Researchers in Linköping, Sweden, and Beijing, China, developed a new combination of donor and acceptor materials to be used as the active layer in an organic solar cell. The combination absorbs exactly the wavelengths of light used indoors.
The researchers describe two variants of an organic solar cell in an article in Nature Energy, where one variant has an area of 1 cm 2 and the other 4 cm 2. The smaller solar cell was exposed to ambient light at an intensity of 1000 lux, and the researchers observed that as much as 26.1 percent of the energy of the light was converted to electricity. The organic solar cell delivered a high voltage of above 1 V for more than 1000 hours in ambient light that varied between 200 and 1000 lux. The larger solar cell still maintained an energy efficiency of 23 percent, which is approaching the current maximum value.
"This work indicates great promise for organic solar cells to be widely used in our daily life for powering the internet of things", said Feng Gao, senior lecturer in the Division of Biomolecular and Organic Electronics at Linköping University.
"We are confident that the efficiency of organic solar cells will be further improved for ambient light applications in coming years, because there is still a large room for optimization of the materials used in this work," added Jianhui Hou, professor at the Institute of Chemistry, Chinese Academy of Sciences.