Homogeneous crystallization and buried interface passivation for perovskite tandem solar modules

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Scalable fabrication of all-perovskite tandem solar cells is hindered by challenges in narrow-bandgap subcells, specifically mixed lead-tin (Pb-Sn) perovskite films.
• Issues include nonuniform crystallization and poor buried perovskite interfaces, limiting device performance and manufacturability.

Purpose of the Study:

• To address the challenges in scalable fabrication of all-perovskite tandem solar cells.
• To improve the crystallization and interface quality of mixed lead-tin (Pb-Sn) perovskite films for narrow-bandgap subcells.

Main Methods:

• Utilized aminoacetamide hydrochloride, a dopant from Good's list of biochemical buffers, to homogenize perovskite crystallization.
• Applied the dopant to extend the processing window for blade-coating Pb-Sn perovskite films.
• Employed the dopant for selective passivation of defects at the buried perovskite interface.

Main Results:

• Achieved homogenized perovskite crystallization in Pb-Sn films.
• Extended the processing window for blade-coating, enabling more uniform film deposition.
• Successfully passivated defects at the buried perovskite interface, enhancing charge transport.
• Fabricated an all-perovskite tandem solar module with a certified power conversion efficiency of 24.5%.

Conclusions:

• Aminoacetamide hydrochloride is an effective dopant for improving the quality and processability of Pb-Sn perovskite films.
• The developed method enables scalable fabrication of high-efficiency all-perovskite tandem solar cells.
• The 24.5% certified efficiency demonstrates the potential of this approach for next-generation solar energy technologies.