'Green chemistry' and artificial photosynthesis

Interviewer: Sam Walter (Interviewer, Ideas Lab)
Guest:  Dr Zoe Schnepp
Recorded: 11/01/2013
Broadcast: 04/03/2013

Intro VO: Welcome to the Ideas Lab Predictor Podcast from the University of Birmingham. In each edition we hear from an expert in a different field, who gives us insider information on key trends, upcoming events, and what they think the near future holds.

Sam: Today we’re here with Dr Zoe Schnepp who’s a Birmingham Fellow here in the School of Chemistry at the University of Birmingham.   Hello Zoe.

Zoe: Hello.

Sam: So, you describe yourself as a green chemist.  Could you describe a bit more about what you mean by that?

Zoe:  OK, so green chemistry is a term that was coined maybe about ten, twenty years ago and it’s more a way of describing a way of approaching chemistry. So the idea came about, obviously the chemical industry has developed a fairly bad reputation over the years and people are concerned with things like pollution and unsustainable ways of generating energy, so the idea of green chemistry is to approach any chemistry that we do while thinking about the whole process and thinking about things like what waste are we generating or what energy are we using in our process. So rather than being a field of chemistry, it’s actually just a sort of way of approaching any chemistry that you do.

Sam: So there are a lot of people around the world doing similar research in the area of -

Zoe: Yeah, because green chemistry spans, you know, well in theory all areas of chemistry, there’s people working with a focus on green chemistry all around the world. I obviously work in quite a specialised field within green chemistry and I work in materials chemistry so using sort of chemical ideas and the ideas, the training of chemistry and making functional materials, materials that could be integrated into useful devices, things that we use in our everyday lives.

Sam: So what’s different about what you do?

Zoe: One specific area that I’m working on is something called Artificial Photosynthesis and obviously again, there's hundreds of people in the world all working on this – industries and academics – all these sorts of people and the idea with this is to copy nature and to say, OK, well nature as an energy source uses the sun generally, so plants capture sunlight and they use the energy from that sunlight to convert water and carbon dioxide into sugars, and the plants can then store those sugars and use the sugars and then obviously animals depend on plants and so the whole cycle comes basically from the energy from the sun and obviously as humankind. We rely mostly for our energy on fossil sources, so the idea is can we copy nature? Can we copy this artificial photosynthesis and basically replicate it in the lab, or replicate it on a massive industrial scale? You know, can we make fuels using sunlight?

Sam: What is it within Artificial Photosynthesis that you’re doing differently?

Zoe: One of the things I’m interested in doing is one area of Artificial Photosynthesis which uses sunlight to split water. So basically we take water which is obviously H²O and we split that into Hydrogen and Oxygen separately, so gasses, and then we can use that Hydrogen and integrate it directly into this Hydrogen economy that obviously has been in the news a lot. Obviously again there's different ways of doing that, of splitting water and capturing sunlight to do that, but what a lot of people use and what is a really good material for doing that, often incorporates things like Platinum, which is fine and Platinum is a really great material for doing this in terms of activity and how it works, but obviously Platinum’s really expensive and the price of Platinum has obviously been rising massively over the last ten, twenty years.  On top of that, as well as Platinum being expensive it can be fairly environmentally damaging actually getting Platinum out of the ground and getting it ready for use.   So what I’m interested in specifically in my research is materials that could replace Platinum, so materials that sort of show us similar activity as Platinum but obviously based on much cheaper elements.

Sam:  What stage are you at in this?

Zoe: We’re really very much at the beginning. I’ve worked in the field of Platinum replacement for a little while now, not actually with a focus on Artificial Photosynthesis, we’ve been working on some materials for fuel cells, so you know the idea of having a fuel cell in your car, you can power your car on Hydrogen and you combine that Hydrogen with Oxygen and use that reaction to generate electricity to run your car.  Now obviously you can’t just throw Hydrogen and Oxygen in there, you need a catalyst, a material to make it work and again, these materials tend to use Platinum. So one of the things I’ve been working on previously is materials to replace Platinum in that application and in that respect we’ve been really successful and we made some really nice materials,  actually just using jelly, so you know the gelatine that you use to make just your regular jelly and now I’m try to apply some similar ideas.

Sam: If we’re going to see Artificial Photosynthesis as a reality commercially, domestically or on an industrial scale, what would it look like? How would it be implemented?

Zoe: Obviously there’s different ways you could implement this sort of technology. Certainly what I would say is that Artificial Photosynthesis isn’t as far on as some of the more well-known solar type technologies, so obviously solar cells that you see on people’s roofs in these solar panels, they’re obviously a lot further on in terms of their scientific advances and there’s obviously different ways of then implementing Artificial Photosynthesis. You could, in theory, have individual devices, so you could have a device like a solar panel that sits on someone’s roof. Obviously the ones we have at the moment, the solar panels generate electricity but what we might do is say generate Hydrogen and then find some way to store that and then you’d have your own little generator in your home to use that Hydrogen later on. It’s something that, you know, obviously the industrial implementation of this would have to be looked at very carefully. I mean certainly I’m working very much on the beginning steps of this.

Sam: Sure. Also there’s another eye-catching thing you’ve produced which is the Magnetic Leaf.

Zoe:  Yes, so this was actually starting when I was talking about the fuel cell materials, the Magnetic Leaf was actually the starting point for this and we ended up using, as I said, jelly, this gelatine material, but when we first started with this, I was interested in generally what biological materials can we use because in my research I’m really keen on using bio-resources, so materials from nature.  Well, often they’re waste materials, but also they can be chemically really complex and really interesting and we’re interested in, OK, can we harness that complexity? So the Magnetic Leaf, basically we took leaf materials, so we took a leaf skeleton and I just bought this from an arts and crafts shop and we converted that into a material that’s called iron carbide, and you find this material actually in steels and obviously in steels it’s used as a sort of structural material, but it can also be used as a catalytic material; a material that speeds up chemical reactions and so obviously in steels it’s in one great big chunk but the idea was when we used the leaf as a sort of template to make this material in a different form, we can make it with a really complex structure, replicating that original biological structure and because of that complex structure it might have different applications.  The leaf itself was supposed to be eye-catching, an eye-catching example of our work but obviously since then we’ve gone on to do it with much more maybe commercially viable materials.

Sam: Sure.

Zoe:  Like more cellular space materials.

Sam: So you’ve got this great green philosophy. How does your future research look? Does it implement this great green philosophy?

Zoe:  Absolutely.  So obviously I’ve worked for a few years now on using bio-resources and this is something I plan to continue in the future.  So Artificial Photosynthesis is just one example of the things we want to do but generally I’m really keen on researching what biological resources are there that we could use to make a useful material and particularly with the focus on waste materials because some biological materials are generated on a massive scale as waste products, so obviously in the paper making process, people pulp up trees and wood to extract the cellulose and there’s a material called lignin which is also in trees in a really high percentage and that at the moment, often it’s just burned or it’s thrown away and there’s a lot of examples of this where there’s a bio-resource that’s a waste material but if you look at it chemically, it’s fantastically complicated. So it's a shame just to burn it and what we’re interested in is can we use this for something useful?

Sam: So nothing is waste completely, there's always a use for something.

Zoe: Exactly and it’s this idea of cradle to cradle, so a lot of products that we have in our lives are cradle to grave. So we buy a product, we use it, we throw it away, and in the future I think industries are going to have to think a lot more carefully about all the resources that they use to make a product, what goes to waste within that and how they can either mitigate that and remove that as a waste stream, or, turn that waste stream into something useful, and I think that’s something industries are going to have to think about a lot more.

Sam: Dr Zoe Schnepp, thank you very much.

Zoe:  Thank you very much.

Outro VO: This podcast and others in the series are available on the Ideas Lab website: www.ideaslabuk.com. On the website, you can find out how to e-mail us with comments, questions or suggestions for future topics for the podcast. There's also information on the free support Ideas Lab has to offer to TV and radio producers, new media producers and journalists. The interviewer for the Ideas Lab Predictor Podcast was Lucy Vernall and the producer was Sam Walter.