Stabilizing perovskite-substrate interfaces for high-performance perovskite modules

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Perovskite solar cells (PSCs) are promising for renewable energy.
• Interfacial engineering is crucial for PSC efficiency and stability.
• The perovskite-substrate interface is less studied than top interfaces.

Purpose of the Study:

• Investigate the impact of dimethyl sulfoxide (DMSO) on perovskite-substrate interfaces.
• Develop strategies to mitigate interfacial voids and improve PSC stability.
• Enhance the power conversion efficiency (PCE) and operational lifetime of PSCs.

Main Methods:

• Utilized dimethyl sulfoxide (DMSO) as a liquid additive for perovskite film formation.
• Introduced solid-state carbohydrazide to partially replace DMSO.
• Fabricated p-type/intrinsic/n-type (p-i-n) PSCs using blade coating.
• Conducted 550-hour operational stability tests at 60°C.

Main Results:

• DMSO was found to be trapped during film formation, creating voids at perovskite-substrate interfaces.
• These voids accelerated PSC degradation under illumination.
• Partial replacement of DMSO with carbohydrazide effectively reduced interfacial voids.
• Achieved a maximum stabilized PCE of 23.6% for optimized PSCs.
• Demonstrated no efficiency loss after 550 hours of testing at 60°C.
• Perovskite mini-modules achieved certified PCEs of 19.3% (18.1 cm²) and 19.2% (50.0 cm²).

Conclusions:

• Interfacial voids caused by trapped DMSO are detrimental to PSC stability.
• Carbohydrazide is an effective additive for reducing interfacial voids and enhancing PSC performance.
• The developed PSCs exhibit high efficiency and excellent long-term operational stability.