Pseudo-Planar Organic Heterojunctions by Sequential Printing of Quasi-Miscible Inks

This work deals with the interfacial mixing mechanism of picoliter (pL)-scale droplets produced by sequential inkjet printing organic-based inks onto ITO/PET surfaces at a moderately high Weber number (~101). Differently from solution dispensing processes Bond such as spin coating, deposition is strictly controlled droplet velocity, ink viscosity, and surface tension. In particular, this study considers containing most investigated donor/acceptor couple for organic solar cells, i.e., poly(3-hexylthiophene) (P3HT) (6,6)-phenyl-C61-butyric acid methyl ester (PCBM), showing how low-viscosity low-surface energy can be leveraged fabrication an interface suitable pseudo-planar heterojunction (pseudo-PHJ) cell (OSC) that convenient alternative to bulk (BHJ) OSC. The resulting thin-film morphology molecular organization P3HT/PCBM are investigated, highlighting roles dissolution-driven recirculation. report represents first step toward pseudo-PHJ OSCs low consumption solvents/chemicals.