Light-Activated Material Could Enable Heliotropic Solar Cells

Light-activated composite devices developed by Tufts University researchers were shown in testing to execute precise visible movements and form complex 3D shapes. The materials performed without wires or other actuating materials or energy sources. The design combines programmable photonic crystals with an elastomeric composite that the Tufts researchers engineered at the macro- and nanoscale to respond to illumination. The material is composed of two layers: a film with opal-like properties made of silk fibroin doped with gold nanoparticles (AuNPs) forming photonic crystals, and an underlying substrate of polydimethylsiloxane (PDMS), which is a silicon-based polymer. Photonic material in the shape of a flower can move in response...