Developed by scientists from Stanford University and the SLAC National Accelerator Laboratory, the powder is made up of nanoflakes of aluminum oxide, molybdenum sulfide, copper and iron oxide. All of these substances are readily available and inexpensive, plus only a small amount of the powder is required to treat a relatively large quantity of water.
Users start by stirring some of the powder into tainted water contained in a bottle or other transparent vessel, after which they leave it exposed to direct sunlight.
The molybdenum sulfide and copper absorb photons from the light, then act as a semiconductor/metal junction which allows the photons to release electrons. Those electrons are then free to react with the water, producing hydrogen peroxide and hydroxyl radicals which kill bacteria by rupturing their protective outer membranes.