University of Sydney
A sponge that filters hot air and captures carbon dioxide
We need better ways of capturing carbon dioxide emissions from power stations and industry. And we won’t be using hydrogen cars until we’ve developed practical ways of carrying enough hydrogen gas in the fuel tank. Deanna D’Alessandro’s understanding of basic chemistry has led her to create new, incredibly absorbent chemicals that could do both these jobs and much more.
It’s all to do with surface area. Working in California and in Sydney she has constructed crystals that are full of minute holes. One teaspoon of the most effective of her chemicals has the surface area of a rugby field. What’s more, the size and shape of the pores can be customised using light. So she believes she can create molecular sponges that will mop up carbon dioxide, hydrogen, or in theory almost any gas – and then release it on cue.
Her achievements have won her a $20,000 L’Oréal Australia For Women in Science Fellowship which will provide equipment, travel support and a summer vacation student to assist her research.
A postdoctoral research fellow in the School of Chemistry at The University of Sydney, Deanna has always had a passion for chemistry. “At school I realised that chemistry explains everything – what colours the world, who we are, how we got here.” In return, chemistry has rewarded her passion – taking her around the world from her home town of Cairns. “I’ve presented my work in the US, UK, China and Europe. I love that aspect of science – it’s a global activity, a global community.”
Learning from nature
Deanna’s compounds are similar in principle to the molecular structures in seashells and in microscopic marine plants called diatoms. These naturally-occurring materials are commonly used in toothpaste, laundry detergents, kitty litter and industry generally.
Deanna’s high tech equivalents are crystals known as metal-organic frameworks – clusters of charged metal atoms linked by carbon-based groups. While she didn’t invent these frameworks, Deanna has developed new kinds which are more robust and which have molecular pores that can be shaped using light.
Many crystals have been made that can absorb carbon dioxide, but few can survive the hot, wet environment of a power station flue. The best carbon capture technology currently in use is based around toxic chemicals and uses about 40% of the energy generated by the power station.
During her time as a postdoctoral fellow at the University of California, Berkeley, Deanna created frameworks that could survive the tough environmental conditions and still capture carbon dioxide. They’re not ready for commercial use yet – but they are a step closer to cost-effective carbon capture.
Deanna will use her L’Oréal Australia For Women in Science Fellowship to help her take her crystals to the next level. She hopes to create more advanced molecular frameworks, the pores of which can be modified by different wavelengths of light. So, the crystals could be activated to absorb carbon dioxide with red light, for example, and to release it with light of another colour.
Her metal-organic frameworks could also have many other applications, such as hydrogen storage; gas separation; electrodes for sensors, and capacitors for electronic circuits.
In late 2009, Deanna returned to Australia to develop her own career as an independent researcher. “I’m building a research team here in Australia that will help me turn my ideas into reality and contribute to a sustainable future.”
2006 – PhD (Chemistry), James Cook University
2001 – Bachelor of Science with Honours (Chemistry), James Cook University
Career highlights, awards, fellowships, grants
2010-present – University of Sydney Postdoctoral Research Fellow, School of Chemistry, University of Sydney
2010 – James Cook University Outstanding Early Career Alumni Award
2008 – Sustainable Products and Solutions Program Grant, “CO2 capture in alkylamine-appended metal-organic frameworks”, awarded to D. M. D’Alessandro and J. R. Long
2007-2009 – Postdoctoral Research Fellow, Department of Chemistry, University of California, Berkeley, USA
2007-2009 – Royal Commission for the Exhibition of 1851 Research Fellowship. One of six awarded across Commonwealth countries
2007-2008 – Dow Chemical Company Foundation Fellowship of the American Australian Association
2007 – International Union of Pure and Applied Chemistry (IUPAC) Prize for Young Chemists for the most outstanding PhD theses in the chemical sciences (one of five awarded worldwide)
2007 – Fresh Science/British Council Australia study tour of the UK
2006-2007 – Postdoctoral Research Fellow, Molecular Electronics Group, University of Sydney
2006 – Royal Australian Chemical Institute (RACI) Cornforth Medal for the most outstanding PhD thesis submitted in a branch of chemistry in Australia
2003 – James Cook University Doctoral Research Scheme Grant to undertake research in the Centre for Nanotechnology, Northwestern University, USA
2001 – Australian Postgraduate Award
2000 – University Medal, James Cook University
- More than 25 presentations at Australian and international conferences and institutions, including eight invited conference and seminar presentations
- Twenty five publications including 16 first-author journal articles and four reviews (all as first author); and a further three articles for mainstream science publication
- Active role in undergraduate teaching at The University of Sydney as well as supervision of Honours students
Top five publications
D.M. D’Alessandro, B. Smit, J.R. Long, “Carbon dioxide capture: prospects for new materials”, Angewandte Chemie Int. Ed. 2010, published on the web 27/07/2010, DOI: 10.1002/anie.201000431. Impact factor: 11.025; Citation score: none available, in press.
B. Bechlars, D.M. D’Alessandro, D.M. Jenkins, A.T. Iavarone, S.D. Glover, C.P. Kubiak and J.R. Long, “High-spin ground states via electron delocalization in mixed-valence imidazolate-bridged divanadium complexes”, Nature Chemistry 2010, 2(5), 362-368.
Demessence, D.M. D’Alessandro, M.L. Foo and J.R. Long, “Strong CO2 binding in a water-stable, triazolate-bridged metal-organic framework functionalised with ethylenediamine”, Journal of the American Chemical Society 2009, 131, 8784-8786. Impact factor: 8.256; Citation score: 9.
D.M. D’Alessandro and F.R. Keene, “Current trends and future challenges in the experimental, theoretical and computational analysis of intervalence charge transfer (IVCT) transitions”, Chemical Society Reviews 2006, 35, 424-440. Impact factor: 17.730; Citation score: 43.
D.M. D’Alessandro and F.R. Keene, “Intervalence charge transfer (IVCT) in trinuclear and tetranuclear complexes of iron, ruthenium and osmium”, Chemical Reviews 2006, 106(6), 2270-2298. Impact factor: 28.577; Citation score: 48.