Perovskite Solar Cell Interfacial Engineering Techniques

Perovskite solar cells have surged to the forefront of photovoltaic research owing to their remarkable power conversion efficiencies and low fabrication costs. Central to further progress is interfacial engineering, which addresses charge recombination, defect states and long-term stability at the boundaries between the perovskite absorber and charge‐transport layers. Strategies range from molecular passivation—using tailored organic or inorganic interlayers to neutralise surface traps—to compositional homogenisation within the perovskite film itself. Advances also include the design of charge‐selective contacts that align energy levels, the integration of p–n homojunctions in electron‐transport layers to boost carrier mobility and the refinement of self‐assembled monolayers to create conformal, lossless interfaces. Collectively, these approaches have pushed certified efficiencies beyond 25 % while enhancing thermal and operational stability, paving the way for scalable, commercial‐scale deployment of perovskite photovoltaics.

Research from Nature Portfolio

Recent studies have demonstrated that spatial uniformity of A-site cations can markedly improve film quality and device performance. One investigation utilised a phenylsulfonylpyrrole additive to homogenise the distribution of formamidinium and caesium ions throughout FA₁₋ₓCsₓPbI₃ films, suppressing vertical segregation and non-radiative recombination. Devices incorporating this approach achieved a certified steady-state efficiency of 25.2 % alongside enhanced operational stability. Another work introduced an ortho-carborane interlayer, decorated with phenylamino groups, at the perovskite/C₆₀ junction in inverted architectures. This three-dimensional aromatic molecule effectively passivates surface defects, eliminates interfacial recombination losses and functions as both electron transporter and hole blocker. The resulting cells deliver over 23 % efficiency and retain more than 97 % of initial performance after extended maximum power point operation.

Perovskite Solar Cell Interfacial Engineering Techniques publication trend

The graph below shows the total number of articles in perovskite solar cell interfacial engineering techniques across all publications each year (not limited to Nature Index journals).

Technical terms

Interfacial passivation: Treating the boundary between layers to neutralise defect sites and minimise non-radiative recombination.

Self-assembled monolayer (SAM): A densely packed, single-molecule-thick film formed spontaneously on a substrate to modify its surface energy and electronic properties.

Charge-selective contact: A functional interface that preferentially transports electrons or holes, thereby reducing carrier loss and improving open-circuit voltage.

Electron transport layer (ETL): A material layer designed to extract and transport electrons from the light-absorbing perovskite to the electrode with minimal resistance.

P–n homojunction: An engineered junction within a single semiconductor material containing p-type and n-type regions to enhance charge separation and mobility.

References

1. Homogenizing out-of-plane cation composition in perovskite solar cells. Nature (2023).
2. Overcoming C60-induced interfacial recombination in inverted perovskite solar cells by electron-transporting carborane. Nature Communications (2022).
3. TiO2 Electron Transport Layer with p–n Homojunctions for Efficient and Stable Perovskite Solar Cells. Nano-Micro Letters (2024).
4. Self‐assembled monolayers (SAMs) in inverted perovskite solar cells and their tandem photovoltaics application. Interdisciplinary Materials (2024).
5. Co‐Self‐Assembled Monolayers Modified NiOx for Stable Inverted Perovskite Solar Cells. Advanced Materials (2024).
6. Conformal monolayer contacts with lossless interfaces for perovskite single junction and monolithic tandem solar cells. Energy & Environmental Science (2019).