Below the surface

Here’s my Crucible column for the May issue of Chemistry World. Arguably a bit parochial, but hopefully not without some resonance outside the UK. _________________________________________________________________________
According to the UK’s Engineering and Physical Sciences Research Council’s latest announcement in their “Shaping capability” initiative, surface science is to receive reduced funding in future. It’s a perplexing decision.

This is just one of the several controversial aspects of the directions that EPSRC is taking. But when you look at the topic-by-topic ratings made by the council (each is designated ‘maintain’, ‘grow’ or ‘reduce’), it is hard not to feel a little sympathy. Almost every subject is earmarked for receiving the current level of support, or more. Among the latter category are many well motivated choices, such as energy storage and photonics. Obviously not every subject can enjoy this privilege, and so hard decisions must be made. Whatever it ‘reduces’, the EPSRC is bound to incur criticism from those affected. The decision to reduce synthetic organic chemistry will surely also provoke dismay among RSC members. All the same, compromising surface science seems especially short-sighted given the apparent desire to focus on subjects that might boost economic growth.

It’s true that one of the most industrially important aspects of surface science – catalysis – is covered by a separate category that will not suffer the same fate. But there’s plenty more to the subject that deserves strong support. As Peter Knight, president of the Institute of Physics, has said in response to the announcement, “surface science is an area of interdisciplinary research, often the most fertile source of new scientific breakthroughs”.

The EPSRC argues that it doesn’t regard the importance of surface science as having declined, but rather, that it is becoming assimilated into other topics. The funding cut is intended to accelerate this transition: the EPSRC seems to be proposing that the previous system is no longer the best way to allocate funds for surface science. Or to put it another way, the topic has become a victim of its own success in making itself so pervasive

The council says that “we would expect future surface science research to make significant contributions to other disciplines and key societal challenges”, and identifies nanotechnology and microelectronic device engineering among these. Some surface scientists have already suggested that ‘rebadging’ into such areas will rescue them.

But can applications like these be severed from the wellspring of basic science that makes them possible? Take the development of scanning probe microscopes in the 1980s, pioneered at IBM’s laboratories in Zurich. These tools, now fundamental to nanoscience and biophysics (for example), were devised purely as a means of high-resolution surface imaging, although their potential for nanoscale manipulation of matter, probing surface forces, and exploring quantum phenomena quickly became apparent. IBM has emphasized these fundamental aspects of the methodology ever since, most recently by demonstrating that charge distributions of single molecules can be imaged directly (Mohn, F., Gross, L., Moll, N. & Meyer, G. Nature Nanotechnol. online publication doi:10.1038/nnano.2012.20.) – an advance that could conceivably offer new insights into chemical bond formation.

This is just one example of how the development of new techniques in surface science is rarely problem-specific. Whether it is low-energy electron diffraction, surface-enhanced Raman spectroscopy, scanning optical microscopy or countless other methods, these techniques are hungrily adopted by many different fields. In fairness, the EPSRC says that a priority for surface science “in the reduced environment is the development of novel and sophisticated new tools and techniques for the study of surfaces”. But how can that objective avoid seeming diminished by its ‘reduced environment’?

And furthermore, can the core of surface science really be just methodological? I doubt it. The conceptual foundations, laid down by the likes of J. D. van der Waals and Irving Langmuir, lie with notions of surface free energy, intermolecular forces, adsorption, wetting and two-dimensional phases that are of undiminished relevance today, whether one is talking about chemical vapour deposition or biomolecular hydration. There is an intellectual unity to the discipline that transcends its rich variety of techniques.

This raises an almost philosophical question of whether or not a discipline can exist and perhaps even thrive when largely divorced from an over-arching label. At the very least, it’s a gamble. But what seems most alarming is the message that this sends out at a time when the study of surfaces and interfaces is looking ever more vital to so many areas of science and technology. The days when surface science meant looking at single molecular phases on perfect crystal faces in high vacuum are disappearing. Now we are starting to get to grips with interfaces in all their scary – as Wolfgang Pauli saw it, diabolical – complexity. Real surface processes are often dominated by impurities and mixed phases, by inhomogeneous solvation, by roughness, curvature, charge accumulation, defects. Understanding these things will tell us important things about cell and molecular biology, corrosion, atmospheric aerosols and cloud microphysics, nanoelectronics, biomaterials and much more.

That seems to be understood elsewhere. A new initiative for ‘solvation science’ in Germany, for example, recognizes the cross-cutting features of studying interfaces. And despite excelling in this area, the UK lacks a dedicated surface-science body like the Surface Science Society of Japan. Such considerations suggest that it would be more opportune to be strengthening foundations rather than chipping away at them.