Elastocaloric Effect in Graphene Kirigami

Abstract

Kirigami, a traditional Japanese art of paper cutting, has recently been explored for its elastocaloric effect (ECE) in kirigami-based materials (KMs), where an applied strain induces temperature changes. Importantly, the feasibility of a nanoscale graphene kirigami monolayer was experimentally demonstrated. Here, we investigate the ECE in GK representing the thinnest possible KM to better understand this phenomenon. Through molecular dynamics simulations, we analyze the temperature change and coefficient of performance (COP) of GK. Our findings reveal that while GKs lack the intricate temperature changes observed in macroscopic KMs, they exhibit a substantial temperature change of approximately 9.32 K (23 times higher than that of macroscopic KMs, which is about 0.4 K) for heating and −3.50 K for cooling. Furthermore, they demonstrate reasonable COP values of approximately 1.57 and 0.62, respectively. It is noteworthy that the one-atom-thick graphene configuration prevents the occurrence of the complex temperature distribution observed in macroscopic KMs.

Enhanced Elastocaloric Effects in γ-Graphyne

“…This behavior is consistent with the observations made by Lisenkov et al, 20 Cantuario and Fonseca, 23 Li et al, 69 and Silva and Fonseca 24 for the eC of carbon nanotubes and graphene. However, this behavior is the opposite of that observed in rubber 68 and kirigami graphene, 25 where the eC temperature change is positive when stretched and negative when the strain is released.…”

“…A similar method was applied to unveil eC behaviors in graphene kirigami. 25 Utilizing different protocols, Zhao, Guo, and Zhang 26 and Cai, Yang, and Akbarzadeh 27 predicted significant COP in 3D graphene architectures and graphene origami, respectively. However, to our knowledge, the eC effect in graphyne-based structures remains to be fully explored.…”

“…While computational studies on the eC effect in nanomaterials are still in their early stages, noteworthy findings have already been obtained. − Lisenkov et al pioneered molecular dynamics-based predictions for eC effects in graphene and carbon nanotubes. Similarly, Zhang explored eC effects in boron-nitride nanotubes, and Patel and Kumar predicted the eC effect in zinc-oxide nanowires.…”

Origami Metamaterials Enable Low-Stress-Driven Giant Elastocaloric Effect

“…Due to the high Debye temperature for graphene (2100–2300 K), the quantum correction to the classic specific heat in MD simulations is necessary to obtain reliable estimates for eC effect. We introduce such corrections empirically through rescaling the adiabatic temperature change obtained from classical computational simulations by a factor of C MD / C Q ( T ) ,, normalΔ T normalM = ( C M D / C Q false( T false) ) normalΔ T normalM normalD where Δ T M and Δ Τ ΜD denote the modified adiabatic temperature change and the adiabatic temperature change obtained from MD simulation, respectively. C MD and C Q ( T ) are the computational and quantum corrected values of the specific heat, respectively.…”

Reduction of Interlayer Interaction in Multilayer Stacking Graphene with Carbon Nanotube Insertion: Insights from Experiment and Simulation

“…This can describe the deformation of Gr and CNT and the resulting energy variation. The AIREBO potential is selected because it is widely used in the mechanical behavior of Gr and CNT with reasonable precision and efficiency and can be easily implemented in LAMMPS for quick results. ,− Note that recently developed machine learning-based interatomic potentials , could offer a promising alternative with proper validation in Gr and CNT systems. However, we consider the treatment of classical potential sufficient for the current simulations since no bond-breaking of C atoms that critically requires density functional theory accuracy is involved.…”