The use of sunlight is of particular interest among renewable energies.Solar cells are indispensable for the use of sunlight.Currently, various types of solar cells have been developed, and they are being considered for proper use according to the situation in which they are used.The main ones are inorganic solar cells made from silicon and organic thin-film solar cells made from organic substances.Inorganic solar cells are currently the most efficient solar cells that can generate electricity, but they have the problem of extremely high production costs, such as the processing of silicon plates.On the other hand, although the power generation efficiency of organic thin-film solar cells is inferior to that of inorganic solar electrons, they are manufactured by dissolving a semiconductor polymer in a special ink on a resin sheet and applying it, so there is an advantage that the cost is very low.Increasing the efficiency of organic thin-film solar cells is a major barrier to the widespread use of solar cells.

　The research group created an organic thin-film solar cell using a newly developed semiconductor polymer called PNOz4T.In conventional matter, after absorbing light energy into the matter, electrons move inside the matter.This was one of the causes of large energy loss in organic thin-film solar cells.On the other hand, PNOz4T says that after absorbing light energy in a substance, electrons can be taken out as electric power without moving in the substance.In this way, we succeeded in suppressing energy loss as much as an inorganic solar cell.

　If the performance of PNOz4T can be maximized, it is said that the power generation efficiency of 15%, which is said to be the minimum condition for practical use, can be achieved.It is also expected that the knowledge gained from this research will be applied to organic thin-film solar cells other than PNOz4T to dramatically improve power generation efficiency.