Low-dimensional perovskites (LDPs), consisting of single or few inorganic octahedral layers separated by bulky organic cations, have emerged as a promising class of semiconductors owing to their superior environmental and structural stability compared to conventional three-dimensional (3D) perovskites. Their exceptional robustness has enabled widespread adoption as interfacial passivation layers in high-performance perovskite solar cells. However, their direct implementation as photoactive absorbers remains largely unexplored due to their intrinsically wide bandgap, disordered morphology, and inefficient out-of-plane charge transport, which severely limit photovoltaic performance.

In this contribution, we present recent advances in the design and implementation of low-dimensional perovskites for next-generation photovoltaic applications. First, we demonstrate how ferroelectric low-dimensional perovskites can be strategically integrated at interfaces to enhance charge extraction and suppress interfacial recombination in highly efficient perovskite solar cells. The intrinsic polarization of these materials promotes directional charge separation, resulting in improved carrier collection and device operation.

Beyond their role as interfacial modifiers, we introduce a crystallographic engineering strategy that enables low-dimensional perovskites to function as efficient active layers. By controlling nucleation and crystal growth, we induce preferential vertical alignment of the inorganic framework, effectively overcoming the major transport bottleneck associated with conventional randomly oriented LDP films. This approach establishes efficient vertical charge percolation pathways while preserving the intrinsic stability advantages of low-dimensional structures.

As a result, we achieve a record power conversion efficiency of 9.4% together with an open-circuit voltage of 1.4 V, among the highest values reported for low-dimensional perovskite solar cells. Advanced structural and optoelectronic characterization reveals a direct correlation between crystalline orientation, carrier transport dynamics, and photovoltaic performance, highlighting the critical importance of orientational control in these materials.

These findings demonstrate that low-dimensional perovskites can evolve from passive interfacial components into efficient photoactive semiconductors. The presented strategies provide a general framework for overcoming transport limitations in layered perovskites and open new opportunities for stable wide-bandgap photovoltaics targeting emerging applications including indoor energy harvesting, building-integrated photovoltaics, tandem devices, and agrivoltaic systems.