It’s been 10 years since Vantablack claimed the title of “blackest black”, astounding the world with its ability to darken materials beyond recognition.

This proprietary coating completely obscures an object’s surface features, causing it to appear like a dark, 2D void. But over the past decade, coatings have gotten even darker.

And Vantablack is no longer the world’s blackest black. Scientists have unlocked new techniques for producing increasingly absorptive materials, mostly by accident. And good news for goths everywhere: you might be able to buy some  of this stuff yourself one day. [ INTRO MUSIC ] In the search for “blackest black”, there are two things to consider: what do we mean by black, and how do we measure it?

Black is generally considered the absence of colored light. Humans perceive color when our brains interpret signals from our eyes, where tiny receptors go “ping” when they’re hit by light with the correct wavelengths. So if an object is neither emitting nor reflecting enough of that visible light, our receptors don’t get triggered, and we perceive the thing as black.

But visible light isn’t all there is. To an infrared camera, I am positively glowing right now. So from a broader physics perspective, black is defined as the absence of reflection at any wavelength.

And the lower a material’s reflectance, the blacker it is. However, you can pick and choose how you measure that reflectance, and get different results. Because one, even materials that look black aren’t equally reflective… or should I say non-reflective… at every single wavelength.

And two, your material might be better or worse at reflecting a beam of light depending on the angle the light is hitting it. So if you were gunning for a record for blackest black, you could go for the lowest reflectance that only appears at a specific angle and for a specific wavelength of light. But you’d probably have a beef with a research team that developed a material with a lower overall reflectance.

So scientists usually measure reflectance as the total light scattered in any direction. A reflectance of 100% means your material is the whitest white, and 0% is the blackest black. The terms aren’t official, but super blacks tend to be materials with a reflectance of less than 0.5%, which is about 10 times less reflective than your blackest paints.

Meanwhile, ultrablacks are less than 0.05%. But what’s happening to the 99.95%? Well, that light gets absorbed by the molecules in the material, and converted into a different kind of energy.

And eventually, the molecules emit that energy as heat. That’s why dark colors feel so warm after spending time in direct light. All that absorption is why you’ve got everyone from astronomers to… whatever you call the people who are trying to improve solar panel efficiency… pursuing the blackest blacks.

If you can find something to paint the inside of your telescope, you can help wrangle any errant light rays from scattering around and messing up your astronomical observations. Or, if you find something that stops a solar cell bouncing a bunch of sunlight back into the atmosphere, you can maximize the amount of energy your solar panels can convert into electricity. But before there were super-black materials, there were… normal black materials.

Humans have used black pigments to create art for at least 12,000 years. One example is charcoal, which is still popular in art  classrooms across the world. Charcoal is made through a process called carbonization, where organic material0 is burned using very little oxygen, so that the big and complex carbon-based molecules break down and leave mostly pure carbon.

The purer the carbon in your final product, the darker your charcoal is. That’s because it’s the carbon that’s responsible for charcoal… as well as other black pigments… being black. Thanks to its atomic structure, carbon absorbs light across a wide range of wavelengths.

So if you have a really pure charcoal sample, you can get a reflectance less than 10% across the visible light spectrum. But carbon isn’t the only compound capable of absorbing light. Humans used other pigments in art, such as squid ink, and that mostly gets its color from complex molecules called melanin.

You might remember that melanins are responsible for color pigmentation across the animal kingdom, including humans! Then, starting in the 19th century, chemists discovered they could design pigment molecules. Colors like cadmium red, cobalt blue, and chromium green are named after the ingredients whose structure makes them reflect certain wavelengths of light.

These discoveries eventually led to a black paint with  reflectance of less than 3%. And if you’re looking to create your own goth paradise, you can actually buy cans of the stuff. But for a while, that was the best we could do.

Pigments could only get so dark. To get even less reflective, we needed some help from physics. Thanks for watching this SciShow video!

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It’s not just an object’s chemical makeup that dictates how much light it absorbs, and therefore how black it is. Structure can, too. But for a long time, it was super tricky to create  the super small structures you’d need to make blacks even blacker.

Then, in 2002 a brand new record was set: a material that reflected less than 0.5% of visible light wavelengths. And researchers achieved this by chemically eroding the surface, creating microscopic, light absorbing craters. It was a huge leap in the  search for the blackest black. but unfortunately, the method d idn’t work very well at infrared wavelengths.

And for many practical purposes, these light-absorbing materials  should be great at that, too. Then, in the 2010s, a brand  new technique hit the scene. And it really seemed to knock  all the previous records out of the park.

Now, a little warning here: the materials we’re talking about from now on are so black that your screen can’t even express how black they are. So you’ll have to trust us a bit when we tell you that these materials are really stunningly black. Enter Vantablack, which claimed the world  record for “blackest black” at the time. “VANTA” is actually an acronym for  “vertically aligned nanotube array”.

And by nanotube, they mean carbon nanotubes. Because VACNTA doesn’t really roll off the tongue By the time Vantablack rolled around, academic labs and government research facilities like NASA had already been working on this kind of technology for a couple years. Here’s how it works: these super  black coatings are created by growing   forests of carbon nanotubes.

And carbon  nanotubes are very appropriately named,   because they’re nano-scale tubes of pure carbon. Each of these “trees” are  millionths of a meter tall,   and billionths of a meter wide. And  together, a nanotube forest can trap   light and bounce it around the trees  until it’s absorbed by the carbon atoms.

In other words, carbon nanotube  forests are a perfect combination   of the carbon-based black pigments  and the structure-based absorption   properties that scientists could  achieve through chemical etching. So super black VANTA coatings consistently reflect   less than 0.5% of light across  visible and infrared wavelengths! Before Vantablack came on the scene, several  labs had demonstrated near-perfect absorption:   less than 0.1% in the visible  and near-infrared bands!

But in 2014, Vantablack coined the catchiest  name, and thereby got all the hype. As for the world record, well, the  company’s research is closely guarded. The level of black was supposedly  “independently verified”, but not publicly peer-reviewed. if you go by those numbers, the original Vantablack had reflectances as low as 0.05%, at least for visible light.

And the record-breaking contest has only accelerated since then. In 2015, a team created a super efficient light-absorber by suspending some funny-shaped nano-scale gold particles in water. Using the same principle as the carbon nanotube forests, these gold particles use their shape to bounce light between one another until its energy is totally dissipated.

When you look at the numbers, the reflectance isn’t quite as impressive as Vantablack: less than 2% of light across both  visible and infrared wavelengths. But the gold particles are more reliable across a range of wavelengths than Vantablack was. And they require far less material than carbon nanotubes in order to absorb the same amount of light.

Together, that was good enough for the Guinness Book of World Records to dub these gold nanoparticles as the new “blackest black”. Then in 2016, Vantablack beat the record with, wait for it, Vantablack2. With this new iteration, they clarified that across a  broad spectrum of wavelengths… and viewed from all angles… Vantablack2 always reflects less than 1% of light.

But Vantablack isn’t the current record holder. And today’s blackest black was discovered by accident. In 2019, researchers were trying to boost the electrical conductance of aluminum.

And it turns out the ability to move electrons around is closely related to  the ability to absorb light. So the team wound up discovering a coating process that reflects less than 0.01% of visible and infrared light from all angles. It even reflected less than 0.005% of certain wavelengths, making this new material not  just super, but ultra black.

The authors of this study think this could be due to a combination of factors, but mostly how they microscopically etched the surface of the aluminum before growing the nanotube forest on it. This new ultrablack coating made a big statement when an artist collaborated with the researchers to cover a 2 million dollar diamond. The piece was named “The Redemption of Vanity”, and displayed at the New York Stock Exchange.

Now, so far, all these carbon  nanotube-based coatings share a common weakness. They might be shock and vibration-resistant… that makes them suitable for use on, say, the inside of a telescope that has to get to space via rocket. But those tiny lil nanotubes are delicate, and easily destroyed by touch!

And this is the real reason we can’t deck ourselves out in Vantablack merch. The carbon nanotube forests can only be grown on specific kinds of surfaces, and those tiny trees just aren’t fit for everyday wear and tear. But in 2023, a new record was set for an ultrablack touchproof material.

It boasts a reflectance of less than 0.02%. The researchers managed this by making a surface with micro-cavities, similar to the super black etching from 2002. Then, they cast a mold of the micro-cavities, and stamp the mold onto a polymer sheet.

That polymer can maintain that stamped structure when you touch it… I mean, assuming you’re not, like, mushing your thumb down on it trying to break it. Meaning ultrablack materials might finally be making their way into commercial, daily use. This is proof that carbon nanotubes don’t have to be the future of really black materials.

In fact, in 2024, researchers accidentally made a super-black material out of wood! They were originally attempting to make wood more waterproof. But they found that their plasma etching technique gave samples of basswood a light-absorbing texture reminiscent of the carbon nanotube forests.

They could also take advantage of lignins, the light-absorbing compounds naturally found in wood. Altogether, their samples reflected  about 0.7% of visible light. And the plasma etched wood still looked black when the team coated it with gold, to improve the material’s electrical conductance.

The team has dreams of deploying their super-black wood to consumers, at least in the form of watches or jewelry. But there’s another way scientists might gift us some of the  blackest blacks possible: by turning to nature itself for inspiration. That’s right, researchers have been studying ultra-black animals!

Because it turns out, some species of spiders, birds, and deep-sea fish have evolved super light-absorbing coloring with reflectances as low as 0.05%. And the exact technique varies from creature to creature. But generally, their ultra-black appearances are thanks to a mixture of melanin pigments and micro-scale structures.

While humans have managed to create blacker blacks than anything we’ve found in the animal kingdom, 0 .05% is right in line with the original Vantablack. And nature managed to do that just with evolution. Across many different biomes!

And a lot earlier than our human-grown records were established!! I guess that gives scientists a lot to reflect on when it comes to making the blackest black. [ OUTRO ]