Multilayer Graphene Shear Strength via Covalent Interlayer Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The weak van der Waals interlayer forces between stacked graphene layers result in low shear strength, limiting the practical applications of multi-layer graphene due to the lack of control over interlayer bonding and twist angles.
Innovation Solution
Controlled interlayer twist angles and specialized treatments, such as hydrogenation or fluorination, are used to create covalent bonds between adjacent graphene layers, enhancing the mechanical properties of multi-layer graphene structures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If multiple graphene layers are stacked together to achieve macroscopic thickness, then the material becomes suitable for practical applications, but the shear strength decreases due to weak van der Waals interlayer forces
Solution Approach 1:
The patent changes the bonding parameter between graphene layers from weak van der Waals forces to strong covalent bonds through chemical functionalization (hydrogenation, fluorination, or other methods). This transforms the interlayer interaction mechanism, enabling multi-layer stacks to maintain high shear strength while achieving macroscopic thickness for practical applications.
Solution Approach 2:
The patent creates a composite structure by combining multiple graphene layers with controlled twist angles (0°-16° or 44°-60°) and interlayer covalent bonding. This composite approach leverages the outstanding mechanical properties of individual graphene layers while using covalent bonds to reinforce the interlayer connections, achieving both macroscopic thickness and high shear strength.
2Ease of manufacture
If conventional stacking methods are used to create multi-layer graphene, then the structure is simple to manufacture, but the interlayer bonding is uncontrollable and mechanically weak
Solution Approach 1:
The patent applies preliminary action by performing chemical functionalization (hydrogenation, fluorination, or other treatments) on the graphene layers before or during the stacking process. This pre-treatment prepares the graphene surfaces to form covalent bonds upon contact, ensuring strong and controllable interlayer bonding while maintaining a relatively simple manufacturing workflow.
Solution Approach 2:
The patent introduces control over critical parameters including twist angles (0°-16° or 44°-60°), chemical functionalization degree, and interlayer bonding density. By adjusting these parameters, the manufacturing process becomes controllable, enabling optimization of both mechanical strength and production feasibility for different application requirements.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly increases the shear strength of multi-layer graphene, enabling the production of ultrastrong, ultralight composite materials suitable for applications like ballistic protection and aerospace components.
Implementation Method 1
covalently bonding the first and second graphene layers, the bonding involving a fraction of carbon atoms of each of the first and second graphene layers
Implementation Method 2
Interlayer covalent bonding is accomplished by a chemical functionalization intermediate step, such as hydrogenation (e.g., in a hydrogen plasma)
Implementation Method 3
Interlayer covalent bonding is accomplished by a chemical functionalization intermediate step, such as fluorination (e.g., in a fluorine plasma)
Implementation Method 4
the weak van der Waals interlayer forces acting between consecutive graphene layers within the stack are responsible for the low shear strength of the stack
Data Source
AI summary
An article of manufacture includes a first graphene layer, a second graphene layer over the first graphene layer, the second graphene layer oriented at a first interlayer twist angle with respect to the first graphene layer and bonded by interlayer covalent bonds to the first graphene layer, and a third graphene layer over the second graphene layer, the third graphene layer oriented at a second interlayer twist angle with respect to the second graphene layer and bonded by interlayer covalent bonds to the second graphene layer. A multi-layer graphene article includes at least three graphene layers, each graphene layer being oriented at an interlayer twist angle with respect to an adjacent graphene layer and bonded by interlayer covalent bonds to the adjacent graphene layer.