Using Fruit To Aid The Sun’s Work

Blackberries, blueberries, oranges and grapes—chemistry students at Rowan University (Glassboro, N.J.) are loading up on their fruits these days, but it has nothing to do with the food pyramid.

The students (John Manganaro, 21, a senior chemistry major from Monroeville; Dave Lawrence, 23, a junior chemistry and physics major from Jackson; Anthony Antonelli, 21, a senior chemistry and biochemistry major from Bellmawr; and Bill Green, 22, a senior chemistry major from Port Norris) are using the fruit to produce solar energy.
The Rowan researchers are working to refine a process in which they extract dye from a range of fruit and blend it into a kind of scientific “smoothie.” They separate out the heavy particles using filters and a centrifuge to obtain a liquid, which they freeze dry. The process leaves the researchers with sugar and a dye. They separate the components and obtain pure, brightly colored dyes in an acidic solution.

“We completely developed this process ourselves,” said Manganaro.

From there, they place the dye on a conductive glass coated with a porous film of titanium dioxide—a material found in everything from toothpaste to sandwich cookies to white paint—which bonds the dye to the glass. Finally, they add iodine and potassium iodide electrolyte for dye regeneration.

When light hits the processed fruit dye on the glass, it “excites” the electrons, which mobilizes or “frees” them. The electrons travel to a conductive glass electrode. That, in turn, produces electricity.

Science Daily