Highly Efficient and Reproducible Nonfullerene Solar Cells from Hydrocarbon Solvents

Highly Efficient and Reproducible Nonfullerene Solar Cells from Hydrocarbon Solvents

Andrew Wadsworth, Raja S. Ashraf, Maged Abdelsamie, Sebastian Pont, Mark Little, Maximilian Moser, Zeinab Hamid, Marios Neophytou, Weimin Zhang, Aram Amassian, James R. Durrant, Derya Baran, and Iain McCulloch. "Highly Efficient and Reproducible Nonfullerene Solar Cells from Hydrocarbon Solvents" ACS Energy Lett.  (2017), 2, 1494−1500 DOI: 10.1021/acsenergylett.7b00390​​​
Andrew Wadsworth, Raja S. Ashraf, Maged Abdelsamie, Sebastian Pont, Mark Little, Maximilian Moser, Zeinab Hamid, Marios Neophytou, Weimin Zhang, Aram Amassian, James R. Durrant, Derya Baran, and Iain McCulloch.
Nonfullerene, Solar Cells, Hydrocarbon Solvents
2017
​ABSTRACT: With chlorinated solvents unlikely to be permitted for use in solution-processed organic solar cells in industry, there must be a focus on developing nonchlorinated solvent systems. Here we report high-efficiency devices utilizing a low-bandgap donor polymer (PffBT4T- 2DT) and a nonfullerene acceptor (EH-IDTBR) from hydrocarbon solvents and without using additives. When mesitylene was used as the solvent, rather than chlorobenzene, an improved power conversion efficiency (11.1%) was achieved without the need for pre- or posttreatments. Despite altering the processing conditions to environmentally friendly solvents and room-temperature coating, grazing incident X-ray measurements confirmed that active layers processed from hydrocarbon solvents retained the robust nanomorphology obtained with hot-processed chlorinated solvents. The main advantages of hydrocarbon solvent-processed devices, besides the improved efficiencies, were the reproducibility and storage lifetime of devices. Mesitylene devices showed better reproducibility and shelf life up to 4000 h with PCE dropping by only 8% of its initial value.​