by Professor Thomas Fuance
Many exciting areas of nanotechnology research are converging on artificial
photosynthesis. The connection between the health of our plant and the humans it
sustains is now part of a growing field termed 'planetary medicine.' Would a
macroscience Global Artificial Photosynthesis (GAP) Project tackling critical
global energy, water and food problems be a definitive endeavour in planetary
nanomedicine? If so, how should it be initiated or organised?
Planetary medicine is now a growing field in which the expertise of medical
professionals in directed towards issues of global health and environmental
protection, particularly including climate change.1,2 Professor Tom Faunce's research seeks to expand upon his ideas
for a Global Artificial Photosynthesis (GAP) Project as a defining endeavour of
planetary nanomedicine. Professor Faunce presented these first at the
Nanotechnology for Sustainable Energy Conference sponsored by the
European Science Foundation in July 2010 at Obergurgl, Austria and at the 15th
International Congress of Photosynthesis in Beijing in August 2010.
At the Copenhagen Climate Conference in December 2009, the world's nation
states, created the Copenhagen Accord. This non-binding political agreement
recognized the critical impacts of population growth and fossil fuel-driven
climate change as well as the need to establish a comprehensive adaptation
program including international support for those countries most vulnerable to
its adverse effects.1 For the first time, all major
emitting countries agreed to a target of keeping global warming to less than 2°C
above pre-industrial levels. The Copenhagen Accord also contains important
undertakings concerning mitigation (including the Copenhagen Green Climate Fund)
in particular establishing a mechanism to accelerate renewable energy technology
development and transfer.3
The United Nations Millennium Development Goals are particularly
focused on related issues of energy storage, production and conversion,
agricultural productivity enhancement, water treatment and remediation and
experts have encouraged nanotechnology to systematically contribute to their
achievement.4 These critical survival issues for the
poor will be exacerbated as global population grows towards 10 billion by 2050
and energy consumption rises from 13.5 TW (2001) to ˜40.8 TW. Artificial
photosynthesis (AP) involves an exciting convergence of nanotechnology research
on such problems. Would a 'big science' approach to AP represent a defining
exercise in planetary nanomedicine?
Photosynthetic organisms absorb photons from various regions of the solar
spectrum into "antenna" chlorophyll molecules in cell membrane thylakoids,
plants do the same in intracellular organelles called chloroplasts. The absorbed
photons' energy is used by the oxygen-evolving complex (OEC) in a protein known
as photosystem II to oxidize water (H2O) to oxygen (O2)
which is released to the atmosphere. The electrons thereby produced are captured
in chemical bonds by photosystem I to reduce NADP (nicotinamide adenine
dinucleotide phosphate) for storage in ATP (adenosine triphosphate) and NADPH
(nature's form of hydrogen).5 In the "dark reaction"
ATP and NADPH as well as carbon dioxide (CO2) are used in the
Calvin-Benson cycle to make food in the form of carbohydrate via the enzyme
Photosynthesis, the ultimate source of our oxygen, food and fossil fuels,
already traps ˜100 TW of 150,000 TW solar energy striking the earth. Nanoscience
researchers are actively redesigning photosynthesis to achieve, for example, low
cost, localised, conversion of sunlight and dirty water into fuel for heating
and cooking.7 Enhanced AP, if applied equitably,
could assist crop production on marginal lands, reduce atmospheric
CO2 levels, lower geopolitical and military tensions over fossil
fuel, food and water scarcity and create hydrogen for industrial storage.8
AP is driven by nanotechnology advances intersecting with multiple scientific
disciplines. Examples include water oxidation systems utilizing photosensitive
components grafted by core-shell nanowires to a genetically engineered
Two-dimensional Fourier transform electronic spectroscopy enhancement has
shown that photosynthetic electron pathways are essentially performing a single
quantum computation, sensing many states simultaneously suggesting a mechanism
for enhancing the efficiency of the energy transfer of quantum dots' light
harvesting capabilities by quantum coherence mechanisms,11 mesoporous thin film dye-sensitive solar cells of
semiconductor nanoparticles12 and carbon nanotubes
harvesting and conducting the resultant electricity.13
An inexpensive (non rare-metal) water catalytic system has been tested which
is self-repairing and allegedly operates under ambient conditions at neutral pH
with non-pure water.14 Synthetic proteins
(maquettes) have been created to allow testing of engineering principles for
artificial photosystems and reaction centers.15
Numerous competitively funded nanotechnology-focused AP research teams
already exist in many developed nations.16 A dozen
European research partners form the Solar-H AP network, supported by the
European Union. The US Dept. of Energy (DOE) Joint Center for Artificial
Photosynthesis (JCAP) led by the California Institute of Technology
(Caltech) and Lawrence Berkeley National Laboratory has US$122m over 5 years to
build a solar fuel system. Caltech and the Massachusetts Institute of Technology
have a $20 million National Science Foundation (NSF) grant to improve photon
capture and catalyst efficiency, while several Energy Frontier Research Centers
funded by the US DOE are focused on AP.
A GAP Project must overcome various organizational, financial and
intellectual property challenges. The scientific challenge for the Human Genome
Project HGP was perhaps more clearly defined. As with the HGP, GAP Project work
is likely to be distributed across a variety of laboratories in different
nations, rather than being focused in one place like the European Organization
for Nuclear Research (CERN) or the international project on fusion energy
CERN's lesson may be to have many nations funding new equipment (such as the
Large Hadron Collider) open to use by independently-funded physicists from
around the world. ITER highlights the benefits of signatories agreeing to share
scientific data, procurements, finance, staffing. As with CERN, the Hubble Space
Telescope (funded by NASA in collaboration with the European Space Agency)
allows any qualified scientist to submit a research proposal, successful
applicants having a year after observation before their data is released to the
entire scientific community.
Industry involvement (either as suppliers of equipment or resources or
customers of outputs) in a GAP project will be a major issue given the tensions
between public and private rights exhibited in the final stages of the HGP.
Lessons from the SEMATECH (SEmiconductor MAnufacturing TECHnology) non-profit
consortium, may be that while large scale national funding and industry partners
are necessary for initial momentum, global impact requires inclusion of industry
from multiple nations and division into pure research and manufacturing
The Center for Revolutionary Solar Photoconversion (CRSP) involves
public funding from two separate sources (US DOE and NSF) with multinational
corporate members (including DuPont, General Motors, Konarka, Lockheed Martin,
Sharp and Toyota). Coordination with international renewable energy
organizations such the International Renewable Energy Agency (IRENA) and the
World Council for Renewable Energy (WCRE) and EUROSOLAR, the non-profit European
Association for Renewable Energy will be important for GAP Project regulatory
stability and credibility.
Potential governance models for a GAP Project could either involve gradual
evolution from the status quo, or active promotion and coordination by the
International Society of Photosynthesis Research (ISPR) in collaboration with
leaders of the largest national AP projects. An open-access model might see
funding rules requiring public good licensing, technology transfer, ethical and
social implications research as well as rapid and free access to data.
A public-private partnership model might involve members' access to
non-exclusive licenses over intellectual property as with CRSP. A governance
structure emphasizing international law might protect photosynthesis from damage
or excessive patents within the class of United Nations treaties involved with
protecting the common heritage of humanity (for instance moon, outer space, deep
sea bed, world natural heritage sites) with obligations to roll out AP
Capturing, converting and storing secure, carbon-neutral, sustainable energy
from its most abundant source, the sun may be the most important scientific and
technical challenge facing humanity in the 21st century. A multidisciplinary GAP
Project could be a definitive exercise in planetary nanomedicine.
- McMichael T: The biosphere, health and "sustainability" Science
297(5584), 1093 (2002).
- Schwartz BS, Parker C, Glass TA, Hu H: Global environmental
change: what can health care providers and the environmental health community
do about it now? Environ Health Perspect 114 (12), 1807-12 (2006).
- United Nations. Framework Convention on Climate Change. Draft
decision -/CP.15 CONFERENCE OF THE PARTIES Fifteenth session Copenhagen, 7-18
December 2009 FCCC/CP/2009/L.7 18 December 2009
- Salamanca-Buentello F, Persad DL, Court EB, Martin DK, Daar AS et al:
Nanotechnology and the Developing World. PloS Med. 2, e97 (2005).
- Blankenship RE: Molecular Mechanisms of Photosynthesis. Blackwell Science,
- Gust D and Moore TA: Mimicking photosynthesis. Science 244,
- Hurst JK: In pursuit of water oxidation catalysts for solar
fuel oxidation. Science 328, 315-316 (2010).
- Pace R: "An Integrated Artificial Photosynthesis Model" in
Collings A and Critchley C. Artificial Photosynthesis: from basic biology
to industrial application. Wiley-VCH Verlag. Weinheim. 13-34 (2005).
- Nam YS, Magyar AP, Lee D, Kim JW, Yun DS, Park H, Pollom
TS, Weitz DA, Belcher AM: Biologically templated photocatalytic nanostructures
for sustained light-driven water oxidation. Nature nanotechnology. 5(5), 340-4
- Nam YS, Shin T, Park H, Magyar AP, Choi K, Fantner G, Nelson
KA, Belcher AM Virus-templated assembly of porphyrins into light-harvesting
nanoantennae. Journal of the American Chemical Society. 132(5),1462-3 (2010)
- Engel GS, Calhoun TR, Read EL et al: Evidence for wavelike
energy transfer through quantum coherence in photosynthetic systems Nature.
446, 782-786 (2007).
- Kalyanasundaram K. & Graëtzel M: Artificial photosynthesis: biomimetic
approaches to solar energy conversion and storage Curr. Op. Biotech. 21, 298-310
- Sgobba V & Guldi DM: Carbon nanotubes-electronic/electrochemical
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38, 165-184 (2009).
- Kanan MW and Nocera DG: In situ formation of an oxygen-evolving catalyst
in neutral water containing phosphate and CO2. Science 321, 1072-1075
- Koder et al: 'Design and engineering of an O2
transport protein' Nature. 458, 305-309 (2009).
- Sanderson K: The photon trap. Nature 452: 400-4002 (2008)
Copyright AZoNano.com, Professor Thomas Faunce (Australian