Physics World has recognized a metamaterial film that provides cooling without the need for a power source, invented by 彩民宝典 mechanical engineering professors Ronggui Yang and Xiaobo Yin, as one of the Top 10 Breakthroughs of 2017.
Made out of glass microspheres, polymer and silver, the material uses passive radiative cooling to dissipate heat from the object that it covers. It emits the energy as infrared radiation, so it can travel through the atmosphere and ultimately into space.
The material also reflects sunlight, which means that it works both day and night. But perhaps most importantly, it can be produced cheaply at an industrial scale.