There is a tremendous interest in mimicry of multifunctional biomaterials such as the gecko feet, lotus leaf, arthropod eye, and butterfly wing. Our objective is to build on our understanding of wetting, capillarity, and particles at interfaces to develop hierarchical and multifunctional bio-inspired materials.
a.) Droplet-based hierarchical bio-inspired materials
There is a tremendous interest in mimicry of multifunctional biomaterials such as the gecko feet, lotus leaf, arthropod eye, and butterfly wing. Our objective is to build on our understanding of wetting, capillarity, and particles at interfaces to develop hierarchical and multifunctional bio-inspired materials. For example, the compound eye found in most arthropods consists of a curved array of individual microlenses decorated with nanoscale protuberances (ommatidium), and is a source of inspiration for its optical and surface properties. The structure is also a challenge to reproduce synthetically, making it a good target for the development of novel fabrication methods. We introduced a liquid manufacturing process based on the assembly of liquid droplets and particles at fluid interfaces to naturally introduce the necessary curvature and deformability that alleviate fabrication challenges of compound lenses.
- D. Shin, T. Huang, D. Neibloom, M. A. Bevan, and J. Frechette, “Multifunctional liquid marble compound lenses”, ACS Applied Materials & Interfaces, 11 34478-34486, 2019. 10.1021/acsami.9b12738
b.) Mechanism behind frog adhesion under flooded conditions
Our ongoing effort to understand how surface structure influences lubrication forces is motivated by the locomotion of the tree frogs. Central to the adhesion and locomotion of tree frogs are their structured toe pads, which consist of an array of interconnected channels that end in mucus secreting glands. We aim to better understand how surface structure modulate contact formation and lubrication in wet and flooded environments.
- B. Ryu, R.J. Hommel, P. Roberts, and J. Frechette, “Promoting rotation, friction, and mixed lubrication for particles rolling on microstructured surfaces”, Physical Review E, 99, 022802 2019. 10.1103/PhysRevE.99.022802
- B. Ryu, C. Dhong, and J. Frechette, “Rolling spheres on bio-inspired surfaces”, Langmuir, 33, 164-175, 2017. 10.1021/acs.langmuir.6b04153
- G. Pilkington, R. Gupta, and J. Frechette, “Scaling of the dynamic Boundary Conditions for Microstructured Surfaces in the Thin Channel Limit”, Langmuir,32, 11341-11352, 2016. 10.1021/acs.langmuir.5b04134.
- C. Dhong and J. Frechette, “Coupled effects of applied load and surface structure on the viscous forces during peeling”, Soft Matter, 11, 1901-1910, 2015. 10.1039/C4SM02616K
- R. Gupta and J. Frechette, “Measurement and scaling of hydrodynamic interactions in the presence of draining channels”, Langmuir, 28, 14703-14712, 2012. 10.1021/la303508x