[12a-S221-1~12] 12.5 Organic solar cells

[12a-S221-7] Colorful Squaraines for Efficient Solution-Processed Small Molecule Semitransparent Organic Solar Cells

〇TAKESHI SANO¹, Daobin Yang¹, Yuya Hayashi¹, Hisahiro Sasabe¹, Junji Kido¹ (1.Yamagata Univ.)

Keywords:organic solar cells, organic photovoltaic cells, semitransparent

Semitransparent organic solar cells (ST-OSCs) are considered to become one of the highest priorities in the market of next-generation solar cells, because ST-OSCs enable wearable electronics, solar-powered automotive, power-generating windows, and building integrated photovoltaics. However, the development of ST-OSCs is significantly lagging behind opaque OSCs, particularly in small molecule ST-OSCs. Herein, four unique squaraines (SQ-R2, SQ-BP, D-BDT-SQ, and AzUSQ) are successfully used as donors in ST-OSCs, whose colors can be tuned from red to blue, green, and dark green, respectively. While using transparent electrodes, the ST-OSCs with these squaraines yield power conversion efficiencies of from 1.6% to 4.9%. Furthermore, each of these ST-OSCs exhibit good average visible transmittance of 25%–30%. This result indicates that squaraines should be considered as promising candidates to promote the development of colorful ST-OSCs.