A team of researchers at ETH Zurich has the perfect long-lasting solution to our fog problem. They have developed a very thin and gold-based transparent coating that can transform sunlight into heat, which can be applied to glass to prevent it from fogging.
The special coating is developed using titanium oxide(氧化钛) and gold particles. It selectively absorbs infrared(红外线的) radiations from the sunlight and creates a heating effect that is powerful enough to keep fog away from the surface of glass. The coating basically employs heat to stop fogging. The coating absorbs a large part of the infrared radiation, which causes it to heat up—by up to 8℃.
Previously, products like anti-fogging sprays create a very thin film of water on the surface to remove fog. The problem with such surfaces is pollution. Along with water, the sprays also soak up dirt, dust, oil, and various other dirty substances, and just a little dirt on the surface makes it useless. However, the new coating repels(排斥) water. Furthermore, the coating is significantly thinner, which makes it more transparent as well as flexible. It is heated passively and requires, during daytime, no additional energy source.
Gold might be expensive, but the researchers stress that their coating requires so little that the material costs remain low. Their coating is produced with standardized and readily scalable(可称量的) methods, all cost-effectively. However, although this product can work at very low levels of solar irradiation, it does rely on a certain amount of light.
The researchers will develop the coating further for other applications. In the process, they will examine whether other metals work just as well as gold. There is no need to fear, however, this would cause a car or a building to heat up more in the summer. The researchers have already filed a patent. Hopefully, this groundbreaking product will soon be available on the market.
