Biomimetic Nanocomposites

Today’s materials have to be multifunctional, adaptable, and resource conscious.  These materials qualities are essential for multiple technological bottlenecks and represent the characteristics of organic-inorganic composites.  Nature can be a source of inspiration about composite design enabling multifunctionality, adaptability, and energy efficiency. The implementation of Nature-inspired designs requires, however, new manufacturing approaches.  Layer-by-layer assembly (LBL/LbL) is the technique that affords scalable engineering of nanocomposites with nanometer precision and rare versatility.   Mechanical and other properties are also remarkable exceeding those of comparable materials often by orders of magnitude.  The reasons behind these properties is LBL’s exquisite control over the interfaces between dissimilar components and their self-assembly dynamics.   These capabilities represents the central advantage of this technique and mirrors the engineering principles and sometimes the actual processes of materials synthesis in living cells. 

One example of conceptual biological material is nacre known for high toughness and iridescence.  LBL allowed nacre replicas to be made from a variety of components that eventually surpassed and expanded the mechanical and optical properties of the natural prototype. Retaining the same structural design, we view these layered composites as a platform for multidimensional design of materials properties: toughness, stiffness, strength, transparency, conductivity; ion transport, polarization rotation, and biological response. In the ongoing projects, we address the following questions:

How to replicate other quintessential biomaterials, for instance, teeth enamel or cartilage using man-made nanocomponents?

How to impart new properties to bioinspired composites characteristic of inorganic nanomaterials not used in Nature, for instance plasmonic and excitonic states?

Energy and biomedical applications are in the center of our translational work with biomimetic composites.  A new type of nanoscale “building blocks’ being used in LBL for these technological areas are aramid nanofibers.  Besides high strength, they impart nanocomposites with high strength, temperature resilience, and high ion conductivity needed for charge storage devices.  Layered nanocomposites from aramid nanofibers result in solid-state ion conductors that prevent lithium batteries fires.   Ongoing translational studies also involve reconfigurable kirigami nanocomposites for optical devices for biosimilar machine vision sensitive to circularly polarization.