Aryl-Acetylene Layered Hybrid Perovskites in Photovoltaics

Area of Science:

• Materials Science
• Solid-State Chemistry
• Photovoltaics

Background:

• Metal halide perovskites show promise for solar energy conversion but suffer from poor operational stability.
• Two-dimensional (2D) halide perovskites with hydrophobic organic spacers offer improved stability but often have insulating spacers that limit functionality.
• Extending π-conjugation in organic spacers can potentially overcome charge confinement issues.

Purpose of the Study:

• To synthesize and characterize novel 2D perovskites incorporating aryl-acetylene-based organic spacers with extended π-conjugation.
• To investigate the opto(electro)ionic properties of these new materials.
• To evaluate their performance in mixed-dimensional perovskite solar cells.

Main Methods:

• Synthesis of Ruddlesden-Popper and Dion-Jacobson 2D perovskites using (4-ethynylphenyl)methylammonium (BMAA) and buta-1,3-diyne-1,4-diylbis(4,1-phenylene)dimethylammonium (BDAA) spacers.
• Characterization of opto(electro)ionic properties using various techniques.
• Fabrication and testing of mixed-dimensional perovskite solar cells.

Main Results:

• Successfully synthesized 2D perovskites with novel aryl-acetylene-based spacers (BMAA and BDAA).
• Demonstrated enhanced opto(electro)ionic characteristics due to extended π-conjugation.
• Achieved superior device performance in mixed-dimensional perovskite solar cells, reaching power conversion efficiencies up to 23% with improved operational stability.

Conclusions:

• Aryl-acetylene-based spacers enable the development of highly stable and efficient 2D perovskite solar cells.
• Extended π-conjugation in spacers is crucial for overcoming charge confinement and enhancing functionality.
• These findings open new avenues for multifunctional layered hybrid materials in photovoltaics.