For all of us dreaming of climbing skyscrapers or take an upside-down nap from the ceiling, science is now catching up with Hollywood.
(Credit: Matthijs Rouw)
Researchers are mimicking the adhesive properties of gecko feet to develop materials sticky enough to keep a full-size superhero from plummeting to the ground. Gecko toes have millions of hair-like structures, setae, acting together as an excellent adhesive. Each seta is divided into hundreds of small branches, all of which interefere with the molecular structure of the surface the gecko is climbing on. The setae sticks to the surface due to van der Waals forces, which is the weak attraction molecules have for each other when they are brought very close together. How well the gecko sticks to a surface is dependent on the number of setae touching it and also on the roughness of the surface. Lucky enough, a 50 cm long gecko have about 6.5 million setae, creating enough force to support the weight of two people!
In 2007, the Italian physicist Nicola Pugno calculated that a Spiderman suit of carbon nanotubes and structured to mimick gecko feet could in fact be adhesive enough to cling a person safely to a wall or ceiling. However, there are still challenges.In addition to being very adhesive, the suit must be made of a material that is releasable as hanging from the ceiling is less fun if you are unable to climb down again. The material should also be self-cleaning, since dust and dirt could make the suit less sticky and leave you in risk of losing your grip..Tag(s) : Nanoscience, Science, Spiderman, Gecko, Nano,