Low-dimensional perovskites (LDPs), composed of single or few inorganic octahedral layers separated by bulky organic cations, have emerged as a promising class of semiconductors combining superior environmental stability with highly tunable electronic properties. While their incorporation as passivation layers has significantly improved the performance and durability of three-dimensional (3D) perovskite solar cells, their broader potential as functional materials for photovoltaic applications remains largely unexplored. Recent advances revealing ferroelectric behavior, symmetry-driven phenomena, and controllable crystal orientation have opened new opportunities to exploit LDPs beyond their conventional role as interfacial stabilizers.

In this contribution, we present recent progress in the development of functional low-dimensional perovskites for next-generation solar cells. We first demonstrate how ferroelectric layered perovskites can be engineered at critical interfaces to promote directional charge separation and extraction. The intrinsic polarization of these materials generates local electric fields that facilitate carrier transport, suppress interfacial recombination, and improve device operational stability. We further discuss emerging approaches based on molecular design, including chiral organic spacers, to tailor interfacial charge-transfer processes and electronic interactions in layered perovskite heterostructures.

Beyond interface engineering, we address one of the key limitations hindering the direct implementation of LDPs as photoactive absorbers: inefficient out-of-plane charge transport. Conventional layered perovskites typically exhibit randomly oriented inorganic frameworks, creating energetic and structural barriers for vertical carrier extraction. To overcome this challenge, we develop a crystallographic engineering strategy that promotes preferential vertical alignment of the inorganic layers, establishing efficient charge-percolation pathways while preserving the intrinsic stability advantages of low-dimensional structures.

This approach enables a substantial enhancement in carrier transport and photovoltaic performance, leading to a record power conversion efficiency of 9.4% together with an open-circuit voltage approaching 1.4 V, among the highest values reported for low-dimensional perovskite solar cells. Advanced structural, spectroscopic, and optoelectronic investigations reveal a direct correlation between crystalline orientation, polarization effects, and charge-transport dynamics, providing fundamental insights into the mechanisms governing device operation.

Collectively, these results establish low-dimensional perovskites as a versatile platform for photovoltaic innovation. By combining ferroelectric functionality, rational molecular design, and controlled crystal growth, we introduce new strategies to manipulate charge generation, separation, and transport in layered semiconductors. These findings pave the way toward efficient and intrinsically stable photovoltaic technologies for emerging applications ranging from indoor energy harvesting and tandem solar cells to building-integrated photovoltaics and agrivoltaic systems.