Published on August 5th, 2013 | by James Ayre5
More Sustainable Solar Cells From Cobalt
August 5th, 2013 by James Ayre
More environmentally friendly and cheaper solar cells could be manufactured using cobalt, new research as found. Researchers from the University of Basel have developed a copper-based, dye-sensitized solar cell where the expensive (and relatively rare) element iodine has been replaced by the much more common element cobalt. The new Cu-Co solar cell — as it’s been dubbed — shows no loss of performance as compared to more conventional iodine-containing, dye-sensitized solar cells.
Some context: Dye-sensitized solar cells (DSCs) are a type of solar cell that works by capturing sunlight via a colored dye, which then, through an electron transfer process, produces electrical current. Electrolytes function as the electron transport agents. In conventional DSCs, iodine and iodide are the typical electrolytes used.
According to the researchers, this new replacement significantly improves the potential sustainability of solar cells: “Iodine is a rare element, only present at a level of 450 parts per billion in the Earth, whereas cobalt is 50 times more abundant,” states Project Officer Dr Biljana Bozic-Weber. “Furthermore, this replacement also removes one of the long-term degradation processes in which copper compounds react with the electrolyte to form copper iodide and thus improves the long-term stability of DSCs.”
While this new research represents a great step towards the goal of stable iodide-free copper solar cells, there are still some issues that need to be worked out before commercialization can begin, in anything other than niche markets that is.
“In changing any one component of these solar cells, it is necessary to optimize all other parts as a consequence,” states Ed Constable, a chemistry professor at the University of Basel. “This is part of a new approach termed ‘Molecular Systems Engineering’ in which all molecular and material components of a system can be integrated and optimized to approach new levels of sophistication in nanoscale machinery.”