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Atomic Force Microscopy Cantilever-Based Nanoindentation: Mechanical Property Measurements at the Nanoscale in Air and Fluid
Published on: December 2, 2022
Shear modulus property characterization of nanorods
Chengming Jiang1, Wenqiang Lu, Jinhui Song
1Department of Metallurgical and Materials Engineering, Center for Materials for Information Technology (MINT), University of Alabama, Tuscaloosa, Alabama 35487, USA.
Nano Letters
|December 5, 2012
Summary
We developed a new atomic force microscopy (AFM) method to directly measure the shear modulus of nanorods. This technique precisely quantifies the mechanical properties of individual nanostructures.
Area of Science:
- Materials Science
- Nanotechnology
- Mechanical Engineering
Background:
- Characterizing the mechanical properties of nanomaterials is crucial for their application.
- Direct measurement of the shear modulus in individual nanorods presents significant challenges.
Purpose of the Study:
- To introduce an innovative atomic force microscopy (AFM)-based technique for direct shear modulus measurement of individual nanorods.
- To validate the method by measuring the shear modulus of a ZnO nanorod.
Main Methods:
- Utilizing microfabrication to position a nanorod along a trench edge on a silicon substrate.
- Employing AFM in contact mode to scan the nanorod, inducing torsion via tip force and confinement.
- Retrieving shear deformation and force from AFM topography and lateral force images, respectively.
Main Results:
- Successfully measured the shear modulus of a ZnO nanorod (radius 166 nm, length 4 μm) to be 8.1 ± 1.9 GPa.
- Demonstrated the feasibility of the technique for nanorods with polygon cross-sections.
Conclusions:
- The developed AFM technique offers a direct and reliable method for characterizing nanorod shear modulus.
- This approach has broad applicability for evaluating the mechanical properties of various nanowires and nanorods.
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