The way that materials are used in nature differ greatly to how we use them for our own technologies. We fabricate using smelts, powders and chemical solutions into exact designs, but nature on the other hand uses approximate design with growth by biological controlled self-assembly. Additive manufacturing (3D printing) does exhibit this strategy, but we need to consider the self-repairing, self-organisation, and hierarchical structures across all levels. Changes in structure and space are other key considerations.
Check out these interesting case studies below, or drop us a message if you are interested in collaborating on materials science R&D.
Male Morpho Butterflies are bright blue iridescent butterflies, whose colour has been reported to be so intense that they can be seen from low flying aircraft or “up to a quarter of a mile off” in their natural habitat in the rainforests of South America, as states P. Vukusic (1999).
The bright colour is not via pigments. Instead, the butterfly incorporates structural colour via corrugated ridges present on the scales of its wings. This is leading to developments in colour displays and the low-energy thermal imaging cameras.
BACTERIA INHIBITING MATERIAL
Shark Skin only experience minimal biofouling. The skin has denticles are arranged in a distinct diamond pattern with millions of tiny ribs at the nanoscale. The width-to-height ratio of shark denticle riblets corresponded to the mathematical model for the texture of a material that would discourage microorganisms from settling. This has new spawned the company Sharklet Technologies Inc. with applications ranging from healthcare to shipping.
SELF-REPAIRING AND STRONG MATERIALS
Nacre, which is also known as Mother of Pearl, is a naturally occurring composite formed from calcium carbonate and biopolymers that create a brickwork structure. It is also nearly a thousand times stronger than any of its component parts and a major target for biomimetic synthesis.
Design of the brickwork structure is central to developing nacre-like materials with enhanced properties. Gaoquan Shi, and colleagues, at Tsinghua University, began by making a hydrogel from graphene and a silk protein, called fibroin.
Solution casting and drying this hydrogel gave parallel graphene plates bound with fibroin that self-assembled to create a material with a brickwork structure.
The team’s material is an improvement over other composites owing to a number of different factors. Graphene is stronger than the inorganic platelets that are commonly used but Shi explained that the homogenous composite hydrogel ‘produced an ideal layered structure’ which amplified the mechanical properties. Coupled with the strong electrostatic and hydrogen bonding between fibroin and graphene, the system surpasses most composites previously reported.