A team of researchers from Stanford University and SLAC National Laboratory have developed a tiny device that can disinfect water in as fast as 20 minutes with the use of the sunlight. Measuring in at just 1 cm by 2 cm (0.4 in by 0.8 in) — about half the size of a postage stamp — the little purifier can harness a broad spectrum of the sun's rays to maximize its disinfecting ability.
The rectangular black device is made from a layer of copper and molybdenum disulfide, which under right conditions, create a disinfectant that kills microbes.
The team's findings, which are published in the journal Nature Nanotechnology, show that the tiny glass tablet killed 99.99% of bacteria in 25 mL of water with a bacterial concentration of 1,000,000 per mL in just 20 minutes.
So far, however, the device has only been proven to kill three types of bacteria and is not capable of removing chemical pollutants. The researchers still have to conduct more tests to determine if the device can decontaminate water with more types of microorganisms.