The blackest of black was invented by scientists at the Massachusetts Institute of Technology in 2019. This color is so incredibly dark that it can absorb 99.9% of all visible light, surpassing even the well-known Vantablack, a deep black that caused a stir in the art world.
Simply put, if you were to apply this lackluster color to a spoon, it would create a black hole-like effect in the center of your kitchen. In the long run, this remarkable color has the potential to improve technologies such as telescopes, cameras, and even next-generation iPhones that require light-blocking capabilities.
If the blackest black is the darkest color, what would occur if we had its exact opposite?
In fact, last year, in an effort to answer that very question, a team of scientists from Purdue University developed the whitest white. This color had the ability to reflect an astounding 98.1% of light, earning the team a place in the Guinness Book of World Records. However, unlike Vantablack, successful application of paint made with this shade necessitated a minor alteration — the paint needed to be made thinner.
Sure thing.
The group responsible for creating the whitest paint in the world has altered its chemical composition to make it less viscous. This modification has made the paint suitable for application on an array of surfaces, including cars, planes, trains, and even T-shirts. By coating these items with the innovative paint, they will reflect a large amount of sunlight, subsequently minimizing the requirement for air conditioning.
In a statement, Xiulin Ruan, a mechanical engineering professor at Purdue University who authored the study, said that this not only results in cost savings but also diminishes energy consumption, thereby decreasing greenhouse gas emissions. He added that compared to other cooling methods, this type of paint releases all heat into outer space, leading to the direct cooling of the planet. It is remarkable that a mere paint can achieve all of these benefits.
Their new formula has been outlined in detail in a paper published on Monday in the journal Cell Reports Physical Science, which you can access for more information. Ruan shared that he has been approached by various entities, ranging from spacecraft manufacturers to architects and companies producing clothing and footwear. The common inquiries he receives are regarding where they can purchase it and if it can be made thinner.
To be precise, it is not available for commercial purchase currently. However, Ruan mentioned that the team is presently working towards finding a way to make it available.
The piece of art called “The Redemption of Vanity” is created by Diemut Strebe, who is an artist-in-residence at MIT. A yellow gem is placed on the left side, while the same gem is coated with the blackest black substance on the right side. Take another look, it is definitely there.
Diemut Strebe
Adding Color to the World as a Shield
At some stage in our lives, we pick up a degree of scientific awareness concerning fashion. “Avoid wearing black in hot weather and favor white to reflect sunlight.” At times, it may appear to be an excuse devised to persuade children to wear pristine, white clothing instead of their grubby Batman t-shirt, which they’ve sported for the umpteenth time.
However, this fact is accurate. The color black has a higher tendency to absorb light and the heat that comes with it, while white reflects both. This is precisely why Ruan’s innovative paint is effective. The researchers utilized a nanoporous material, which consisted of hexagonal boron nitride as the pigment, a substance that is commonly found in lubricants, in order to produce their latest version of the world’s whitest paint. A mere 150-micron (0.15 millimeter) thin layer of this substance was sufficient to achieve a solar reflectance rate of 97.9%.
“The strong scattering of sunlight is caused by the high refractive index of hexagonal boron nitride,” stated Andrea Felicelli, an author of the study and a Ph.D. student in mechanical engineering at Purdue University. Felicelli added, “The unique morphology of the material’s particles, called nanoplatelets, was also found to be important based on our team’s models. The hexagonal shape of these nanoplatelets was essential for their enhanced ability in reflecting back solar radiation, making them a more effective alternative to the spherical nanoparticles commonly used in other cooling paints.”
The latest composition of the striking paint stands in stark contrast to the team’s prior formula, which relied on barium sulfate, an economical and white crystal-like powder recognized for its capacity to reflect light. The previous version demanded an application thickness of 400 microns (0.4 millimeters) to attain the intended reflective effect, a considerably bulky layer for a paint application.
Ruan explained, “While thick paint may be suitable for painting sturdy static structures such as building roofs, it is not ideal for applications that require specific sizing and weight limitations. Thinner and lighter paint is necessary in such cases.” This is exemplified, for instance, when aiming to reduce air conditioning utilization in vehicles or lowering power consumption in apartments by utilizing a newly coated wardrobe with hexagonal boron nitride.
On the left, you can observe the team’s past version of white paint, while on the right, the updated one is visible. Additionally, the team included “air voids” in their list of paint ingredients to make the mixture extremely porous on a very small scale. According to them, this reduced density, along with the thinness, made the new paint 80% lighter than the barium sulfate variant.
“In a statement, George Chiu, a mechanical engineering professor at Purdue and the author of the study explained that by painting the exterior of an airplane, it will require less energy to cool the interior on hot summer days. This translates to significant energy savings. Additionally, for spacecrafts, every ounce of weight counts, and this paint can contribute to reducing their weight.”
