Researchers study a large-scale model of a sheet of graphene. (Clemson University Relations)

A wireless triboelectric nanogenerator (W-TENG) generates electricity from motion and vibrations. It consists of a biodegradeable polymer and graphene. When the two materials are brought together - through such actions as clapping the hands or tapping feet - they generate voltage.

The device generates a maximum of 3,000 volts - enough to power 25 standard electrical outlets, smart-tinted windows, or a liquid crystal display (LCD) monitor. Its electrical energy can be stored wirelessly in capacitors and batteries.