Richard Jones – Page 46 – Soft Machines, by Richard Jones

Printing silicon

The main driving force for developing plastic electronics – the use of semiconducting polymers to make logic devices, light emitting diodes and displays, and solar cells – is the hope that these materials can be processed very cheaply. Because these materials are soluble, devices can be made by processes like ink-jet printing or screen printing. Compared to standard silicon-based electronics, the performance of these devices is often not very good, but the fact that you won’t need the massive capital expenditure of a conventional silicon fab tilts the economics towards the plastic materials, at least for applications where cost is more important than performance. But Nature this week reports an interesting twist – a group from the Seiko-Epson labs in Japan report a new way of printing silicon directly from solution (see also the Epson press release here).

The method is based on using polysilane as a precursor material. Polysilane is essentially the silicon based analogue of the well-known polymer polyethylene, consisting of a long chain of silicon atoms, each of which has two hydrogen atoms attached. But unlike polyethylene, polysilane is both unstable and very difficult to work with, being insoluble in most common solvents. The Japanese group got over this problem by starting with a five-membered ring version of the polysilane molecule – cyclo-pentasilane (this is the silicon analogue of cyclopentane). They found that polysilane was soluble in solutions of this precursor, and these solutions could be ink-jet printed and converted into pure silicon layers by a simple heating step.

The silicon layers formed this way are amorphous, not crystalline, and their electronic properties are not very good compared to silicon films prepared by more conventional routes (though they are better than most polymer semiconductors). Plastic electronics still has some advantages over this new process, which requires temperatures too high for the use of plastic substrates. The printing step is also complicated by the need to exclude water and oxygen. Nonetheless, it’s an important step forward towards the development of low-cost electronics for applications like large area displays and cheap solar cells.

Some reflections on UK nanotechnology policy

The think-tank Demos today released a report, Governing at the Nanoscale: People, policies and emerging technologies. I was one of the speakers at the launch event in London. This, more or less, is what I said.

It’s a pleasure to be asked to give my reactions to “Governing at the Nanoscale”, the latest of a very interesting set of pamphlets from Demos about the relationship between science and society. I’m responding as a scientist who participated in the public engagement aspects of the project, so I’d like to make some personal comments about the experience of public engagement from the scientist’s point of view. Then I’ll go on to make some more general comments about the way UK policy in this area has developed.

As you have seen from the film of the project, I had a lively time at the “Nanoscientists meet nanopublics” event held in the autumn. I’m struck by the editing of the film, which makes it clear that engaging with the public doesn’t necessarily mean agreeing with them! But scientists can derive a great deal from this sort of event, which prompt them to develop a richer picture of the relationships between the science they do themselves and the wider field that they work in with society and the economy.

For me, this event wasn’t an isolated one – it was one of some 21 public engagement events of one kind or another that I’ve taken part in in person over the last couple of years. I mention this not just to blow my own trumpet, but to emphasise the time taken up by a serious attempt to become involved in public engagement work. The rewards of this kind of effort are very great, but to be realistic one also needs to recognise the considerable disincentives that the way science is organised in the UK places in the way of this kind of activity.

Institutionally, public engagement brings no reward at all to the scientists who participate in it. University scientists working in physics, chemistry and materials science departments live and work in an atmosphere of insecurity – the financial pressures on these departments is very great and the threat to their future is very real, as we see in the recent machinations over the closure of Sussex’s chemistry department – the former home, of course, of Britain’s most famous Nanotechnology Nobel Laureate, Sir Harry Kroto. In this atmosphere, academic scientists need to focus on two things – directly raising contract and grant money to keep their departments afloat financially, and putting out high impact academic publications, to ensure a high grade in the Research Assessment Exercise, on which the very survival of departments depends. Public engagement is good for the discipline as a whole, but a Head of Department advising a young scientist is likely to urge him or her to concentrate on getting grants and writing papers for the RAE. Recent policy developments – the advent of full economic costing and the possibility of the RAE being replaced by a metrics-driven system – will only exacerbate this problem. If policy makers want scientists to engage with the public, something needs to be done about these systematic structural disincentives.

I’d like to move on to the more general question of the way policy has evolved in this sphere in connection with nanotechnology. To be blunt, the story here is of an opportunity presented to the UK to take a world lead, an opportunity that has been allowed to trickle away.

The Royal Society/ Royal Academy of Engineering report, published in the summer of 2004, was widely welcomed both in the UK and abroad. It made some very definite recommendations; here I’ll concentrate on three issues. On the possibility of the toxicity of some nanoparticles, the report recommended the setting up and funding of a centre for nanotoxicology studies. Similarly, on issues surrounding the more general relationships between nanotechnology and society, the report recommended funding a centre. Finally, the report recommended a well funded and coordinated program of public engagement. I think many of us were profoundly disappointed by the government’s response to this report, published in spring of last year, which simply rejected the first two of these recommendations.

Let me take the nanotoxicity issue first, as this is proving a case study in how to make a relatively small and manageable problem much bigger than necessary. “Is it safe?’ is the first question that the public, journalists or anyone asks about new products and new processes. It’s not a profound problem, but it needs an evidence base to answer. The report published by the Nanotechnology Research Coordination Group last autumn was in many ways a very good document, with a very good overview of the knowledge gaps and the research needed to fill them. The problem was that it simply failed to provide a mechanism to fill those gaps, simply hoping that good proposals would come to the research councils for funding by peer review. This seems to me to be a category error – the science we need to underpin regulation isn’t necessarily good science as defined by peer review, and if the capacity to do the research isn’t there one can’t just expect it to appear spontaneously.

On the broader relationships between nanotechnology and society, the story is similarly depressing. In the presence of so many excellent social scientists, I’ll not rehearse all the arguments for why these kinds of studies are a good idea, but I would like to pick up two important aspects. We’ll come to public engagement in a moment, but one thing my experience so far tells me is that debates about the impact of nanotechnology need to be informed by clear thinking about plausible possible futures, thinking that needs to be underpinned both by accurate science and an understanding of society and economics that goes beyond the naiveity displayed by a lot of futurism. The second point I’d make is that currently government is spending very large sums of money in an attempt to realise economic gains from its science investment. This spending is informed by tacit or explicit models of innovation, but are these models being critically tested? As we see focused and well resourced centres being set up to study these issues in the USA and in the rest of the Europe, in the UK we have a handful of excellent but small-scale projects, but no centre, no ear-marked funding, no coordination.

Public engagement is perhaps the one area where the picture is not so bleak, and in which the UK has taken a lead. A number of significant efforts, some government funded through schemes like Sciencewise, some, like Nanojury UK, initiatives from outside government, have been carried out. The government’s draft public engagement strategy – published last summer – sets out an overall framework, and a body – the Nanotechnology Engagement Group (which I chair) – has been charged with coordinating and disseminating good practise across government departments and agencies. The challenge now is designing institutional structures so that policy making really is informed by all this public engagement activity. In the key spending organisations – the research councils, led by EPSRC, in what used until recently to be the Innovation Directorate of the DTI, and in the MNT program, I don’t yet see those institutional structures in place.

In EPSRC, there are promising developments in the shape of the new committee chaired by Lord Winston set up to advise Council on public engagement issues. But, in the sphere of nanotechnology, the problem is that there isn’t actually a nanotechnology program for insights from public engagement to shape. The strategy of EPSRC with respect to nanotechnology has been, in essence, not to have a strategy. Has this worked? There are real concerns that the UK is not doing well in nanoscience and nanotechnology. A pair of international studies, commissioned by EPSRC, tell a depressing story. Most recently, we’ve had the report “International Perceptions of UK Research in Physics and Astronomy 2005”, which said “One particular area still requiring attention is nanoscience – it has become a very large area of emphasis worldwide, yet the UK lacks coherence and international visibility in the field.” A similar review for chemistry a few years ago told a similar story: “Nanoscience and technology in the UK clearly lags…It is, however, an area that requires seamless integration of electrical engineering, applied physics, chemistry, and mechanical engineering, and access to specialised facilities: it thus represents the type of multicentre, multidiscipline research at which the UK is constitutively weak. “ Recognising this weakness, EPSRC has set up a working party to consider a new strategy, which will report his autumn, but I’m left with the worry that there is a real structural problem emerging here.

Another point of view might be that what’s important here is that we succeed in making money from nanotechnology, and these societal and public engagement issues are just a distraction from this economic imperative. Clearly the government takes the innovation agenda extremely very seriously, but I would argue that it is a very serious mistake to suppose that the innovation agenda can be isolated from these societal issues. The most obvious connection is, of course, that the public that we’re engaging with is the very same public that will be the customers for the nano-enabled products we’re hoping for, and if they don’t buy the products then no-one will make any money. We hear frequent references to the sorry saga of agricultural biotechnology. A less obvious connection is stressed by my colleague Stephen Wood. It is also the public, working in the many economic sectors that will be affected by nanotechnology, all the way from directly science-based industries to all the areas in which the products of nanotechnology might be put into use, who will, by embracing or failing to embrace nano-enabled products and processes in their working practises, determine their economic impact. In any case I’d prefer to put the issue in a positive way – in our system, societal needs and desires are delivered through market mechanisms, so achieving consensus on what society wants from nanotechnology will as a by-product lead to the desired economic gains.

It’s worth taking a look at the history of the UK’s programme for promoting the commercialisation of nanotechnology. Again, this features a report with strong recommendations that were not followed. The 2002 Taylor report advised the immediate establishment of at least two National Nanotechnology Fabrication Centres. The government instead chose to implement a distributed, network, approach – the Micro- and Nano- Technology Initiative. Is this working? It’s probably too early to judge the economic impact directly, but again we can look at the perceptions of those from abroad. In September 2005 The US based consultancy LUX research published “Ranking the Nations: Nanotech’s Shifting Global Leaders.” This ranked the UK 12th out of 14th by measures of “Technology Development Strength”, not just behind Japan, the USA and South Korea, but behind France, Australia and Russia, and leading only India and China. One can argue, of course, about the validity and robustness of these measures, but these perceptions have a way of becoming self-fulfilling prophecies, as inward investment decisions are made on the basis of this kind of reports.

I’ve deliberately widened my discussion beyond public engagement and societal issues, because I think there is a depressing pattern emerging – a pattern of lack of commitment, institutional fragmentation, and a tendency to diffuse and unfocused efforts, which gives rise to the perception from outside the UK of a fundamental lack of seriousness.

One might ask why this matters. My answer isn’t so much that I believe that nanotechnology will soon be a one trillion dollar industry or will revolutionise this or that aspect of society. What’s more important is that nanotechnology is a test case for a new kind of science, fundamentally interdisciplinary, motivated by applications. How do we arrange to do goal-oriented science that delivers societal needs via market mechanisms with the broad support and consent of the population? This to me is the central question that underlies “Governing at the Nanoscale”.

The Nottingham nanotechnology debate – transcript now available

Last summer, a debate was held at Nottingham in which proponents and sceptics of the Drexlerian vision of molecular nanotechnology exchanged views (with me in the latter camp). I think it was notable both for its constructive tone, and for the high quality of the debate, helped by the presence of many very distinguished UK nanoscientists in the audience. At the time it was promised that a film of the event and a transcript would be published. These things often take longer than expected to come to fruition, but Philip Moriarty now reports, via a comment here, that the transcript, published in the journal Nanotechnology Perceptions, is now available for download from the Nottingham Nanoscience Group’s webpages. Since the links themselves are a bit obscure, the PDF of the transcript is here, and a short introductory piece by Philip is here.

To quote Philip Moriarty’s words: “The transcript on the following pages is the first time that a public (and lengthy) debate on the feasibility of nanomachines and molecular manufacturing, involving a significant number of world-leading surface- and nano-scientists, has been published in its entirety in the scientific literature.”

Which nation’s scientific output is rising fastest?

China, you might say, but you’d be wrong, according to a study of world rankings in science published recently by the UK government (latest DTI study into the outputs and outcomes from UK science – 920 kB PDF). This looks at a variety of input and output measures to construct a fairly complete picture of the distribution of scientific activity and impact around the world. Notwithstanding the surprising answer to my trick question (revealed at the end of this post), this report confirms the rapid growth of China as scientific power, the lessening of the formerly unchallenged dominance of the USA, and (from a parochial perspective) the rather strong performance of the UK, which spends less on research and has fewer researchers than its competitors, but nonetheless in comparison produces proportionately more science with a greater impact.

It’s in spending on science research that the rise of China is most obvious – in real terms (adjusted for purchasing power parity) China’s research spend has increased four-fold in the last decade; it now exceeds that of all other individual countries except USA and Japan, and has reached half the European Union total. In terms of output of scientific publications, China now has a 5% world share, up by a factor of three in the last decade, and now greater than France. Again, in terms of individual nations the USA still leads by this output measure, with almost exactly one third of world output, but the European Union nations taken together have now outstripped the USA, with 37.9% of publications. The UK, at just less than 9%, is the second placed individual nation, having recently overtaken Japan. If we took the Asia-Pacific group of China, Korea, Taiwan and Singapore together they would account for 10% of world output.

What about quality and impact? Here the USA still has a clear lead; taking as a measure of world impact the share of the most highly cited papers (taken as the top 1% in each discipline) puts the USA in the lead with 61%, while the UK outperforms its volume share with 13% of highly cited papers. China still underperforms on this measure but the gap is closing, and is likely to close further as citation counts are a lagging indicator – it takes some years for spending on science to translate, first into publication outputs, and only later into citations of those papers by other workers.

The country whose output of scientific publications has increased the most over the last decade is Iran, whose output has increased by a factor of ten, albeit from a low base (China’s increased by a factor of three, the second fastest rate of growth). It will be interesting to see, in the light of recent political developments, whether Iran’s good performance will continue.

The best of both worlds – organic semiconductors in inorganic nanostructures

Today’s picture is a scanning electron micrograph of a hybrid structure in which organic light emitters are confined in a micropillar by a pair of inorganic multilayer mirrors. These hybrid organic/inorganic structures have interesting photonic properties that may have applications in quantum cryptography and quantum computing; this work comes from my colleagues in the physics department here at Sheffield in collaboration with some of our electrical engineers.

SEM image of a micropillar
Image by Wen-Chang Hung, image post-treatment by Andy Eccleston.

This structure is made by laying down, by chemical vapour deposition, 12 pairs of alternate layers of silicon oxide and silicon nitride, each exactly one quarter of a light wavelength in thickness. This is coated by a 240 nm (half a wavelength) thick layer of the polymer polystyrene, doped with an organic dye called Lumogen red, which in turn is coated by another 12 pairs of layers, this time of tellurium oxide and lithium fluoride, thermally evaporated. The pillar is carved out of the resulting layer cake structure by using a focused ion beam.

The multilayers act as perfect mirrors. Imagine putting a light source in between two parallel mirrors – you’d get an infinite (if the mirrors are perfect) series of reflections of the light. In our situation the dye molecule is the light source; when it emits a single photon, that photon is going to interfere with its ghostly counterparts emitted from the reflections, which are all in phase with each other. This makes it a very efficient producer of single photons – potentially these could be used for quantum cryptography or quantum computing.

All of this has already been demonstrated using quantum dots – tiny particles of inorganic semiconductor – as the light emitter. What’s the advantage of using an organic dye instead? In these devices, photons are emitted when an electron and a hole annihilate. These electron-hole pairs – called excitons – are very weakly bound in ordinary semiconductors, which means that these devices only work at rather low temperatures, about 50 K. In organic molecules the charges distort the structure of the molecule itself, which means that the exciton is bound much more strongly and the device will work at room temperature. It goes without saying that this feature makes the possibility of an economically viable quantum computer seem much closer. To be fair, though, the organic materials have disadvantages, too – they are susceptible to being bleached by bright light.

The work is a collaboration between my colleagues in physics, Ali Adawi, Ashley Cadby, Daniele Sanvitto, Liam Connolly and Richard Dean, who are postdocs and grad students in the groups of David Lidzey, Mark Fox, and Maurice Skolnick. Device fabrication was done with the help of Wen-Chang Hung and Abbes Tahraoui, in Tony Cullis’s group in our Electronic and Electrical Engineering Department. It’s reported in the current edition of Advanced Materials here (subscription required).

The road to nanomedicine may not always be quick or easy

Of the six volunteers who became seriously ill during a drug trial last week, four, mercifully, seem to be beginning to recover, while two are still critical, according to the most recent BBC news story. It’s still too early to be sure what went so tragically wrong; there are informative articles, with some informed comment, on the websites both of New Scientist and Nature. What we should learn from this is that even as medicine gets more sophisticated and molecularly specific, many things can go wrong in the introduction of new therapies. The length of time it takes new treatments to get regulatory approval can be frustratingly, agonisingly long, but we need to be very careful about the calls we sometimes hear to speed these processes up. The delays are not just gratuitous red tape.

The drug behind this news story was developed by a small, German company, TeGenero immunotherapeutics. It’s a monoclonal antibody, code-named TGN1412; a protein molecule which specifically binds to a receptor molecule on T-cells, a type of white blood cell which is central to the body’s immune response. The binding site – code-named CD28 – is a glyco-protein – a combination of a protein with a carbohydrate segment – which provides the signal to activate the T-cells. What’s special about TGN1412 is that the action of this drug alone is sufficient to activate the T-cells; normally simultaneous binding to two different receptors is required. It’s as if TGN1412 overrides the safety catch, allowing the T-cells to be activated by a single trigger. It’s these activated T-cells that then carry out the therapeutic purpose, killing cancer cells, for example.

Few people have connected these events with bionanotechnology (an exception is the science journalist Niels Boeing in this piece on the German Technology Review blog). There are now a number of monoclonal antibody based drugs in clinical use, and they are not normally considered to be the product of nanomedicine. But they do illustrate some of the strategies that underlie developments in nanomedicine – they are exquisitely targeted to particular cells, they exploit the chemical communication strategies that cells use, and they increasingly co-opt biology’s own mechanisms for clinical purposes. Biology is so complex that it’s always going to spring surprises, and the worry must be that as our interventions in complex biological systems become more targeted, so the potential for unpleasant surprises may increase. Whenever one hears blithe assurances that nanotechnology will soon cure cancer or arrest ageing if only those bureaucratic regulators would allow it, one needs to think of those two men struggling for their lives in a North London hospital. There may be good reasons why the pace of innovation in medicine can sometimes be slow.

How much should we worry about bionanotechnology?

We should be very worried indeed about bionanotechnology, according to Alan Goldstein, a biomaterials scientist from Alfred University, who has written a long article called I Nanobot on this theme in the online magazine Salon.com. According to this article, we are stumbling into creating a new form of life, which is, naturally, out of our control. “And Prometheus has returned. His new screen name is nanobiotechnology.” I think that some very serious ethical issues will be raised by bionanotechnology and synthetic biology as they develop. But this article is not a good start to the discussion; when you cut through Goldstein’s overwrought and overheated writing, quite a lot of what he says is just wrong.

Goldstein makes a few interesting and worthwhile points. Life isn’t just about information, you have to have metabolism too. A virus isn’t truly alive, because it consists only of information – it has to borrow a metabolism from the host it parasitises to reproduce. And our familiarity with one form of life – our form, based on DNA for information storage, proteins for metabolic function, and RNA to intercede between information and metabolism – means that we’re too unimaginative about conceiving entirely alien types of life. But the examples he gives of potentially novel, man-made forms of life reveal some very deep misconceptions about how life itself, at its most abstract, works.

I don’t think Goldstein really understands the distinction between equilibrium self-assembly, by which lipid molecules form vesicles, for example, and the fundamentally out-of-equilibrium character of the self-organisation characteristic of living things. I am literally not the same person I was when I was twenty; living organisms are constantly turning over the molecules they are made from; the patterns persist, but the molecules that make up the pattern are constantly changing. So his notion that if we make an anti-cancer drug delivery device with an antibody that targets a certain molecule on a cell wall, then that device will stay stuck there through the lifetime of the organism, and if it finds its way to a germ cell it will be passed down from generation to generation like a retrovirus, is completely implausible. The molecule that it’s stuck to will soon be turned over, the device itself will be similarly transient. It’s because the device lacks a way to store the information that would be needed to continually regenerate itself that it can’t be considered in any sensible way living.

If rogue, powered vesicles lodging in our sperm and egg cells aren’t scary enough, Goldstein next invokes the possibility of the meddling with the spark of life itself – electricity. But the moment we close that nano-switch and allow electron current to flow between living and nonliving matter, we open the nano-door to new forms of living chemistry — shattering the “carbon barrier.” This is, without doubt, the most momentous scientific development since the invention of nuclear weapons.” This sounds serious, but it seems to be founded on a misconception of how biology uses electricity. Our cells burn sugar, Goldstein says, which “yields high-energy electrons that are the anima of the living state. “ Again, this is highly misleading. The energy currency of biology isn’t electricity, it’s chemistry – specifically it’s the energy containing molecule ATP. And when electrical signals are transmitted, through our nerves, or to make our heart work, it isn’t electrons that are moving, it’s ions. Goldstein makes a big deal out of the idea of a Biomolecule-to-Material interface between a nanofabricated pacemaker and the biological pacemaker cells of the heart. “A nanofabricated pacemaker with a true BTM interface will feed electrons from an implanted nanoscale device directly into electron-conducting biomolecules that are naturally embedded in the membrane of the pacemaker cells. There will be no noise across this type of interface. Electrons will only flow if the living and nonliving materials are hard-wired together. In this sense, the system can be said to have functional self-awareness: Each side of the BTM interface has an operational knowledge of the other.” This sounds like a profound and disturbing blurring of the line between the artificial and the biological. The only trouble is, it’s based on a simple error. Pacemaker cells don’t have electron-conducting biomolecules embedded in their membranes; the membrane potentials are set up and relaxed by the flow of ions through ion channels. There can be no direct interface of the kind that Goldstein describes. Of course, we can and do make artificial interfaces between organisms and artefacts – the artificial pacemakers that Goldstein mentions are one example, and cochlear implants are another. The increasing use of this kind of interface between artefacts and human beings does already raise ethical and philosophical issues, but discussion of these isn’t helped by this kind of mysticism built on misconception.

In an attempt to find an abstract definition of life, Goldstein revives a hoary old error about the relationship between the second law of thermodynamics and life: “The second law of thermodynamics tells us that all natural systems move spontaneously toward maximum entropy. By literally assembling itself from thin air, biological life appears to be the lone exception to this law. “ As I spent several lectures explaining to my first year physics students last semester, what the second law of thermodynamics says is that isolated systems tend to maximum entropy. Systems that can exchange energy with their surroundings are bound only by the weaker constraint that as they change, the total entropy of the universe must not decrease. If a lake freezes, the entropy of the water decreases, but as the ice forms it expels heat which raises the entropy of its surroundings by at least as much as its own entropy decreases. Biology is no different, trading local decreases of entropy for global increases. Goldstein does at least concede this point, noting that “geodes are not alive”, but he then goes on to say that “nanomachines could even be designed to use self-assembly to replicate”. This statement, at least, is half-true; self-assembly is one of the most important design principles used by biology and it’s increasingly being exploited in nanotechnology too. But self-assembly is not, in itself, biology – it’s a tool used by biology. A system that is organised purely by equilibrium self-assembly is moving towards thermodynamic equilibrium, and things that are at equilibrium are dead.

The problem at the heart of this article is that in insisting that life is not about DNA, but metabolism, Goldstein has thrown the baby out with the bathwater. Life isn’t just about information, but it needs information in order to be able to replicate, and most centrally, it needs some way of storing information in order to evolve. It’s true that that information could be carried in other vehicles than DNA, and it need not necessarily be encoded by a sequence of monomers in a macromolecule. I believe that it might in principle be possible in the future to build an artificial system that does fulfill some general definition of life. I agree that this would constitute a dramatic scientific development that would have far-reaching implications that should be discussed well in advance. But I don’t think it’s doing anyone a service to overstate the significance of the developments in nanobiotechnology that we are seeing at the moment, and I think that scientists commenting on these issues do have some obligation to maintain some standards of scientific accuracy.

Taking the high road to large scale solar power

In principle there’s more than enough sunlight falling on the earth to meet all our energy needs in a sustainable way, but the prospects for large scale solar energy are dimmed by a dilemma. We have very efficient solar cells made from conventional semiconductors, but they are too expensive and difficult to manufacture in very large areas to make a big dent in our energy needs. On the other hand, there are prospects for unconventional solar cells – Graetzel cells or polymer photovoltaics – which can perhaps be made cheaply in large areas, but whose efficiencies and lifetimes are too low. In an article in this month’s Nature Materials (abstract, subscription required for full article, see also this press release), Imperial College’s Keith Barnham suggests a way out of the dilemma.

The efficiencies of the best solar cells available today exceed 30%, and there is every reason to suppose that this figure can be substantially increased with more research. These solar cells are based, not on crystalline silicon, like standard solar cell modules, but on carefully nanostructured compound semiconductors like gallium arsenide (III-V semiconductors, in the jargon). By building up complex layered structures it is possible efficiently to harvest the energy of light of all wavelengths. The problem is that these solar cells are expensive to make, relying on sophisticated techniques for building up different semiconductor layers, like molecular beam epitaxy, and currently are generally only used for applications where cost doesn’t matter, such as on satellites. Barnham argues that the cost disadvantage can be overcome by combining these efficient solar cells with low-cost systems for concentrating sunlight – in his words “our answer to this particular problem is ‘Smart Windows’, which use small, transparent plastic lenses that track the sun and act as effective blinds for the direct sunlight, when combined with innovative light collectors and small 3rd-generation cells,” and he adds “Even in London a system like this would enable a typical office behind a south-facing wall to be electrically self-sufficient.”

Even with conventional technologies, Barnham calculates that if all roofs and south-facing walls were covered in solar cells this would represent three times the total generating capacity of the UK’s current nuclear program – that is, 36 GW. This represents a really substantial dent in the energy needs of the UK, and if we believe Barnham’s calculation that his system would deliver about three times as much energy as conventional solar cells, this represents pretty much a complete solution to our energy problems. What is absent from the article, though, is an estimate of the total production capacity that’s likely to be achievable, merely observing that the UK semiconductor industry has substantial spare capacity after the telecoms downturn. This is the missing calculation that needs to be done before we can accept Barnham’s optimism.

Nanoscience in the European Research Area

Most research in Europe, in nanotechnology or any other field, is not funded by the European Union. Somewhere between 90% and 95% of research funding comes from national research agencies, working with their own procedures, to their own national priorities. This bothers some people, who see this as yet another example of the way in which Europe doesn’t get its act together and thus fails to live up to its potential. In research, the European Commission fears that, compared to rivals in the USA or the far east, European efforts suffer from fragmentation and duplication. Their solution is the concept of the “European Research Area”, in which different national funding agencies work to create a joint approach to funding, as well as doing what they can to ensure free movement of researchers and ideas across the continent. As part of this initiative, national research agencies have come together to form thematic networks. Nanoscience has such a network, and it is meeting this week in Amsterdam to finalise the details of a joint funding call on the theme of singly addressable nanoscale objects.

Another way of looking at the issue of the many different approaches used in funding nanoscience across Europe is that this gives us a laboratory of different approaches, a kind of controlled experiment in science funding models. Yesterday’s meeting was devoted to series of overviews of the national nanoscience landscape in each country. This was instructive and contrasting; among the large countries one had the German approach, with major groups across the country being supported with really substantial infrastructure. The French had most logical and comprehensive overall plan, while the talk describing the British effort (given by me) couldn’t entirely hide its ad-hoc and largely unplanned character. The presentations from smaller countries varied from really rather impressive displays of focused activities (from the Netherlands, Finland and Austria in particular), to more aspirational talks from countries like Portugal and Slovakia.

How do the European nations rank in nanoscience? The undisputed leader is clearly Germany, with France and the UK vying for second place. Readers of this blog will know that I’m suspicious of bibliometric measures, but some interesting data was shown showing France second and the UK third by total numbers of nanoscience papers, but with that order being reversed when only highly cited papers were considered. But the efforts of the rich, smaller European countries are very significant; these are countries with high per person GDP figures which typically spend a higher proportion of GDP on research than larger countries. They combine this with a very focused and targeted approach to the science they support. The Netherlands, in particular, looks very strong indeed in those areas that it has chosen to concentrate on.