Green-Light Wavelength-Selective Organic Solar Cells Based on Poly(3-hexylthiophene) and Naphthobisthiadiazole-Containing Acceptors toward Agrivoltaics

The complemental absorption behavior of donors and acceptors in organic solar cells (OSCs) results in the broad absorption of solar light, contributing to the realization of high-performance OSCs. However, the development of OSCs with narrow absorption ranges, i.e., wavelength-selective OSCs, has made slow progress owing to their limited applications. Here, green-light wavelength-selective OSCs, whose transmitted blue and red light can be effectively used to promote plant growth, are proposed. For the preparation of green-light wavelength-selective OSCs, a practical polymer of poly(3-hexylthiophene) (P3HT) is employed as the donor and naphthobisthiadiazole-based compounds (SNTz-RD and ONTz-RD) are newly designed as the acceptors. The electronic absorption measurements of SNTz-RD and ONTz-RD show strong absorption bands in the green-light region. In addition, SNTz-RD and ONTz-RD possess appropriate frontier orbital energy levels as acceptors. OSCs based on P3HT and these acceptors show typical photovoltaic responses with good green-light wavelength-selective factors and good power conversion efficiencies in the green-light region. Furthermore, the P3HT:SNTz-RD blend films exhibit an improved photosynthetic rate in the strawberry leaves compared to the conventional P3HT:[6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) film. These results demonstrate that the combination of P3HT and green-light wavelength-selective acceptors can produce green-light wavelength-selective OSCs for application in new greenhouse agrivoltaics.