By this point, we have discovered a slew of natural, incidental, and artificial nanomaterials with a wide variety of properties and capabilities. Particularly prominent are graphene and borophene — i.e., one-atom-thick layers of graphite and boron, respectively — which have been widely hyped in recent years.
Graphene, discovered only in 2004, has alternately been labelled “the most remarkable substance ever discovered” and a substance that “could change the course of human civilization.” Not to be outdone, borophene, first synthesized in 2015, has been dubbed “the new wonder material,” as it is stronger and more flexible than even graphene.
Certainly there is a place for both in a wide variety of areas (not the least of which are areas like electronics and robotics), but the full extent of their capabilities is still being explored. And certainly their versatility has set them apart from other nanomaterials, like nanoenzymes, which have found particular application in the medical field (specifically, in tasks like bioimaging and tumor diagnosis), or the membranes that are used for water purification.
Yet, these nanomaterials (and many others) have yet to reach their full potential.
What factors determine the effectiveness of a nanomaterial for human use? What makes a truly great nanomaterial? The answer largely comes down to the material’s capability, functionality, and scalability.
Capability
How important a nanomaterial’s capabilities actually are depends on how it can be applied, and seeing as how the range of applications for various materials is endlessly vast, you could very well say that any nanomaterial is more than capable of fulfilling some kind of function. But ultimately, utilizing that many nanomaterials is more cumbersome and inefficient than anything — meaning that by discovering and utilizing a few nanomaterials with strong and multifaceted capabilities, we can more rapidly make advancements and create new nanotech.
The most produced nanomaterials to date are carbon nanotubes, titanium dioxide, silicon dioxide and aluminum oxide, and are great examples of varied capability. Carbon nanotubes are most often used in synthetics. Titanium dioxide is used for paints and coatings, as well as cosmetics and personal care products. Silicon dioxide is used as a food supplement, and aluminum oxide is used in various industries.
The distinction for these four nanomaterials is that while their use is widespread, their capabilities pale in comparison to other materials. For instance, graphene and borophene have much greater potential in not only the aforementioned fields but also medicine, optics, energy, and more. Graphene and borophene truly demonstrate what a great nanomaterial’s capabilities should look like.
Functionality
It’s one thing to have the capability for greatness, but it’s another thing to be able to carry it out. This is where nanomaterials are put to the test, to see if they can integrate well into our technology and products in order to improve them. In most cases, nanotech and other advancements won’t be comprised solely of the specific nanomaterial, meaning that making sure it functions properly alongside other materials and in composite forms is essential.
This is where nanomaterials begin to have trade-offs. Titanium dioxide, zinc oxide and silicon dioxide are all utilized effectively and with ease, with very few issues related to function. However, stronger materials tend to have more unstable qualities: borophene in particular is susceptible to oxidation, meaning that the nanomaterial itself needs to be protected, making it difficult to handle. Graphene lacks a band gap, making it impossible to utilize its conductivity in electronics without some way to control it. Without overcoming such hurdles for implementation and functionality, these powerful nanomaterials will remain at arm’s length of greatness.
Scalability
Even once a nanomaterial is able to make the cut and perform well, the final hurdle they must pass is scalability and mass production. After all, part of the appeal of these technological advancements would be its widespread use. While nanomaterials like titanium dioxide, zinc oxide, and silicon dioxide have had no issue with production and subsequent use, their issues lie elsewhere.
There were long-standing questions about the scalability of graphene — particularly the costs involved — but there is now greater optimism on that front. A 2019 study predicted, in fact, that worldwide graphene sales would reach $4.8 billion by 2030, with a compound annual growth rate of 45 percent.
Borophene has likewise faced scalability issues, though in the case of that nanomaterial it has centered more on the production of mass quantities. (It was judged as a major breakthrough, for example, when Yale scientists produced a mere 100 square micrometers of the substance in 2018. Efforts continue on that front, however, and much was learned from scaling up graphene. So it would appear to be only a matter of time.
If and when scalability is achieved, it seems safe to say that the full potential of both nanomaterials can be explored. We know they are versatile, but at that point, we will truly find out how versatile they can be.