OREANDA-NEWS. Ricoh Co., Ltd. succeeded in developing a dye-sensitized solar cell consisting of only solid state material as an electrolyte, which substantially improves the power generation capacity under a weak light source. By using only solid state material as an electrolyte, the dye-sensitized solar cell ensures an advantage in safety and durability.

In addition, this solar cell achieved more than twice the generation of electric output under standard white LEDs (200 lux) compared to the electric output of amorphous silicon solar cells which have high power generation efficiency for indoor use in the current market. Characteristics such as safety, durability and the ability to keep generating electric power with high efficiency under weak light make it an ideal candidate for stand-alone power sources (allowing power generation without an external power) for sensors which are expected to enjoy greater demand from now on.

The dye-sensitized solar cell is getting a lot of attention as a next-generation solar cell, because it can generate an electric power efficiently under weak light such as scattered and indoor lighting. A general dye-sensitized solar cell utilizes visible light absorbed by the pigment in order to generate electric power. It is composed of a transparent conductive substrate which has a porous layer consisting of titanium dioxide particles with nano (a billionth) meter size, a glass substrate which has metal film and iodine electrolyte encapsulated between these substrates.

Despite being a promising candidate for next-generation solar cell, problems such as low generation efficiency, concern for safety (volatilization of iodine and organic solvent and electrolyte leakage) and durability (peeling-off of organic dye adsorbed on titanium dioxide) prevent it from being commercialized.

Ricoh found the solution to these problems by developing unique technologies in material, structure, and method for manufacturing. Since the structure of this solar cell device is similar to that of the organic photoconductor which is used for multifunction products (MFPs), Ricoh managed to make efficient use of its material and device technologies in developing this new cell.