Scientist sees the light
In the course of one hour, the Earth receives more solar energy than the entire planet consumes in a whole year.
Little of the energy is harvested in the form of solar energy. Conventional solar panels use semiconductor materials and the energy gathered is some five to six times more expensive than that which has been generated by fossil fuels or hydro-electric power. Teams around the world have striven to develop a solar cell which could be produced inexpensively and which is efficient, in energy terms.
Professor Benoît Marsan and his team at the Université du Québec à Montréal have focussed their research energies in the development of a electrochemical solar cell. Their work was inspired by research of the 1990s which looked to generate energy in a way similar to plants, ie photosynthesis. This involved placing a liquid electrolyte between the anode and cathode, composed of a porous layer of nano-particles of a white pigment, titanium dioxide, covered with a molecular dye that absorbs sunlight, like the chlorophyll in green leaves. However, such approaches quickly showed that the materials used were highly corrosive, the dense colour inhibited the transmission of light, the photovoltage was only 0.7 volts and the platinum cathode was expensive.
Profesor Marsan appears to have produced a satisfactory solution to these ‘challenges’. They have created new molecules to form the electrolyte, and the gel produced is transparent and importantly non-corrosive. They have replaced the platinum cathode with cobalt sulphide, and the result is a more efficient, cheaper, more stable solar cell which should be easy to produce. Would it be too much to say the future looks bright ?