Exploring the mechanical properties of nanometer-thick elastic films through micro-drop impinging on large-area suspended graphene
Journal
Nanoscale
Journal Volume
14
Journal Issue
1
Pages
42-48
Date Issued
2022
Author(s)
Abstract
In this work, the dependence of effective Young's modulus on the thickness of suspended graphene was confirmed through a drop impingement method. Large area suspended graphene (LSG) layers with a diameter of up to 400 μm and a nanometer thickness were prepared through transferring chemical vapor deposition grown graphene from copper substrates. 4, 8, and 12-layer LSG samples were found to be crumpled yet defect-free. The mechanical properties of LSG were first studied by observing its interaction with impinging droplets from an ink-jet nozzle. First, the effective Young's modulus was calculated by fitting the instant deformation captured by high speed photography within microseconds. Next, droplets deposited on LSG caused deformation and generated wrinkles and the effective Young's modulus was calculated from the number of wrinkles. The above methods yielded effective Young's modulus values ranging from 0.3 to 3.4 TPa. The results from these methods all indicated that the effective Young's modulus increases with the decreasing thickness or size of suspended graphene layers. Moreover, the crumpled LSG yields higher effective Young's modulus than ideal flat graphene. These comprehensive results from complementary methodologies with precise LSG thickness control down to the nanometer scale provide good evidence to resolve the debate on the thickness dependence of mechanical strength for LSG. ? The Royal Society of Chemistry.
Subjects
Chemical vapor deposition
Deformation
Elastic moduli
Graphene
High speed photography
Chemical vapour deposition
Copper substrates
Defect-free
Effective young's modulus
Elastic films
Graphene layers
Highspeed photography
Microdrops
Nanometer thickness
Suspended graphene
Drops
Type
journal article