Strain Engineering in Perovskite Solar Cells

Strain engineering has emerged as a pivotal strategy to optimise both efficiency and operational stability of perovskite solar cells. Mechanical stress—whether tensile or compressive—arises during film formation, thermal annealing and encapsulation, leading to lattice distortions that affect carrier dynamics, defect formation and moisture susceptibility. By deliberately introducing or compensating residual strain through interface layers, additives or tailored charge‐transport materials, researchers can modulate the perovskite crystal structure, suppress ion migration and reduce nonradiative recombination. These advances not only boost power conversion efficiencies but also address the long‐standing challenge of device longevity, accelerating the path towards commercialisation of perovskite photovoltaics.

Research from Nature Portfolio

Recent studies have revealed the significance of intentionally managed strain profiles in advanced device architectures. A 2024 investigation into thick‐film perovskite devices demonstrated that, once carrier‐lifetime limitations are removed, residual lattice strain becomes the primary performance bottleneck in films of micrometre scale. By mapping strain distributions and correlating them with efficiency losses, this work provides a blueprint for strain‐tolerant large‐area modules. A 2023 report introduced a long‐chain anionic surfactant additive that self‐assembles into a glue‐like scaffold at grain boundaries, effectively neutralising residual stress. The result is reduced defect density, suppressed ion migration and remarkable operational stability in both single‐junction and tandem cells under continuous illumination. Earlier in 2022, depth‐resolved wide‐angle X-ray scattering was applied to unmask complex strain heterogeneities through the film thickness. It was shown that tensile strain at the top surface accelerates moisture‐induced degradation at grain boundaries, guiding the refinement of deposition protocols to achieve more uniform stress distributions.

Strain Engineering in Perovskite Solar Cells publication trend

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

Technical terms

Residual strain: Internal stress retained in the perovskite lattice after processing, arising from thermal or mechanical mismatch.

Compressive strain: Stress that shortens lattice parameters, often used to inhibit ion migration and improve stability.

Tensile strain: Stress that stretches the lattice, which can promote defect formation and accelerate degradation.

Grain boundary: The interface between crystalline domains in polycrystalline films where strain concentrates and nonradiative recombination can increase.

Ion migration: Movement of ionic species under electric field or mechanical stress, leading to hysteresis and long-term instability in perovskite devices.

References

1. Strain regulates the photovoltaic performance of thick-film perovskites. Nature Communications (2024).
2. Long-chain anionic surfactants enabling stable perovskite/silicon tandems with greatly suppressed stress corrosion. Nature Communications (2023).
3. Mapping structure heterogeneities and visualizing moisture degradation of perovskite films with nano-focus WAXS. Nature Communications (2022).
4. Stress compensation based on interfacial nanostructures for stable perovskite solar cells. Interdisciplinary Materials (2023).
5. Stretchable alkenamides terminated Ti3C2Tx MXenes to release strain for lattice‐stable mixed‐halide perovskite solar cells with suppressed halide segregation. Carbon Energy (2023).
6. Strain effects on halide perovskite solar cells. Chemical Society Reviews (2022).