Buried Interlayer Induced 1D Perovskite Seeds Enable Over 31%-Efficiency Perovskite/TOPCon Tandem Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Solid-State Physics

Background:

• Wide-bandgap perovskite films are crucial for high-efficiency solar cells.
• Controlling perovskite crystallization at buried interfaces is key for device performance and stability.
• 1D perovskite engineering offers a promising strategy for interface optimization.

Purpose of the Study:

• To investigate the use of 1D perovskite formation at buried interfaces to regulate crystallization.
• To enhance the efficiency and stability of perovskite/TOPCon tandem solar cells.
• To introduce Tetra-n-butylammonium dichlorobromide (TBADCB) for controlled 1D perovskite nucleation.

Main Methods:

• Introduction of TBADCB at the buried interface to promote preferential 1D perovskite formation.
• Utilizing 1D perovskite seeds for bottom-to-top crystallization of FA-based perovskite under solvent annealing.
• Characterization of crystal growth, interface properties, and device performance.

Main Results:

• TBADCB facilitated the formation of 1D perovskite seeds below the phase transition temperature.
• Improved crystallization led to enhanced open-circuit voltage (V_OC) and fill factor (FF) in single-junction cells (PCE 21.45%).
• Perovskite/TOPCon tandem cells achieved a certified efficiency exceeding 31%, with 80% initial efficiency retained after 700h of continuous illumination.

Conclusions:

• 1D perovskite engineering at buried interfaces is an effective strategy for improving perovskite solar cell performance.
• TBADCB acts as a nucleation agent, promoting controlled crystallization and reducing stress.
• The developed method significantly boosts the efficiency and stability of perovskite/TOPCon tandem solar cells.