A group of Chinese researchers just defied the laws of physics by creating a material that promises to forever change the way we deal with global warming. Welcome to the future of passive cooling.
From the University of Sichuan they announce that they have developed an airgel composed of gelatin and DNA which achieved solar reflectivity greater than 100%. The result is seemingly impossible, but in practice?
The Science Behind 104%
Jian-Wen Ma, first author of the study (that I link to you here), explains the phenomenon:
The material has a reflectivity of 104% in the visible region, achieved thanks to the photoluminescence effect. The airgel's luminescence comes from the tightly cross-linked network of gelatin and DNA, which allows the chromophores to cluster together and inhibit nonradiative jumps in the system.
In simpler terms, theairgel it not only reflects sunlight, but also emits a small amount of its own light, thus exceeding 100% reflectivity and achieving a staggering 104%.
Features and benefits
This new material presents three really interesting peculiarities:
- Biodegradability: Airgel is completely biodegradable, offering an eco-friendly solution.
- Reparability and recyclability: The material can be repaired and recycled, further reducing its environmental impact.
- Cooling efficiency: It can lower the room temperature by 16 degrees Celsius even under high solar irradiation conditions.
Record-breaking passive cooling
Airgel, created by a process called “water welding“, has a multilayer structure that allows multiple reflections and dispersions of sunlight. The result? A noticeable improvement in solar reflectivity. A factor that could revolutionize various sectors.
In construction, it would give us building coatings that reduce cooling costs. In the automotive sector, coatings to improve the efficiency of car air conditioning. In agriculture, crop protection systems from external temperatures.
The importance of passive radiative cooling
Changyu Shen e Xianhu Liu, other researchers involved in a related commentary, point this out:
Passive radiative cooling stands out as an important innovation strategy for energy conservation efforts. It is crucial not to overlook the environmental implications of this approach
I agree: this new airgel represents a significant step towards more sustainable and efficient cooling solutions. The mix of exceptional solar reflectivity and biodegradability offers a truly promising response to the challenges of climate change.
In an increasingly warm world, the ability to create materials that exceed 100% solar reflectivity is a scientific triumph, but a tangible hope for a cooler, more sustainable future. As we eagerly await further developments and practical applications of this technology, we can be certain that the field of passive cooling will never be the same again.
