Our new paper, “Two-dimensional perovskite templates for durable, efficient formamidinium perovskite solar cells,” is now online onScience. In this paper, Isaac and Dr. Sidhik present a design strategy for fabricating ultrastable phase-pure films of formamidinium lead iodide by lattice templating using specific two-dimensional perovskites with FA as the cage cation. We thank all our collaborators…