Inverted photovoltaic cells of nanocolumnar C60 filled with solution processed small molecule 3-Q

Nanocolumnar C60 films for inverted organic photovoltaic cells (OPVs) were fabricated by glancing angle deposition (GLAD), and morphologies depending on variation in deposition angle were studied. To complete the OPV devices, small molecules of the donor material 3-Q were spin coated into the C60 films. In order to avoid the difficulties of solvent stability of the C60 films, acetone was used as the process solvent for spin coating. The nanocolumnar morphology improves exciton harvesting by increasing absorbance while providing an effective conductive path for charge carriers. The resulting GLAD C60/3-Q devices outperformed both planar devices and PC61BM:3-Q bulk heterojunctions with threefold and twofold short-circuit current increases, respectively.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Nanocolumnar C60 films fabricated using glancing angle deposition (GLAD). ► JSC doubled in GLAD C60 film devices relative to bulk heterojunction devices. ► Acetone as process solvent for donor spin coating in GLAD C60 films investigated.