Architecturing 1D-2D-3D Multidimensional Coupled CsPbI2Br Perovskites toward Highly Effective and Stable Solar Cells

作者：Liu, Kun; Yuan, Songyang; Xian, Yeming; Long, Yi; Yao, Qin; Rahman, Naveed Ur; Guo, Yang; Sun, Mingyuan; Xue, Qifan; Yip, Hin-Lap; Cabot, Andreu; Li, Wenzhe^*; Fan, Jiandong^*

来源：Small, 2021, 17(25): 2100888.

DOI：10.1002/smll.202100888

• carrier transport
• CsPbI
• Br-2 perovskite solar cells
• heterojunctions
• stability
• strain relaxation

Despite the rapid development of CsPbIxBr3-x (0 <= x <= 3) inorganic perovskite solar cells, associated with their superior thermal stability, their low moisture stability limits their commercial deployment. In this study, 1D-2D-3D multidimensional coupled perovskites are prepared by means of an in situ self-integration approach. This pioneering method allows incorporating thus far unreported 1D-Tpy(2)Pb(3)I(6) and 2D-TpyPb(3)I(6) (Tpy; terpyridine) perovskites. Heterojunction perovskites demonstrate superior stability against water in comparison with control 3D CsPbI2Br, which is related to the hydrophobicity of low-dimension (LD) perovskites. Remarkably, the spontaneous involvement of LD perovskites can adjust/reconstruct the interfacial structure. This modification allows releasing the residual strain, establishing effective charge transfer channels that increase the carrier transport ability. Accordingly, 1D-2D-3D hybrid CsPbI2Br perovskite solar cells demonstrate a stabilized power conversion efficiency as high as 16.1%, which represents a very significant improvement, by a factor of 43%, with respect to control 3D CsPbI2Br perovskite solar cell. Equally importantly, the multidimensional coupled perovskite solar cells exhibit extraordinary stability, well above 1000 h in ambient atmosphere.