Edited by Leonid A. Kosyachenko

Most solar modules used in photovoltaics are currently produced from crystalline and polycrystalline silicon wafers, the representatives of so-called first generation of solar cells. This type of devices are among the most efficient but at the same time the most expensive since they require the highest purity silicon and involve a lot of stages of complicated processes in their manufacture. Wafer-based silicon photovoltaics is giving place to thin-film technology, which provides much higher performance and lower cost of products, but inferior to silicon solar modules in photoelectric efficiency. Intensive search for materials and solar cell structures for photovoltaics is continuing. They are mostly yet too immature to appear in the market but some of them are already reaching the level of industrial production.

The second book of the four-volume edition of "Solar cells" is devoted to dye – sensitized solar cells (DSSCs), which are considered to be extremely promising because they are made of low-cost materials with simple inexpensive manufacturing procedures and can be engineered into flexible sheets. DSSCs are emerged as a truly new class of energy conversion devices, which are representatives of the third generation solar technology. Mechanism of conversion of solar energy into electricity in these devices is quite peculiar. The achieved energy conversion efficiency in DSSCs is low, however, it has improved quickly in the last years. It is believed that DSSCs are still at the start of their development stage and will take a worthy place in the large- scale production for the future.

It appears that chapters presented in this volume will be of interest to many readers.

Professor, Doctor of Sciences, Leonid A. Kosyachenko

National University of Chernivtsi Ukraine