via cosegregation.
• Produced high-quality Bernal stacked bilayer graphene using a two-temperature zone system.
• Fabricated graphene nanoribbon arrays and mosaic graphene with p-n junctions.

Conclusions:

• Process engineering of CVD elementary steps offers precise control over graphene and 2D hybrid synthesis.
• A deep understanding of CVD growth mechanisms is essential for advancing graphene applications.
• The presented strategies provide a unique insight into graphene CVD, paving the way for tailored material properties.