Spatial confinement growth of perovskite nanocrystals for ultra-flexible solar cells

Abstract

State-of-the-art flexible perovskite solar cells (PSCs) are generally built on conductive plastic substrates, but they are limited to bending strain effects. We present here the spatial confinement growth of (6-ACA)_0.038(CH₃NH₃)_0.962PbI₃ nanocrystals from a solvothermal-processed precusor for ultra-flexible PSCs made in a three-dimensional gel framework. Our focus is placed on systematic studies of photovoltaic behavior at arbitrary deformations. The optimized PSC yields a photoelectric conversion efficiency of 0.88% in the undeformed state, and it increases to 2.51% at a bending angle of 120°, to 3.04% at an elongation of 180%, to 2.35% at a twist angle of 360°, and to 1.79% at a compression ratio of 30%. The PSC demonstrates enhanced photovoltaic performance when suffering repeated deformations and remains 82.1% efficient when exposed in 70%-humidity ambient air over 120 h.