Intralayer bidentate diammoniums for stable two-dimensional perovskites

Area of Science:

• Materials Science
• Solid-State Chemistry
• Nanotechnology

Background:

• Two-dimensional (2D) metal halide perovskites are crucial for optoelectronics.
• Existing types include Ruddlesden-Popper (R-P) and Dion-Jacobson (D-J) phases.
• There is a need for enhanced structural diversity and stability in 2D perovskites.

Purpose of the Study:

• Introduce a novel class of 2D perovskites, termed B-D phase perovskites.
• Incorporate intralayer bidentate ligands to improve structural properties.
• Evaluate the stability and performance of these new perovskites for optoelectronic applications.

Main Methods:

• Synthesized bidentate ligands with rigid cores and ammonium-terminated linkers.
• Obtained single crystals of B-D phase perovskites with intralayer bidentate coordination.
• Conducted molecular dynamics simulations to assess ligand binding energies.
• Fabricated polycrystalline thin films and photovoltaic devices for performance testing.

Main Results:

• B-D phase perovskites demonstrated significantly stronger binding energies compared to R-P and D-J phases.
• Polycrystalline B-D phase films exhibited superior thermal resistance (1,600% and 140% improvement over R-P and D-J, respectively).
• Photovoltaic devices utilizing B-D ligands showed higher power conversion efficiency and improved operational stability.

Conclusions:

• B-D phase 2D perovskites represent a promising new platform for advanced optoelectronic devices.
• Ligand engineering with intralayer bidentate coordination enhances structural diversity and material stability.
• This work advances the field of metal halide perovskites and hybrid materials for next-generation technologies.