Letters from Nano-land

What academic journals should one read to get the latest news about nanotechnology research? This isn’t as an easy a question to answer as one might think, and this difficulty reflects the fact that nanoscience and nanotechnology have still not really gelled into a coherent scientific culture. So nanotechnology done by physicists will often end up in physics journals (Physical Review Letters being the most prestigious), while that done by chemists will similarly end up in chemistry journals. The nearest thing we have to specialised nanotechnology journals are the general materials science journals like Nature Materials and Advanced Materials, both of which are essential reading. A recent addition to this space, though, is explictly pitching to be the nanotechnology journal of choice – this is the American Chemical Society’s journal Nano Letters. This is winning a lot of friends in the nanoscience community; the time between papers being submitted and them appearing is very short, which appeals to impatient authors, and the editorial board is a list of some of the most distinguished nanoscientists anywhere. And the impact factor – a crucial measure of where a journal is in the scientific pecking order, defined by the average number papers appearing in the journal are cited by other papers – is high. Nature Materials is still at the top of the pile (not counting Nature and Science, of course), with an impact factor of 13.53, but Nano Letters, at 8.45, has already shaded ahead of Advanced Materials, at 8.08. The long-established Institute of Physics journal Nanotechnology trails a long way behind at 3.32. Journals, and their editorial policies, are important in defining emerging fields, so it’s interesting to take a snapshot of how the Nano Letters editors see the field, on the basis of the papers published in the current edition.

Carbon nanotubes are clearly still objects of nanofascination, accounting for five out of the twenty five papers in the issue. It’s largely the electronic properties of the nanotubes that excite, rather than their mechanical properties, and this theme of nanoelectronics is continued with another five papers on semiconductor nanowires. Soft nanotechnology and bio-nanotechnology is an important theme, accounting for eleven papers. There’s some overlap; a couple of papers use the self-assembling properties of biological molecules like DNA and peptides to guide the assembly of inorganic nanotubes and nanowires. Experiment dominates over theory, with only three purely theoretical papers. Most of the papers are quite a long way from any applications. The work that’s closest to market includes a paper on the use of quantum dots for magnetic resonance imaging, one on using titanium dioxide nanoparticles for solar generation of hydrogen. At the other end of the scale, there’s one paper on the use of the scanning tunneling microscope to mechanically position and react individual molecules on a surface.

It’s interesting to ask where, geographically, the papers comes from. As one would expect from a USA-based journal, the largest contribution comes from the USA, with 56% of the papers. Europe accounts for 36%, with a fair spread of countries represented, while the remainder come from Canada. Interestingly, this issue contains no contributions at all from the far east. In fact, over the whole of 2005 only 2% of the papers in Nano Letters came from China.

I’m not entirely sure what all this means, but one thing that strikes me is there’s relatively little relationship between this (small) sample of what the academic nano- community thinks is exciting work, and what is currently being commercialised by industry. An optimist would take this as a sign that there was a significant pipeline of work that will be coming ready to commercialise maybe 5-10 years from now.