As global temperatures rise year by year and heatwaves become more common, surviving without air conditioning (AC) during hot weather has become increasingly difficult. However, due to power outages, the lack of AC units, or financial limitations, many people cannot afford or use air conditioning.
Chinese scientists have developed a unique sunscreen that not only protects the skin from harmful ultraviolet (UV) rays but also works like an air conditioner. This sunscreen lowers your body temperature, providing a cooling sensation instead of heat.
Researchers from Tsinghua University in Beijing have created this prototype sunscreen, which can reduce the body temperature by up to 6°C. With such a cooling effect, the need for air conditioning would be eliminated, making it easier to save on electricity.
A recent study showed promising results for this prototype sunscreen, especially as global summer temperatures continue to rise. This sunscreen would be particularly beneficial for individuals who spend long hours outdoors.
Being waterproof, the sunscreen stays on the skin for extended periods, reducing the feeling of heat while also protecting from UV rays. Radiative cooling technology is used to reflect or emit heat, cooling objects. This technology is also applied to unique materials such as coatings for buildings that keep them cool.
Titanium dioxide (TiO2), a white mineral known for its heat-reflecting properties, is an essential material in radiative cooling technologies. In this new research, TiO2 nanoparticles were used to create a sunscreen with the ability to block UV rays and offer radiative cooling features.
The study revealed that the TiO2 particles in the sunscreen reflect UV light and solar heat. It remains effective on the skin for up to 12 hours, without causing any itching. The sunscreen was tested in real-world hot and humid environments, and it was proven to provide a noticeable cooling effect.
When compared to conventional sunscreens, this new formulation cooled the skin by up to 6°C, a significant difference, particularly on hot days. The cost to produce 10 grams of this cream is only $0.92, the same as typical sunscreens available today.
While the exact timeline for when this sunscreen will be available to the general public remains unclear, the results of the research were published in the journal Nano Letters.
