The low-dimensional (LD) perovskites are proven to be capable of blocking moisture erosion and thereby improving the photovoltaic device stability. In this review, the low-dimensional (LD) perovskite materials are carefully summarized that are induced by A-position organic substituents, starting from the crystal microstructure and electronic structure of LD (2D, 1D, and 0D) perovskite materials with regulating dimensions, combined with first principles calculation (DFT). By further studying the thermodynamics and dynamics of crystallization nucleation and growth of LD-3D perovskite thin films in the heterojunction region, LD-3D heterojunction perovskite thin films and solar cells with controllable dimensions can be in situ prepared. Various LD-3D perovskite structure photovoltaic devices are systematically summarized, which shows flexible regulation of the energy band structure and carrier transport characteristics, locks the water oxygen corrosion channel with close-fitting conjugated structure, and improves the long-term stability of the LD-3D perovskite solar cells. This review is expected to provide some guidance for the perovskite development and multipurpose use through in depth understanding of the structurally dimensional engineering in perovskite photovoltaics.

The stability of perovskite solar cells has been identified as the bottleneck for their industrialization. With an aim at tackling this challenge, we self-synthesize a thus-far unreported linearly rotatable structure perovskite, i.e., TrMAPbX 3 (X = Br, I). The as-prepared hybrid perovskite is observed to demonstrate extremely high stability during device operation with high electric field strength and high temperature, which is associated with the good lattice-matching heterojunction structure between the linearly rotatable TrMAPbX 3 structure and 3D inorganic perovskite domain within a wide temperature range. The tight-fitting interface structure is devoted to inhibiting the accumulation of vacancy defects during device operation, which further avoids the δ-phase transition and charge transport resistance. Accordingly, we realize a CsPbI 3−x Br x inorganic perovskite-based solar cell with power conversion efficiency (PCE) of 20.59%, extending the remarkably high thermal stability to 192 h (85 °C and relative humidity of 25%) and 3055 h (25 °C and relative humidity of 25%).