The fabrication of 3D graphene folding nanomaterials with controllable thermal properties is the subject of new research available as a pre-proof in the journal Carbon.
Study: Functionalized graphene origami metamaterials with tunable thermal conductivity. Image Credit: Duet PandG/Shutterstock.com
For next-generation temperature control systems, graphene with adjustable thermal properties is critical.
Non-porous hybridized graphene folding meta-surfaces have a one-of-a-kind mixture of adjustable heat capacity, good strength, and improved durability. This is opposite to previously reported permeable graphene films that improve thermal conductance at the expense of mechanical features.
Importance of Graphene
Because of its exceptional thermal and mechanical characteristics, graphene, the basic one-atom dense two-dimensional (2D) substance, has sparked intense research interest.
Single-layer graphene has a wide range of mechanical properties.
Graphene's unusual features make it an attractive contender for foldable digital equipment, biosensors, metal-oxide-semiconductor devices, and nanoelectronics mechanisms. Its physical characteristics can be further tuned for application needs through fault engineering, mechanical loading, molecular crosslinking, and doping.
Thermal-tunability of Graphene
Tunability of thermal characteristics, increased durability, and high structural rigidity is required for various applications of graphene as radiative and temperature monitoring systems, automated, and adaptable nanodevices.
Defect construction, such as applying precise cutting techniques, creating gaps and holes, or producing 2D implemented nanomaterials, is one of the most effective ways for modifying the thermal properties of graphene, according to current computational and experimental research.
When flaws are introduced into graphene, photonic dispersion speeds up, softening phonon oscillations and lowering heat capacity.
At the same time, defect manipulation has an impact on graphene's mechanical features.
Graphene must exhibit a high degree of elastic modulus and ductility for numerous applications in flexible and wearable nanodevices. However, this improvement in elastic modulus comes at the expense of graphene's rigidity and toughness.
New design techniques should be created to integrate adjustable thermal characteristics with high strength and increased durability in graphene and nanostructures.
Foldable Graphene Origami Structures (GOSs)
Origami-based techniques might solve the characteristic thermal-mechanical trade-off in graphene.
A foldable one-atom-thick graphene sheet with folds produced by surface modification can be used to make complex folding graphene origami shapes.
Due to phonon dispersion in the crease area generated by surface modification, the creation of atomic bonds in the graphene sheet is predicted to reduce thermal conductivity.
The origami method may provide a design framework for building nano/microstructured modern tools with variable thermal expansion coefficients. Similarly, since no fractures or cavities are formed during the graphene origami synthesis, the rigidity of GOS may be maintained.
Molecular dynamics (MD) and finite element (FE) calculations were used to investigate the thermo-mechanical characteristics of GOS.
The graphene Miura-ori nanoparticles were initially produced and then folded by the researchers via surface modification.
The computational findings reveal that by adjusting the geometric properties and origami designs, changing the adatom kinds and densities, and applying mechanical stresses, the thermal properties of GOS may be adjusted.
Research Conclusion and Prospects
In conclusion, hybridized graphene nanoparticles are shown to offer a novel framework for building shape-changing graphene nanomaterials with adjustable thermal conductivity, as well as tailorable toughness, failure tension, and thermal expansion coefficient.
Surface functionalization is used to create the graphene origami metamaterial.
The atomic-level simulation findings reveal that by adjusting the bending width and design parameters, changing the hydrogenation concentration and adatom kinds, and applying mechanical stresses, a wide range of heat capacity may be achieved.
Externally applied stresses and architectural origami designs may be used to control the heat capacity of the constructed graphene origami nanostructures.
Thermal expansion indices of manufactured graphene origami nanostructures are negative.
Compared to previously published graphene nanomaterials, the bifunctional origami nanomaterials described here have two significant differences: first, the suggested graphene metasurfaces are fundamentally nonporous, retaining good strength while also increasing elastic properties when compared to pure graphene.
Second, pressure can be used to enhance heat capacity and decompression can be used to reduce it, demonstrating a viable technique for altering the heat capacity of tailored nanomaterials.
This research paves the way for the development of transportable graphene nanomaterials with switchable thermo-mechanical characteristics, which could be used in thermoelectric devices, nanosized temperature control structures, and adaptable nanoelectronics.
Cai. J., E. Estakhrianhaghighi., and A. Akbarzadeh (2022). Functionalized graphene origami metamaterials with tunable thermal conductivity. Carbon. Available at: https://www.sciencedirect.com/science/article/abs/pii/S0008622322000847