Atomic Layer Deposited Tin Oxide Buffer Layer via Layer-by-layer Growth for Efficient Semitransparent Perovskite...

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Atomic layer deposition (ALD) of tin oxide (SnO2) is vital for high-performance semitransparent perovskite solar cells (ST-PSCs) and perovskite/silicon tandem solar cells.
• Low substrate reactivity in ALD can lead to island growth, pinholes, and degraded device performance.

Purpose of the Study:

• To develop a simple method for fabricating dense and uniform ALD SnO2 buffer layers.
• To improve the performance and stability of ST-PSCs and tandem solar cells by optimizing the ALD SnO2 layer.

Main Methods:

• Activated substrate nucleation by reversing the ALD precursor introduction sequence (oxygen precursor first).
• Fabricated ST-PSCs and perovskite/silicon tandem solar cells using the optimized ALD SnO2 buffer layer.
• Evaluated device performance (power conversion efficiency) and stability (moisture and thermal).

Main Results:

• The modified ALD process transformed island-like growth to layer-by-layer growth, yielding dense, vertically uniform SnO2 films.
• ST-PSCs showed an increased initial power conversion efficiency (PCE) from 19.37% to 19.99% (3.2% improvement).
• Perovskite/silicon tandem solar cells achieved a PCE of 28.77%.
• ST-PSCs demonstrated enhanced stability, retaining 96.6% and 95.6% of initial PCE after 600h of humidity and thermal stress, respectively.

Conclusions:

• A simple precursor sequence adjustment effectively creates dense ALD SnO2 buffer layers.
• This method significantly improves the performance and stability of ST-PSCs and tandem solar cells.
• The optimized ALD SnO2 layers show potential for various optoelectrical devices.