Light-induced lattice expansion leads to high-efficiency perovskite solar cells

Hsinhan Tsai (1) , Reza Asadpour (2) , Jean-Christophe Blancon (1) , Constantinos C Stoumpos (3) , Olivier Durand (4) , Joseph Strzalka (5) , Bo Chen (6) , Rafael Verduzco (6) , Pulickel M Ajayan (6) , Sergei Tretiak (1) , Jacky Even (4) , Muhammad A Alam (2) , Mercouri G Kanatzidis (3) , Wanyi Nie (1) , Aditya D Mohite (1)

1 LANL - Los Alamos National Laboratory
2 Purdue University [West Lafayette]
3 Northwestern University [Evanston]
4 FOTON - Institut des Fonctions Optiques pour les Technologies de l'informatiON
5 ANL - Argonne National Laboratory [Lemont]
6 Rice University [Houston]

Light-induced structural dynamics plays a vital role in the physical properties, device performance, and stability of hybrid perovskite–based optoelectronic devices. We report that continuous light illumination leads to a uniform lattice expansion in hybrid perovskite thin films, which is critical for obtaining high-efficiency photovoltaic devices. Correlated, in situ structural and device characterizations reveal that light-induced lattice expansion benefits the performances of a mixed-cation pure-halide planar device, boosting the power conversion efficiency from 18.5 to 20.5%. The lattice expansion leads to the relaxation of local lattice strain, which lowers the energetic barriers at the perovskite-contact interfaces, thus improving the open circuit voltage and fill factor. The light-induced lattice expansion did not compromise the stability of these high-efficiency photovoltaic devices under continuous operation at full-spectrum 1-sun (100 milliwatts per square centimeter) illumination for more than 1500 hours.

Domaines: Physique [physics]; Chimie

Hsinhan Tsai, Reza Asadpour, Jean-Christophe Blancon, Constantinos C Stoumpos, Olivier Durand, et al.. Light-induced lattice expansion leads to high-efficiency perovskite solar cells. Science, 2018, 360 (6384), pp.67-70. ⟨10.1126/science.aap8671⟩. ⟨hal-01760080⟩