Two-Dimensional Perovskite Solar Cells

Two-dimensional perovskite solar cells represent a class of photovoltaic devices in which inorganic metal halide layers are separated by organic spacer cations, forming a quantum-well structure. By contrast with three-dimensional perovskites, the reduced dimensionality confers enhanced environmental stability and moisture resistance, as bulky organic layers shield the reactive metal halide slabs. Charge transport in these materials is governed by the alignment of perovskite sheets: vertical orientation promotes efficient out-of-plane carrier extraction, while horizontal orientation can impede charge flow. Fine-tuning of quantum-well thickness, spacer chemistry and crystallisation kinetics allows control of the energy landscape, suppression of non-radiative recombination and optimisation of open-circuit voltage. Recent advances have explored mechanisms of nucleation at air-liquid interfaces, the impact of orientational degeneracy in spacer cations and routes to achieve a homogeneous energy landscape within mixed-phase films. Collectively, these insights are driving perovskite solar cells towards competitive efficiencies coupled with improved operational durability and scalability.

Research from Nature Portfolio

Recent studies have elucidated the mechanism by which two-dimensional perovskite layers adopt a vertical orientation during solution processing. It was revealed that nucleation often initiates at the liquid–air interface and that judicious choice of substrate leaves scope for polymeric or oxide supports without compromising alignment. Efforts to control the packing of organic spacer cations have demonstrated that selective fluorination and variation in molecular symmetry can modulate orientational degeneracy, altering formation energies and film properties to yield higher photocurrents. A further advance has addressed the inhomogeneous energy landscape inherent to mixed-phase quasi-2D systems: by combining density functional theory-guided design with kinetic regulation of crystallisation, a homogeneous energy distribution was realised, reducing Shockley–Read–Hall recombination and boosting open-circuit voltage.

Two-Dimensional Perovskite Solar Cells publication trend

The graph below shows the total number of articles in two-dimensional perovskite solar cells across all publications each year (not limited to Nature Index journals).

Technical terms

Perovskite: A crystal structure of the form ABX₃, where A and B are cations and X is an anion, often metal halide in photovoltaics.

Ruddlesden–Popper phase: A two-dimensional perovskite configuration featuring alternating inorganic layers and monovalent spacer cations.

Dion–Jacobson phase: A layered perovskite structure composed of divalent organic spacer cations sandwiched between inorganic slabs.

Quantum well: A nanoscale region where charge carriers are confined in one dimension by energy barriers, influencing electronic and optical properties.

Spacer cation: An organic molecule inserted between perovskite layers to control dimensionality, orientation and stability.

References

1. Additive Engineering for Stable and Efficient Dion–Jacobson Phase Perovskite Solar Cells. Nano-Micro Letters (2023).
2. Intermediate phase assisted sequential deposition of reverse‐graded quasi‐2D alternating cation perovskites for MA‐free perovskite solar cells. InfoMat (2023).
3. Origin of vertical orientation in two-dimensional metal halide perovskites and its effect on photovoltaic performance. Nature Communications (2018).
4. Synthetic control over orientational degeneracy of spacer cations enhances solar cell efficiency in two-dimensional perovskites. Nature Communications (2019).
5. Reduced-dimensional perovskite photovoltaics with homogeneous energy landscape. Nature Communications (2020).
6. Design principles for electronic charge transport in solution-processed vertically stacked 2D perovskite quantum wells. Nature Communications (2018).
7. Effective Phase‐Alignment for 2D Halide Perovskites Incorporating Symmetric Diammonium Ion for Photovoltaics. Advanced Science (2021).