Polyvinylamine is applied in this paper to prepare the perovskite film as organic ammonium source. In this case

the perovskite crystal grains are linked together by the polymeric carbochain backbone through the A-site occupation on the surface of perovskite crystal grains via polymeric primary amines. The results of

1

H-NMR

SEM and XRD indicated that this kind of microscopic structure is able precisely to regulate the perovskite morphology due to the direct polymeric participation in the growing process of perovskite crystals

which will effectively improve the long-term stability of perovskite solar cells.