Efficient Blade-Coated Wide-Bandgap Perovskite Solar Cells via Interface Engineering.

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• High-efficiency all-perovskite tandem solar cells often use a superstrate configuration, which is prone to degradation.
• The bottom narrow-bandgap subcells in superstrate designs are exposed to air, leading to oxidative instability.
• Substrate configurations offer enhanced stability by protecting the narrow-bandgap subcell.

Purpose of the Study:

• To develop a stable substrate-structured perovskite tandem solar cell.
• To overcome fabrication challenges of wide-bandgap perovskite solar cells on narrow-bandgap subcells in inert atmospheres.
• To improve the stability and efficiency of perovskite solar cells.

Main Methods:

• Developed a nonaqueous NiO nanoparticle dispersion for interlayer fabrication within a glove box.
• Utilized blade-coating for the NiO interlayer and formed a 2PACz monolayer hole transporting layer.
• Investigated the energetic alignment of 2PACz molecules to reduce recombination.

Main Results:

• Successfully fabricated a stable substrate-structured perovskite tandem solar cell.
• Achieved a densely packed NiO/2PACz hybrid hole transporting layer.
• Demonstrated reduced minority carrier recombination at the NiO/perovskite interface.
• Attained a champion power conversion efficiency of 17.4% for 1.77 eV wide-bandgap perovskite solar cells.

Conclusions:

• The nonaqueous NiO dispersion enables efficient fabrication of stable substrate-type perovskite tandem solar cells.
• The NiO/2PACz hybrid hole transporting layer enhances device performance by minimizing recombination.
• This approach offers a scalable pathway for developing more durable and efficient perovskite solar cells.