Intermediate-phase engineering via dimethylammonium cation additive for stable perovskite solar cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Long-term stability of perovskite solar cells is a critical barrier to commercialization.
• Current dimethyl-formamide/dimethyl-sulfoxide methods yield poor perovskite film quality.
• Understanding crystallization's impact on device stability is essential.

Purpose of the Study:

• To develop a novel processing method for improved perovskite solar cell stability.
• To investigate the effect of a dimethylammonium chloride additive on perovskite crystallization.
• To enhance the operational lifetime of perovskite optoelectronic devices.

Main Methods:

• Introduced a high-temperature, dimethyl-sulfoxide-free processing technique.
• Utilized dimethylammonium chloride as an additive to control precursor phases.
• Tuned perovskite crystallization sequence, grain size, texturing, and orientation.

Main Results:

• Achieved improved crystal quality and microstructure in perovskite films.
• Formamidinium (FA)/caesium (FA)_yCs_1-yPb(I_xBr_1-x)₃ perovskite system showed enhanced properties.
• Encapsulated devices demonstrated improved operational stability with a median T80 lifetime of 1,190 hours.

Conclusions:

• Material quality is paramount for long-term operational stability in perovskite devices.
• The novel processing method significantly enhances perovskite solar cell performance and longevity.
• This approach offers a promising pathway for commercializing stable perovskite solar cells.