Nearly all solar cells today are made of silicon, which is costly and difficult to produce. Now, however, a scientist in Switzerland has created solar cells from titanium dioxide molecules that react to photons to create electricity. Titanium dioxide, while not as efficient as silicon, is inexpensive and is a common manufacturing chemical.
Professor Grätzel, of the Swiss Federal Institute of Technology of Lausanne, had used nano technology to create the cells and then sensitize them with a dye that captures the photons that land on the solar cell. These cells are now called Grätzel cells, and we expect to be hearing a lot about them in the future.