Gecko-inspired combined lamellar and nanofibrillar array for adhesion on nonplanar surface

Area of Science:

• Materials Science
• Nanotechnology
• Surface Engineering

Background:

• High-aspect ratio nanofiber arrays are crucial for various applications.
• Adhesion and mechanical stability of nanofiber arrays on diverse surfaces remain challenging.
• Existing support structures often lack the compliance needed for nonplanar applications.

Purpose of the Study:

• To fabricate and characterize novel lamellar support structures for nanofiber arrays.
• To investigate the adhesion and mechanical properties of nanofiber arrays on these lamellar supports.
• To evaluate the performance of the combined system on both planar and nonplanar surfaces.

Main Methods:

• Fabrication of lamellar structures from a hard polymer.
• Experimental characterization of nanofiber arrays supported by lamellae.
• Measurement of shear strength and compliance on planar and nonplanar substrates (e.g., gratings).

Main Results:

• Lamellar structures effectively support high-aspect ratio nanofiber arrays.
• Nanofiber arrays on lamellae show 5x greater shear strength on a 100 µm peak-to-peak grating compared to unsupported arrays.
• The lamellar support significantly enhances compliance, achieving 160x higher values than arrays on flat backing layers, attributed to compliant lamellar flaps.

Conclusions:

• Polymer-based lamellar structures provide a robust and compliant platform for nanofiber arrays.
• This innovation improves the adhesion and adaptability of nanofiber arrays to complex surfaces.
• The developed system holds potential for applications requiring flexible and strong nanofiber interfaces.