Subtitles section Play video Print subtitles I’ve got some Big Green News for you: scientists at the University of Waterloo in Canada have come up with a new design for an artificial leaf. That means a whole new way of making cleaner burning fuels using a process that mimics photosynthesis! But...what’s an artificial leaf? And could it really help us move away from the fossil fuels that are getting us into so much trouble? We’ve always been interested in figuring out how to copy plants, because they do a great job creating energy from the bare minimum. They take in water from their environment and absorb CO2 from the atmosphere. Add the energy boost of sunlight and voila, they’ve made glucose, or sugar that they use for energy (plus oxygen, and some leftover water). But instead of producing glucose and oxygen like plants do, artificial leaf tech aims to alter that process to produce fuel that we can use. The idea behind these bio-inspired technologies is to produce cleaner burning fuel while also scrubbing CO2 from the air and producing oxygen, so it’s no wonder that scientists have been trying to create one since the 70's. But there’s also a really good reason why they haven’t quite managed to make a fully-functioning commercial one yet. There are many parts of photosynthesis that are really hard to do if you’re not a plant. One is that you need a catalyst that interacts with light energy to split water into hydrogen and oxygen, a process called photolysis. Plants do this in their chloroplasts, the little energy production factories inside them that also hold the pigment that makes them green. Some teams have pursued this route, creating systems that just take light energy and make hydrogen, which can then be used as a fuel. But that’s slightly problematic not only because the actual process is really difficult, but because we don’t actually use hydrogen to power all that much yet. That’s why other teams are working to not only tackle photolysis, but to also come up with catalysts for the second hard thing: converting that resulting hydrogen and CO2 from the air into an alternative fuel. You know, something that could realistically be used as fuel now. And then after you do that, you just have to make sure the whole thing is scalable and cheap. So many groups around the world are vying to be the first to figure this out, or at least add something new to this growing body of knowledge. Recent work out of Cambridge University, for example, uses cobalt to turn water and CO2 into something called syngas, an industrial product that’s essential for making everything from plastics and medicines to agricultural products and alternative fuels. They hope to continue refining this process to eventually produce ethanol in just one step from only carbon dioxide and water. Can you beLEAF it?! But the latest breakthrough comes in red, not green. A Waterloo University-based team uses cuprous oxide as a catalyst that when mixed with CO2 and water and then exposed to light, turns into methanol (with a little oxygen on the side). And guess what?! We can use methanol as a fuel, and we do—often. It’s used in race cars, ocean freight shipping, some buses, lots of stuff! Importantly, this whole reaction occurs with no input of electricity, which makes it different from some previous efforts that have required electricity and so can be kind of inefficient and way too expensive to scale up. So the artificial leaf itself doesn’t take much energy to make and it absorbs CO2 from the air. And methanol, the fuel it produces, emits far fewer greenhouse gases and pollutants than gasoline. Even at their peak efficiency, plants only actually convert about 1% of the sunlight they absorb into stored energy, so there’s certainly room for improvement. And this latest artificial leaf tech is 10 times more efficient than plant photosynthesis, and is relatively simple, so the team hopes it could be easily scaled up. They hope to start using this tech to capture carbon from industrial power plants to make methanol, giving us a double whammy of pulling carbon out of the atmosphere and providing an alternative fuel. Various iterations of artificial leaf technologies are unfurling all over the world, building on each other and branching out in different directions. Not only does research like this provide us with alternatives to petroleum and petroleum byproducts, it could also decrease our demand for them altogether— an incentive we’re going to need more of as we grow into an uncertain future. If you want even more on alternative energy technologies, then check out this video here on how carbon nanotubes could revolutionize our solar energy, and make sure you subscribe to Seeker for all news leafy and green. Let us know what other topics like this you want us to cover down in the comments below, and as always, thanks for watching. I’ll see you next time.
B1 fuel leaf co2 artificial energy oxygen Artificial Leaf Technology Could One Day Power Our World 11 0 林宜悉 posted on 2020/03/25 More Share Save Report Video vocabulary