Constructing tin oxides Interfacial Layer with Gradient Compositions for Efficient Perovskite/Silicon Tandem Solar...

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Atomic layer deposition (ALD) of SnO_x films offers improved carrier-selective contacts and humidity resistance for perovskite solar cells.
• Current ALD-SnO_x processes face limitations due to perovskite material interactions, often requiring an additional fullerene layer.

Purpose of the Study:

• To develop an optimized ALD process for SnO_x buffer layers that minimizes perovskite degradation and enhances solar cell performance.
• To design a gradient SnO_x composition structure to improve carrier extraction and reduce reliance on fullerene layers.

Main Methods:

• Controlled ALD of SnO_x films with varying water doses to balance perovskite stability and electrical properties.
• Fabrication of a gradient SnO_x buffer layer by gradually increasing oxygen source during vapor deposition.
• Integration and testing of the gradient SnO_x layer in perovskite/silicon tandem solar cells with textured Czochralski silicon.

Main Results:

• Reducing water dose during SnO_x deposition minimized perovskite underlayer degradation.
• Increasing water dose improved the electrical properties of the SnO_x films.
• The gradient SnO_x structure enhanced carrier extraction, reducing the need for a fullerene layer.
• Achieved a certified efficiency of 28.0% for perovskite/silicon tandem cells (1.0 cm²).

Conclusions:

• A gradient SnO_x buffer layer fabricated via optimized ALD is effective for high-performance perovskite solar cells.
• This approach offers broad applicability across different perovskite compositions and textured morphologies.
• The developed method significantly boosts the efficiency of perovskite/silicon tandem solar cells.