Stabilizing all-inorganic CsPbI₃ perovskite films with polyacrylonitrile for photovoltaic solar cells

Abstract

A solution-processed CsPbI3 perovskite film usually suffers from nonuniform crystallization owing to its inorganic components, leading to poor surface morphology and various defects on the surface and grain boundaries. Herein,...

Vacuum‐Assisted Thermal Annealing of CsPbI3for Highly Stable and Efficient Inorganic Perovskite Solar Cells

“…Moreover, the inside pinholes could provide the channels for moisture invasion and cause phase transformation from the black perovskite phase to the yellow non‐perovskite phase, affecting the stability of the resultant devices. As such, various additives were employed in the precursor solution to adjust the perovskite crystallization [32–36] . For instance, Liu's group recently reported a molten‐salt‐assisted crystallization (MSAC) strategy for improving grain growth of the CsPbI 3 perovskite films [32] .…”

Vacuum‐Assisted Thermal Annealing of CsPbI3for Highly Stable and Efficient Inorganic Perovskite Solar Cells

“…Moreover, the inside pinholes could provide the channels for moisture invasion and cause phase transformation from the black perovskite phase to the yellow non‐perovskite phase, affecting the stability of the resultant devices. As such, various additives were employed in the precursor solution to adjust the perovskite crystallization [32–36] . For instance, Liu's group recently reported a molten‐salt‐assisted crystallization (MSAC) strategy for improving grain growth of the CsPbI 3 perovskite films [32] .…”

“…As such, various additives were employed in the precursor solution to adjust the perovskite crystallization. [32][33][34][35][36] For instance, Liu's group recently reported a molten-salt-assisted crystallization (MSAC) strategy for improving grain growth of the CsPbI 3 perovskite films. [32] The MSAC promoted intensive mass transfer in the present of the fluent liquid medium, yielding high-quality CsPbI 3 perovskite films with suppressed pinhole and crack formation.…”

Organic Molecules in All‐Inorganic CsPbIxBr3−xPerovskite Solar Cells: Interface Modifiers or Precursor Additives

“…[ 135 ] Polyacrylonitrile (PAN) was used as a defect passivator for CsPbI 3 perovskite films, in which the lone pair of electrons of the N atom of the side chain backbone of the nitrile (C=N) functional group may passivate the uncoordinated Pb 2+ with a partial positive charge, reduce the defect density, and improve the energy barrier of the phase transition. [ 136 ] In addition, the addition of PAN raised the nucleation of the perovskite precursor to form dense CsPbI 3 perovskite film and enhance the heat and water resistance. A small amount of sulfobetaine zwitterions was introduced into the CsPbI 3 precursor solution to stabilize the α‐phase CsPbI 3 films at room temperature.…”