Endogenous Redox-Sensitive UV Absorbers Enable Efficient and Stable Full Air-Processed Perovskite Solar Cells

Area of Science:

• Materials Science
• Photovoltaics
• Chemical Engineering

Background:

• Perovskite solar cells (PSCs) suffer from degradation under UV light, hindering commercialization.
• Instability under non-equilibrium conditions, particularly UV radiation, limits PSC operational lifetime.

Purpose of the Study:

• To enhance the efficiency and stability of PSCs against UV degradation.
• To introduce an endogenous, redox-sensitive UV absorber for improved perovskite material protection.

Main Methods:

• Incorporation of 2,2″-Thiobis-(4-tert-octylphenoxy)-butylamine nickel (TTOB) into the perovskite precursor solution.
• Fabrication of PSC devices entirely in ambient air conditions.
• Evaluation of device performance and stability under various environmental stressors (UV exposure, real-time storage, continuous illumination).

Main Results:

• The integrated TTOB demonstrated superior UV shielding and sustained chemical passivation for defect repair.
• Achieved a power conversion efficiency (PCE) of 25.24% in air-fabricated devices.
• Demonstrated significant stability improvements: 86% efficiency after 1,000 h UV exposure, 87% after 40 days storage, and >80% after 1430 h illumination.

Conclusions:

• The endogenous redox-sensitive UV absorber (TTOB) effectively enhances PSC efficiency and stability.
• This UV protection strategy shows transformative potential for large-scale perovskite photovoltaic applications in outdoor environments.
• Ambient air fabrication combined with TTOB integration offers a viable path for commercial PSC deployment.