Unraveling a Structure-Property Relationship for Methylammonium Lead/Tin Trihalide Organic-Inorganic Hybrid Perovskite Solar Cells

TL;DR

This study uncovers a fundamental structure-property relationship in methylammonium lead/tin trihalide hybrid perovskites, linking hydrogen bonding distances to optical bandgaps, which informs material design for solar cells.

Contribution

It establishes a unified relationship between hydrogen bonding interactions and optical properties across lead and tin-based perovskite series, advancing understanding of organic cation roles.

Findings

Hydrogen bonding distance correlates with optical bandgap.

The relationship applies to both lead and tin perovskite series.

Hydrogen bonding influences optoelectronic functionality.

Abstract

The esoteric importance of intermolecular hydrogen bonding interaction to design novel methylammonium trihalide organic-inorganic hybrid perovskite solar cell materials is uncovered, establishing the unified structure-property relationship between the calculated Y...H intermolecular hydrogen bonding distance and the experimentally reported onset of optical absorption (bandgap) for the bulk geometries of the ten-membered methylammonium lead trihalide (CH3NH3PbY3) perovskite solar cell series, where Y = X (X = Cl, Br, I) and the mixed halogen derivatives. The same relationship is also revealed for the ten-membered methylammonium tin trihalide (CH3NH3SnY3) perovskite solar cell series. The relationship unequivocally demonstrates that the intermolecular hydrogen bonding interaction does not only enforce the aforesaid materials to become functional for optoelectronic application, but also serve as an asset to partially address the often debated question what is the role played by the CH3NH3+ organic cation.