Multiscale morphology design of hybrid halide perovskites through a polymeric template

Hybrid halide perovskites have emerged as promising active constituents of next generation soln. processable optoelectronic devices. During their assembling process, perovskite components undergo very complex dynamic equil. starting in soln. and progressing throughout film formation. Finding a methodol. to control and affect these equil., responsible for the unique morphol. diversity obsd. in perovskite films, constitutes a fundamental step towards a reproducible material processability. Here we propose the exploitation of polymer matrixes as cooperative assembling components of novel perovskite CH3NH3PbI3 : polymer composites, in which the control of the chem. interactions in soln. allows a predictable tuning of the final film morphol. We reveal that the nature of the interactions between perovskite precursors and polymer functional groups, probed by NMR (NMR) spectroscopy and Dynamic Light Scattering (DLS) techniques, allows the control of aggregates in soln. whose characteristics are strictly maintained in the solid film, and permits the formation of nanostructures that are inaccessible to conventional perovskite depositions. These results demonstrate how the fundamental chem. of perovskite precursors in soln. has a paramount influence on controlling and monitoring the final morphol. of CH3NH3PbI3 (MAPbI3) thin films, foreseeing the possibility of designing perovskite : polymer composites targeting diverse optoelectronic applications.