Nature-inspired solar panels are self-healing
Nature's photosynthesis process far outperforms man-made light-energy-converting devices. The highly efficient mechanism for rapid separation and transfer of photo-excited charge pairs in the photosynthetic reaction center is a key step. In many thin-film solar-cell efforts, this charge separation is a critical challenge. In response, several fundamental studies have modeled nature's multistep charge-transfer process, which aids in precluding charge-pair recombination, or directly incorporated photosynthetic complexes into devices. Electrochemical solar-cell performance can also suffer from high light conditions or repeated exposures, damaging the donor dye molecules. Nature addresses this irreversible photodegradation elegantly by removing and replacing photodamaged components as often as once every hour. A group of researchers at Purdue University has been working on development of photovoltaic nanostructures with synthetic analogs to nature's efficient charge-separation and regeneration processes, forming the basis for a new class of electrochemical solar cells. Because of the combination of a high electron-accepting tendency and unmatched electrical-conductivity properties, carbon nanotubes have been subject of much attention in donor/acceptor nanohybrid studies. These aim to develop optimized hybrids of molecular donors and acceptors, the foundation for electrochemical solar-cell devices. As opposed to relying on either covalent or noncovalent interactions with donors such as porphyrins, ruthenium-based complexes, or semiconductor nanocrystals, Purdue University researchers have developed new strategies using highly functional biomolecules for direct noncovalent aqueous solubilization and functionalization of carbon nanotubes, preserving their electronic structure and unique properties. These biomolecules bind the donors with acceptors, and facilitate charge transport and regeneration. By varying the size of the biomolecule, it is possible to control the intermolecular distance between donor and acceptor, a critical aspect in charge-separation and recombination kinetics. Additionally, by changing the local environment, the structure of the biomolecule can be altered, modifying the binding conditions with the donor and allowing for removal and replacement with fresh donor molecules for optimal photoconversion. Source: SPIE Newsroom More info
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A solar reactor derived by a team from Caltech (California Institute of Technology), ETH Zurich and the Paul Scherrer Institute, could assist the thermo-chemical production of fuels.In a paper published in the journal Science, the researchers claim that fuel can be generated over 500 cycles. Solar to fuel efficiencies of 0.7-0.8 per cent were achieved. The basis for the system is a thermo-chemical cycle that disassociated water and carbon dioxide using nonstoichiometric ceria. It is designed to concentrate solar radiation and heating ranges from 1,420-1,6408C. This strips oxygen atoms from carbon dioxide and water, while forming CO and hydrogen respectively. According to the scientists this represents an attractive path to solar fuel production at high rates and efficiencies. Cerium oxide has emerged as a highly attractive redox active material choice because it shows rapid fuel production kinetics and high selectivity. However, to date these studies have been limited to bench-top demonstrations and an assessment of cyclability has been limited. Now, it has been demonstrated that high-rate solar fuel production can be achieved without the need for complex material microstructures and/or system design. The conversion efficiency obtained is about two orders of magnitude greater than was achieved with state-of-the-art photocatalytic approaches. It was also found that the efficiency and cycling rates in the reactor were limited largely by thermal losses and so the team anticipates that reactor optimisation and system integration will result in significant increases in efficiency and fuel production rates. 
At the Eco Products 2010 exhibition in Tokyo this past weekend, Sony showed intentions to bring new meaning to the phrase "flower power" with this beautifully designed Hana Mado, or 
