Iron based dyes offer cheaper route to solar energy
13 October 2015
Researchers at Lund University in Sweden have found a new way to capture energy from sunlight – by using molecules that contain iron.
Researchers at Lund University have been working on solar cells consisting of a thin film of nanostructured titanium dioxide and a dye that captures solar energy. Today, the best solar cells of this type use dyes containing ruthenium metal – a very rare and expensive element.
“Many researchers have tried to replace ruthenium with iron, but without success," says Lund's Professor Villy Sundström. "All previous attempts have resulted in molecules that convert light energy into heat instead of electrons, which is required for solar cells to generate electricity."
Researchers at the Chemistry Department in Lund, in collaboration with Uppsala University, have now successfully produced an iron-based dye that is capable of converting light into electrons with nearly 100 percent efficiency.
“The advantage of using iron is that it is a common element in nature. It can provide inexpensive and environmentally friendly applications of solar energy in the future”, says Lund's Professor Kenneth Wärnmark.
By combining the experiments with advanced computer simulations, the researchers are able to understand in detail how the iron molecules work, and this knowledge is now being used to further develop the iron-based dyes. More research is needed before the new solar cell dye can be used in practice, but the team is optimistic.
The results of the study suggest that solar cells based on these materials can be at least as effective as those of today that are based on ruthenium or other rare metals,” says Sundström.
Wärnmark believes the new iron-based molecules could also drive the chemical reactions that create solar fuel.
The results of this work are presented in the latest issue of Nature Chemistry.