In case you missed it, Elon Musk called BS on the field of nanotechnology last week. The ensuing Twitter spat was admittedly rather small on the grand scale of things.

But it did throw up an important question: just what is nanotech, and where does the BS end and the science begin?

I have a sneaky suspicion that Musk was trolling with his initial nano-comment. After all, much of the tech in his cars, solar cells and rockets relies on nanoscale science and engineering. But having worked in nanoscale science for nearly 30 years, I must confess that my BS monitor also gets a little twitchy sometimes around talk of nanotechnology.

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The ‘next industrial revolution’

Mainstream nanotechnology came of age around 20 years ago, as the United States government began cross-agency efforts to invest in what it initially tagged as “the next industrial revolution”.

Scientists at the time were excited by how they might exploit some of the more unusual properties of materials that emerge when they are precisely designed and constructed at a really small scale, such as abrupt changes in electronic behaviour, or the emergence of super-strong structures. And because it’s always easier to sell an idea to funders and policymakers if you have a clear brand and a compelling message, the term “nanotechnology” became the rallying call for this new “industrial revolution”.

To keep things simple, early definitions of nanotechnology focused on exploiting the “novel properties” that some materials begin to exhibit when they’re engineered at a scale of between 1 – 100 nanometres (a nanometre is one billionth of a metre). These days, definitions tend to be more fluid. But there are still widespread assumptions among nano-researchers that there’s something utterly different about the nanoscale. And this is where my BS monitor gets a little uneasy.

Without a doubt, the rallying cry of nanotechnology has transformed science and engineering over the past two decades. It has stimulated vast amounts of research and development investment; it has led to new ideas and breakthroughs, often involving interdisciplinary research; and it has enthused and inspired a whole new generation of scientists and engineers.

But no science suggests there is something generically unique and special about the size range between 1 nanometer and 100 nanometers. And this is where brand-nano risks becoming unstuck from scientific reality.

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Marketing science

The trouble is, the way nanotechnology was initially pitched fudged the science to sell the idea. It spun a tale of small scales and unique properties that most experts at the time realised was more marketing than science. Yet they went along with it because of the promise of funding.

Almost overnight, material scientists became nanotechnologists; as did colloidal chemists, heterogeneous catalyst experts, electron microscopists, molecular biologists; even toxicologists. Suddenly the work that scientists and engineers had been doing for decades was rebranded as spanking new nanotechnology; much to the consternation of engineers like Eric Drexler, who popularised a very different view of nanotechnology in the 1980’s, and was subsequently marginalised by the new nano gold rush.

With this history, it’s not surprising that nano is sometimes called out as BS. Yet this is not the end of the story, because underneath the hype and the spin, there is some truly amazing science and engineering that occurs at this small scale. And this begins to make much more sense when we ditch “brand-nano” and start talking about nanoscale science and engineering.

Working at the nanoscale

Nanoscale science has its roots in the early 1900s, as scientists began to develop instruments and theories that illuminated how the nanoscale positioning of atoms in materials affects their properties. From the 1930s, techniques like electron microscopy and X-ray diffraction allowed scientists to begin mapping out the nanoscale structure of materials. And from around this time they began to intentionally manufacture and exploit the properties of nanoscale particles (engineered nanoparticles of silicon dioxide for instance were available from the 1940s as Aerosil®).

Through the 1970s and 80s, the burgeoning field of materials science continued to transform our understanding of how to design and engineer materials to make them stronger, lighter, more chemically reactive, and more conducting. Semiconductors, integrated circuits and microprocessors emerged from this wave of innovation, including giant magnetoresistance – the technology behind massive capacity hard disk drives.

It’s this trend in science, technology and engineering that was rebranded and relaunched as nanotechnology in the 1990s. It wasn’t the dawn of a new industrial revolution. Neither was it the emergence of a new technology. Rather, it was a rebranding of work researchers had been labouring over for decades.

And yet, for all my cynicism, brand-nano did bring about something special: it broke down the barriers between previously stove-piped disciplines, and stimulated a new wave of interdisciplinary research in a way that has led to some incredible advances that range from cheap DNA sequencing and novel cancer treatments, to high efficiency solar cells and revolution in battery technologies.

Challenging assumptions

Now, nanotechnology is embedded in mainstream science and technology, and a new generation of nanotechnologists are passionately breaking new nano-ground. Many of these are amazing scientists, who are doing incredible work.

Yet it worries me that some of the history of how we got here has been lost as brand-nano has become institutionalised. And because of this, it’s not necessarily a bad thing that, once in a while, its underlying nano-assumptions are challenged.

At the end of the day, not everything that’s done in the name of nano is special, unique, or interesting. And scientifically, there’s nothing particularly special about that bright line between the worlds below and above 100 nanometres.

Despite this though, the more we learn to understand, design and engineer the world around us from the atoms it’s made of upward, the better we’ll get at creating technologies that improve our lives.

This is the true power of nanoscale science and engineering. And trust me, that’s not BS.