ITIC is situated selectively on the interface of PTzBT and PCBM domains, which ends up in environment friendly generation of cost carriers (photocurrent). Photograph credit score: Itaru Osaka, Hiroshima College
Researchers at Hiroshima College in Japan have mixed collectively numerous polymer and molecular semiconductors as photograph absorbers to create a solar cell with elevated energy efficiency and power generation. A lot of these solar cells, referred to as natural photovoltaics (OPV), are units that generate electrical energy when mild falls on their photograph absorbers. The efficiency of a solar cell is set by evaluating how a lot electrical energy is generated and how a lot mild falls on the cell. This is named “photon harvest”, or what number of mild particles are transformed into electrical present. The extra environment friendly the solar cell, the cheaper and extra pragmatic the cell is for business use.
The Graduate College of Superior Science and Engineering workforce added only a small quantity of a compound that absorbs lengthy wavelengths of sunshine, leading to an OPV that was 1.5 instances extra environment friendly than the model with out the compound. The compound may enhance the absorption depth as a result of optical interference impact contained in the machine. The group additionally confirmed that their distribution is essential to additional enhancing power generation efficiency.
(a) ~ 100 nm thickness, (b) ~ 400 nm thickness. ITIC has three “absorption factors” when the semiconductor layer (PTzBT / PCBM / ITIC) is thick, whereas it has just one when the layer is skinny. That is as a result of elevated optical interference. Photograph credit score: Itaru Osaka, Hiroshima College
“The addition of a really small quantity of a sensitizing materials to an OPV cell made out of a semiconductor polymer that we developed beforehand and alongside with different supplies,” stated Itaru Osaka, correspondent creator of the paper, printed November 2020 in Macromolecules.
“This results in a major improve within the photocurrent and thus within the power conversion efficiency as a result of elevated photon absorption that outcomes from the optical interference impact. A secret is using a really particular polymer that permits us to have a really thick semiconductor layer for OPV cells, which significantly improves the optical interference impact in comparison with a skinny layer. ”
ITIC as a sensitizer exhibited an exterior quantum efficiency just like the host polymer PTzBT, though solely 6 wt% ITIC was added to the PTzBT / PCBM host supplies. Photograph credit score: Itaru Osaka, Hiroshima College
For future work, Osaka has set its sights on exceeding the boundaries of probably the most trendy solar cells.
“Our subsequent step is to develop higher semiconducting polymers to host one of these OPV and higher sensitization supplies that may soak up extra photons within the longer wavelength ranges. This is able to result in the belief of the world’s highest efficiency in OPV cells. ”
Reference: “Considerably sensitized ternary mixed polymer solar cells with a really low proportion of the third part with a slim band hole, which makes use of optical interference” by Masahiko Saito, Yasunari Tamai, Hiroyuki Ichikawa, Hiroyuki Yoshida, Daisuke Yokoyama, Hideo Ohkita and Itaru Osaka. November 25, 2020, Macromolecules.
DOI: 10.1021 / acs.macromol.0c01787
Funding: Japan Science and Know-how Company, Japan Society for the Development of Science
