Supramolecular chemistry

Engineering

Ecology

Biology

Materials science

Layer (electronics)

Density functional theory

Formamidinium

Molecule

Perovskite (structure)

Chemical engineering

Nanotechnology

Organic chemistry

Computational chemistry

Chemistry

Crown ether

Photovoltaic system

Passivation

Journal of the American Chemical Society

The use of molecular modulators to reduce the defect density at the surface and grain boundaries of perovskite materials has been demonstrated to be an effective approach to enhance the photovoltaic performance and device stability of perovskite solar cells. Herein, we employ crown ethers to modulate perovskite films, affording passivation of undercoordinated surface defects. This interaction has been elucidated by solid-state nuclear magnetic resonance and density functional theory calculations. The crown ether hosts induce the formation of host-guest complexes on the surface of the perovskite films, which reduces the concentration of surface electronic defects and suppresses nonradiative recombination by 40%, while minimizing moisture permeation. As a result, we achieved substantially improved photovoltaic performance with power conversion efficiencies exceeding 23%, accompanied by enhanced stability under ambient and operational conditions. This work opens a new avenue to improve the performance and stability of perovskite-based optoelectronic devices through supramolecular chemistry.

Crown Ether Modulation Enables over 23% Efficient Formamidinium-Based Perovskite Solar Cells