π-π conjugate structure enabling the channel construction of carrier-facilitated transport in 1D–3D multidimensional CsPbI2Br solar cells with high stability

All-inorganic CsPbIxBr3−x (0 ≤x ≤ 3) perovskites are expected to fundamentally solve the thermal stability issue of perovskite solar cell toward its final commercialization. However, the humidity stability of this class of all-inorganic perovskite is still not intrinsically tackled out. Herein, aminoquinoline is introduced to construct a thus far unreported one-dimensional (1D) perovskite, in which the distorted [PbI6]4- octahedra display a shoulder-by-shoulder arrangement along the [001] direction, and A-site quinoline (Aq) organic groups with π-π conjugate structure orderly distribute among the octahedra space. The structural incorporation of 1D Aq-PbI3(II) perovskite inside 3D CsPbI2Br perovskite is proved to be capable of improving the carrier transport ability, whilst enhancing its hydrophobic performances, which is associated with the unique structure of 1D Aq-PbI3(II) and lattice-matching heterojunction in 1D–3D perovskite. Consequently, the as-fabricated 1D–3D hybrid CsPbI2Br perovskite solar cell allows to increase the device VOC by a factor of 12%, yielding a power conversion efficiency (PCE) as high as 16.1%. Equally importantly, the corresponding 1D–3D perovskite solar cells demonstrate remarkably high stability more than 1300 h in comparison to the control 3D CsPbI2Br perovskite solar cell. This study provides a new strategy for the rational structure design of 1D–3D hybrid perovskite with high PCE and stability.