Making Perovskite Photo voltaic Cells Extra Steady

Perovskite photo voltaic cells are reasonably priced and work effectively however don’t final. A brand new methodology fixes this drawback with out frequent trade-offs. What makes it totally different?

Perovskite photo voltaic cells could be a low-cost and environment friendly strategy to produce vitality, however they’ve a giant drawback—they don’t final lengthy. Perovskite photo voltaic cells could be a low-cost and environment friendly strategy to produce vitality, however they’ve a giant drawback—they don’t final lengthy. A analysis group from Peking College has printed two papers on perovskite photo voltaic cells in Science.

Because of its photovoltaic properties, low price, and thermal stability, formamidinium lead triiodide (FAPbI₃) is a promising absorber for high-efficiency single-junction perovskite photo voltaic cells. Nonetheless, its advanced crystallization kinetics and thermodynamic metastability at room temperature problem crystallization high quality and long-term stability.

Alloying methods, comparable to including methylammonium hydrochloride and Cs⁺, assist management crystallization and enhance photoelectric properties. Nonetheless, they typically go away residual components that may result in cation-anion separation, thermal decomposition, and undesirable chemical reactions.

These challenges make producing high-quality, non-alloyed α-FAPbI₃/perovskite movies and associated units tough. The group have launched an iodine intercalation-declaration technique to supply high-quality, unalloyed α-FAPbI₃ perovskite movies, enhancing the effectivity and stability of perovskite photo voltaic cells.

On this method, the sturdy interplay between cogenetic iodine (I₂) and I⁻ varieties polyiodide ions, altering the traditional FAI + PbI₂ → FAPbI₃ response path to FAI₃ + PbI₂ → FAPbI₃ + I₂. This modification helps overcome limitations to α-FAPbI₃ formation.

Throughout annealing, the volatility of I₂ ensures its full removing from the lattice, stopping extrinsic residue and leading to a high-quality, nonalloyed α-FAPbI₃ movie. The improved crystal high quality and uniformity improve thermal stability, decreasing ion migration.

Photo voltaic cells primarily based on this nonalloyed α-FAPbI₃ movie achieved an influence conversion effectivity of over 24% and retained 99% of their unique effectivity after greater than 1,100 hours of operation at 85°C underneath illumination. This work highlights the group’s contributions to advancing photovoltaic expertise by addressing key challenges in stability and effectivity.

References: Yu Zhang et al, Nonalloyed α-phase formamidinium lead triiodide photo voltaic cells by way of iodine intercalation, Science (2025). DOI: 10.1126/science.ads8968

Huachao Zai et al, Wafer-scale monolayer MoS 2 movie integration for steady, environment friendly perovskite photo voltaic cells, Science (2025). DOI: 10.1126/science.ado2351