编辑: 霜天盈月祭 | 2019-07-07 |
His research covers the basic mechanisms of energy conversion in biology and chemistry, in particular the sunlight-powered splitting of water into oxygen and hydrogen fuel. Daniel Nocera tells about his research into harnessing solar energy to make fuel from water.? Could you briefly describe your own research?? My research is pretty easy to describe: water + light = oil. It is literally to figure out how to get light to act on water to split it into hydrogen and oxygen, which you can then use as a fuel.? Are there many groups working on this problem?? There are other groups working on it, but not enough, and that's what holds solar back. The way that science works, and this is what makes it beautiful, is that a discovery can come from anywhere. So if you want to up the ante in terms of discovery, you want to have as many people working on the problem as you can. There's a lot of really bright young people who could be working on it, but they don't because the money isn't there for them. I wish I had
150 competitors, because that's in the end how this problem will get solved.? But we practically spend no money on research in the world, especially on this problem. You should be able to run ITER and do all this other stuff, because the problem is too compelling to ignore it. My guess is it won't be the environment, it will be geopolitics and energy security that will turn people to this problem, and then the money will start flowing.? What do you see as the main hurdles to water splitting becoming a viable energy solution?? There are two keys - one is you have to make it cheaply, so you can mass-manufacture rather than have to make them a panel at a time. The second thing to figure out is the reaction chemistry on how to split water to hydrogen and oxygen. We don't know how to do that yet, even though plants do it every day. We can do the hydrogen part pretty well, but we still have no idea how to get the oxygen out - and you want to do that because you want a closed thermodynamic cycle. You want to be able to give somebody a gallon of water in the desert, make hydrogen and oxygen, and then have it recombine in a fuel cell to get water back again. It's going to take a concerted effort, we're going to need theoreticians, computational scientists, molecule builders - we really need to come together to make this happen. And there's no question these collaborations are forming;
a spirit in the community is forming.? You mentioned that plants have already mastered water splitting - shouldn't we just let them get on with it, and collect the biofuels?? Well, here's the key with plants - their theoretical limit of energy conversion is
10 per cent efficiency. Practically, the best stuff people hope to see some day is 2-3 per cent efficiency out of a plant. With solar PV, people walk in the door expecting
10 per cent efficiency - so they're starting off at the theoretical limit of a plant, and they expect to top out at 20-25 per cent efficiency. So that's the big difference, and the reason why I chose this problem and I didn't become a biofuels person. It's simple maths, you want to go where the ceiling is highest.? Are you optimistic that we'll solve these problems?? I know science will get there - we already know how to do it, it's just a question of doing it cheaply. And that's not easy, it's going to take massive new discoveries to make it cheap, but we can do it, I'm sure of it.? - 选自 英国皇家化学会《化学世界》,02 October