A Eu ³⁺ -Eu ²⁺ ion redox shuttle imparts operational durability to Pb-I perovskite solar cells

TLDR

Perovskite solar cells suffer from degradation due to oxygen, water, light, electric‑field, and thermal stresses, making device longevity a critical challenge that encapsulation alone cannot fully address. The authors introduce a Eu³⁺/Eu²⁺ redox shuttle that transfers electrons to regenerate Pb²⁺ and I⁻ ions in the lead‑iodine system. Devices using this shuttle retained over 90 % of their initial power‑conversion efficiency across multiple aging tests. Published in Science, p.

Abstract

A redox road to recovery Device longevity is a key issue for organic-inorganic perovskite solar cells. Encapsulation can limit degradation arising from reactions with oxygen and water, but light, electric-field, and thermal stresses can lead to metastable elemental lead and halide atom defects. Wang et al. show that for the lead-iodine system, the introduction of the rare earth europium ion pair Eu 3+ -Eu 2+ can shuttle electrons and recover lead and iodine ions (Pb 2+ and I − ). Devices incorporating this redox shuttle maintained more than 90% of their initial power conversion efficiencies under various aging conditions. Science , this issue p. 265