Rheological Tunability of Perovskite Precursor Solutions: From Spin Coating to Inkjet Printing Process.

The high efficiencies (>22%) reached by perovskite-based optoelectronic devices in a very short period, demonstrates the great potential and tunability of this material. The current challenge lies in translating such efficiencies to commercially feasible forms produced through industrial fabrication methods. Herein, a novel first step towards the processability of starch-perovskite inks, developed in our previous work, is investigated, by using inkjet printing technology. The tunability of the viscosity of the starch-perovskite-based inks allows the selection of suitable concentrations to be used as printable inks. After exploration of several printing parameters, thick and opaque starch-perovskite nanocomposite films were obtained, showing interesting morphological and optical properties. The results obtained in this work underline the potential and versatility of our approach, opening the possibility to explore and optimize, in the future, further large-scale deposition methods towards fully printed and stable perovskite devices.