Planar heterojunction perovskite solar cells via vapor-assisted solution process

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Hybrid organic/inorganic perovskites, such as methylammonium lead iodide (CH3NH3PbI3), are emerging as efficient light absorbers for next-generation solar cells.
• Achieving high performance in perovskite photovoltaics requires precise control over thin-film morphology and properties.

Purpose of the Study:

• To demonstrate a low-temperature vapor-assisted solution process for fabricating high-quality perovskite thin films.
• To investigate the fabrication of perovskite films with enhanced surface coverage, reduced roughness, and microscale grain size.
• To achieve high power conversion efficiency in perovskite solar cells using the developed fabrication method.

Main Methods:

• A low-temperature vapor-assisted solution process was employed for perovskite thin-film deposition.
• Characterization of film properties including surface coverage, roughness, and grain size.
• Fabrication and efficiency testing of planar heterojunction solar cells utilizing the prepared perovskite films.

Main Results:

• Polycrystalline perovskite thin films with full surface coverage, minimal surface roughness, and microscale grains were successfully constructed.
• Solar cells fabricated with these films achieved a power conversion efficiency of 12.1%.
• This represents the highest efficiency reported for methylammonium lead iodide (CH3NH3PbI3) based planar heterojunction solar cells to date.

Conclusions:

• The developed low-temperature vapor-assisted solution process offers a simple and effective approach for perovskite film preparation.
• This method facilitates high reproducibility for both perovskite films and the resulting photovoltaic devices.
• The study provides insights into the kinetic and thermodynamic parameters governing perovskite film growth.