A team from Vanderbilt University is developing an ultra-thin device that can generate electricity from motions as subtle as sitting down, opening up the possibility of clothes that charge phones or light up like an LCD screen.
Different materials are designed to tap into the different types of energy we waste in our day-to-day movements. There are fabrics that generate a charge through friction, thermoelectric devices that harvest body heat, and piezoelectric systems that work on mechanical stress. The Vanderbilt team's device falls into the latter category.
The system is made with tiny layers of black phosphorus, each just a few atoms thick. When the material is bent or squeezed it produces a small electric charge, and its thinness means it can do so from even the smallest movements a person might make in their daily activities.