Reproducible Fabrication of Perovskite Photovoltaics via Supramolecule Confinement Growth.

The solution processibility of perovskites provides a cost-effective and high-throughput route for fabricating state-of-the-art solar cells. However, the fast kinetics of precursor-to-perovskite transformation is susceptible to processing conditions, resulting in an uncontrollable variance in device performance. Here, we demonstrate a supramolecule confined approach to reproducibly fabricate perovskite films with an ultrasmooth, electronically homogeneous surface. The assembly of a calixarene capping layer on precursor surface can induce host-guest interactions with solvent molecules to tailor the desolvation kinetics, and initiate the perovskite crystallization from the sharp molecule-precursor interface. These combined effects significantly reduced the spatial variance and extended the processing window of perovskite films. As a result, the standard efficiency deviations of device-to-device and batch-to-batch devices were reduced from 0.64-0.26% to 0.67-0.23%, respectively. In addition, the perovskite films with ultrasmooth top surfaces exhibited photoluminescence quantum yield > 10% and surface recombination velocities < 100 cm s for both interfaces that yielded p-i-n structured solar cells with power conversion efficiency over 25%.