Dye-Based Solar Cell Sets New Efficiency Record

Flexible, low cost, lightweight solar panels may soon become a viable new source of mainstream electric energy with the help of a new type of solar cell invented recently at the Changchun Institute of Applied Chemistry at the Chinese Academy of Sciences and the Swiss Federal Institute of Technology, incorporating organic materials instead of typical rigid ones, such as silicon. The new solar cell is also said to have a high efficiency and high stability, lacking the volatile chemicals that are currently used in the construction of solar panels.

"We have uncovered new findings on old solar-cell materials and created high-performance cells," said Peng Wang of the Changchun Institute of Applied Chemistry, part of the team detailing the new findings.

The new prototype is formed of three major components, two of which being semiconductors while the other is an electrolytic liquid formed out of a salt dissolved in a solvent. As sunlight hits the solar cell, the electrolytic solution and the semiconductors work together in splitting the electron-hole pairs created by the photosensitive dye while absorbing photons of light.

According to the research team, this design has and efficiency rate of 8.2 percent, while the conversion rates of some of the most efficient dye-sensitized solar cells reach a maximum of 11 percent. Generally, high efficiency dye-based cells also contain volatile solvents in the electrolytic solution, which eventually escape through the plastic seals of the cell, presenting potential risk for the environment.

The prototype showed by Wang presents no such solvents, having electrolytes created out of a mix of three solid salts dissolved inside a special liquid solvent, allowing impressive conductivity and stability. "The performance of our solar cell now matches that of cells that use volatile solvents. This is an important step toward the production of large-scale outdoor dye-sensitized solar cells," said Wang.