Mass-produced nanotechnology-enhanced products hold great promise in the pursuit of sustainability. Nanotechnology is unfamiliar territory – such a (relatively) new area of science that it appears we’re still learning what we don’t know. How, for instance, can you assemble something that is orders of magnitude smaller than any available tools? We have not yet developed nanobots or nano-scale machines capable of manipulating materials effectively in any quantity. Moving particles around with electric or magnetic charges, for example, is not an easy thing to do, nor does it lend itself to mass production. It appears we won’t be able to produce nanomaterials in useful volumes for some time to come if we have to wait for nano-scale tools to be developed. Mass production is needed both to supply the needed quantities and to lower the cost so the technology is affordable. So where might this take us?
Self-assembly works, and is making the transition from the lab to the factory floor. Fortunately, molecules naturally attach together by attractive forces without external aid, and bond together like the parts in a jigsaw puzzle (link). Molecular chemists can design molecules that latch onto each other in specific ways and align themselves by surface tension-like forces. This idea of self-assembly, in which putting the appropriate molecules in close proximity to each other and in a medium in which natural attraction can pull them together in a desired way, is available now, and has great potential for production of the mass quantities of nano-materials that are needed. In fact, IBM started using self-assembly concepts in the production of computer chips in 2007 (link) (link), and a company called Nanotec now sells water and dirt-repellent coatings that self-assemble (link). A lithium ion battery is under development that uses self-assembling electrodes to achieve smaller size than its predecessors (link) (link). Could batteries be shipped in paint cans and “painted on” in self-assembling layers?
Self-assembling materials may soon make the transition out of the factory. While self-assembly is being implemented in factory conditions now, in the future it may be able to be implemented outside of controlled environments. This suggests that materials can be packaged in quantity, shipped to their point of application or use, and then either mixed or placed in conditions in which they will assemble themselves and acquire their desired capabilities. With self-assembling materials, the volumes of nano-substances we need can feasibly be produced, shipped, and applied where needed.
Self-assembling solar cell paints with built-in battery storage may be possible. IBM’s self-assembling nano-wiring combined with Nanotech-USA’s self-assembling coatings, the inkjet-printable solar cells (link) of Konaka Technologies (link), and MIT’s lithium ion nano-batteries makes me think of a solar cell paint with integrated battery storage. I am looking forward to having my house painted with photovoltaic paint – a paint that will self-assemble during the drying process into a light-catching photovoltaic coating that lasts a long time, has superior weather resistance and sealing characteristics, and has built in battery storage for excess energy. External electrodes would be attached before or after the paint is dry, and wiring would convey the electricity produced by the paint into the house where it can be used. The batteries would allow power to be drawn around the clock, and by the time the batteries have worn out, it will be time to repaint anyway. Of course, lithium being the toxic material it is, I hope that less toxic battery materials would be developed soon that would also self-assemble. Barring that, though, I could also live with recyclable batteries in the basement.
When my house is absorbing most or all available light, won’t it look black? Of course, when most of the incident light is trapped and turned into electricity by the black carbon nanotubes used, there won’t be much light to perceive as color, and I expect the solar cell paint will be black. Will we all someday be living in houses that appear black? I believe I could live with that – my house in the universally neat and formal, and in this case oh-so functional, “little black dress”, especially if it keeps my energy bills down. I just would hope I could get my wife to accept it.
As always, I welcome your comments.