Andrew Holmes: silicon solar cells will be difficult to beat with the organic materials but not impossible
Pavel Korolev: Hello, everyone! This is the next chat with the nominees from our shortlist and in touch with us is Dr Andrew Bruce Holmes. Hello sir.
Andrew Holmes: Hello, it's very nice to meet you, thank you for the invitation.
Pavel Korolev: My name is Pavel Korolev, vice president for the Global Energy Association and with me today is Sophia Morgan, deputy vice president of the Global Energy Association. Dr Andrew Bruce Holmes was nominated this year “for leadership in the field of organic electronic material synthesis and device applications for energy efficient organic and polymer light emitting diodes and thin film solar cells”. Professor Holmes became interested in conjugated polymers this led to the discovery of the first polymer light emitting diodes
Sophia Morgan: Yes, as you might probably know two of our laureates Shuji Nakamura and Nick Holonyak, who is by the way the father of LEDs received the Global Energy Prize and one of them later won the Nobel Prize, so how do your polymer diodes differ from what we used before?
Andrew Holmes: Well the thing that the Nakamura prize particularly recognized was the blue LED the blue inorganic led, I call them inorganic they're made of materials based on gallium, indium, nitride and so on. Gallium, indium, nitride and they're excellent and that was a big breakthrough because if you don't have blue, you can't get the full color spectrum. In the organic area the beauty of organic materials is that you have the principle there of spreading them over large areas whether you deposit them by vapor deposition or as the polymers from solution you can make large areas if you look at LEDs from inorganic materials, they're small materials they're small dots and you have to have lots of small dots to cover a large area. So the advantage I think of the organic materials in the first instance is that they can be spread over large areas particularly and getting the blue organic LED was just as hard as getting the blue inorganic LED.
Pavel Korolev: Professor Holmes, how has polymer technology affected solar cells?
Andrew Holmes: The both fields, both the light emitting materials the LEDs, organic LEDs and the solar cells, based on organic materials have had two parallel strands. The devices made with molecular materials, which can be deposited by evaporation, vapor deposition and polymer materials largely although the organic can as well from solution. So, the polymer large area advantage by solution deposition is the main difference and in all the devices some use of organic polymeric materials has been made to enhance the charge separation. Solar cell works by forcing the light to separate its charge to split into the positive and negative charges, and that's the challenge and the interface is where that happens and that can be done with polymers as well as with small molecular materials.
Pavel Korolev: Thank you, we have several nominees from Australia this year. Years ago as you know Martin Green won the Prize. You were the president of Australian Academy of science, according to the forecasts that Academy of Sciences releases every year, what is Australia's energy mix now and how did Covid affects this?
Andrew Holmes: Well Australia's energy needs is in the I think about the 50 gigawatts, if I remember I haven't done my homework on this today, but the energy need the bottom line is that the bulk of Australia's electricity energy needs is from fossil fuels and largely coal and the impact that Martin Green has done he's our hero in the area of solar cells is to have introduced to the world really the technology for developing low energy silicon solar cells and they're going to be a technology which will be difficult to beat with the organic solar materials but not impossible. When we formed our consortium, I went to Martin Green and asked him to be chair of our advisory committee. He said yes, I'll do it but I still believe that my solar cells are the best. But what is quite interesting is with the advent of perovskite solar cells Martin himself is also working in that area now and so at the kind of convergence it makes me very pleased.
Pavel Korolev: Thank you!
Sophia Morgan: So, this year you are the second nominee who working with materials makes not a contribution only to energy but also to the medicine collaborating with the Ludwig cancer institute. What interesting things you can tell about this to our subscribers now?
Andrew Holmes: Well, if I may backtrack a little bit um I started life as a synthetic organic chemist making the kinds of molecules that are useful for drug discovery in medicinal chemistry and it was only by accident that we made a polymer one day which turned out to be interesting, to be a kind of potential conducting polymer and that took me into the field of conjugated polymers. But the other half of my life which is slowly been overtaken by the organic electronic materials has been making molecules for medicinal and chemistry and for chemistry to be used in biology. When we were in the UK we started putting molecules that are involved in signal transduction that is communication in between cells we put them on fishing lines with our collaborators and extracted proteins involved in signaling from the brains of pigs and sheep and that uncovered a whole lot of new proteins and signaling in that area. When we came to Australia we found partners in the Ludwig cancer institute and then later in the Walter and Eliza hall institute who were interested in doing the same thing for signaling molecules in colon cancer and we found to our delight that the technology work just as well in cells from colon cancer and again we identified numerous proteins that are involved in communicating things between cells to promote cell growth and cell division and of course if you could find a way of interfering with that you might find a way of inhibiting cell division and therefore inhibiting and promoting cell death which is one of the ways of dealing with cancer.
Sophia Morgan: I would only like to wish you good luck in these two extremely important areas.
Andrew Holmes: Thank you, I need all the luck that you can wish.
Sophia Morgan: Our congratulations for you being shortlisted. We wish good luck to all our nominees, so wish you once again
Pavel Korolev: So, good luck!
Andrew Holmes: It's extreme honor to be nominated and I'm very honored to have this interview with you, thank you very much.
Pavel Korolev: thank you and have a good day!