Long-chain anionic surfactants enabling stable perovskite/silicon tandems with greatly suppressed stress corrosion

Abstract

Despite the remarkable rise in the efficiency of perovskite-based solar cells, the stress-induced intrinsic instability of perovskite active layers is widely identified as a critical hurdle for upcoming commercialization. Herein, a long-alkyl-chain anionic surfactant additive is introduced to chemically ameliorate the perovskite crystallization kinetics via surface segregation and micellization, and physically construct a glue-like scaffold to eliminate the residual stresses. As a result, benefiting from the reduced defects, suppressed ion migration and improved energy level alignment, the corresponding unencapsulated perovskite single-junction and perovskite/silicon tandem devices exhibit impressive operational stability with 85.7% and 93.6% of their performance after 3000 h and 450 h at maximum power point tracking under continuous light illumination, providing one of the best stabilities to date under similar test conditions, respectively.

The synergistic effect of dry air and surfactants enables water to be a promising green solvent for stable and efficient perovskite solar cells

“…Long-alkyl chains are linked with each other, physically connecting adjacent grains together to produce a softening effect. 37 The tight contact between grains contributes to maintaining the film integrity under stress. Furthermore, to study the residual strain in the perovskite film, grazing incident X-ray diffraction (GIXRD) is performed using the classical 2 θ − sin 2 ( ψ ) method, where θ and ψ represent the diffraction and tilt angles, respectively.…”

A dual passivation strategy based on F/N co-doped coal-based graphene quantum dots for high-efficiency carbon-based perovskite solar cells

“…The Fermi energy levels ( E F ) of the three kinds of perovskite films are up-shifted by 60 meV, 110 meV, and 150 meV in the in situ , post and dual films relative to that of the pristine, respectively, indicating that the surface energy levels of the three kinds of perovskite films are all n -type doped after passivation treatment. 29 At the same time, EF up-shift can increase the built-in potential ( V bi ) of the device, which will increase the driving force for separation of photo-generated carriers and V oc . 30 This is also the most important reason for the increase of the V oc of the device.…”

Molecular dipole engineering-assisted strain release for mechanically robust flexible perovskite solar cells

“…These results indicate that the mechanical strength of perovskite films can be decreased by modifying carbonitrile additives. 39…”