Crystal structure

SN2 reaction

Perovskite (structure)

Orthorhombic crystal system

Engineering

Chemical engineering

Optoelectronics

Nanotechnology

Organic chemistry

Crystallography

Tetragonal crystal system

Chemistry

Materials science

Inert

Journal of the American Chemical Society

Black orthorhombic (B-γ) CsSnI3 with reduced biotoxicity and environmental impact and excellent optoelectronic properties is being considered as a promising eco-friendly candidate for high-performing perovskite solar cells (PSCs). A major challenge in a large-scale implementation of CsSnI3 PSCs includes the rapid transformation of Sn2+ to Sn4+ (within a few minutes) under an ambient-air condition. Here, we demonstrate that ambient-air stable B-γ CsSnI3 PSCs can be fabricated by incorporating N,N′-methylenebis(acrylamide) (MBAA) into the perovskite layer and by using poly(3-hexylthiophene) as the hole transporting material. The lone electron pairs of −NH and −CO units of MBAA are designed to form coordination bonding with Sn2+ in the B-γ CsSnI3, resulting in a reduced defect (Sn4+) density and better stability under multiple conditions for the perovskite light absorber. After a modification, the highest power conversion efficiency (PCE) of 7.50% is documented under an ambient-air condition for the unencapsulat...

Ambient-Air-Stable Lead-Free CsSnI<sub>3</sub> Solar Cells with Greater than 7.5% Efficiency

Ambient-Air-Stable Lead-Free CsSnI3 Solar Cells with Greater than 7.5% Efficiency

Ambient-Air-Stable Lead-Free CsSnI₃ Solar Cells with Greater than 7.5% Efficiency