Achieving over 20% efficiency in HTL-free carbon-electrode perovskite solar cells via multifunctional surface...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Perovskite solar cells (PSCs) are promising renewable energy sources.
• Developing efficient and stable PSCs, especially those using carbon electrodes (C-PSCs), is crucial for commercialization.
• Hole-transport-layer-free (HTM-free) architectures simplify device fabrication and reduce costs.

Purpose of the Study:

• To investigate the use of Ytterbium(III) triflate (Yb(TFSI)3) as a post-treatment additive in HTM-free C-PSCs.
• To enhance the performance and stability of C-PSCs by addressing surface defects and improving moisture resistance.
• To achieve high power conversion efficiencies (PCE) in C-PSCs.

Main Methods:

• Yb(TFSI)3 was applied as a post-treatment to perovskite films.
• Characterization of perovskite films and solar cell devices.
• Performance evaluation including power conversion efficiency (PCE) measurements.
• Assessment of device stability and moisture resistance.

Main Results:

• Yb(TFSI)3 effectively passivates surface defects in perovskite films.
• The additive optimizes interfacial energy levels, facilitating charge extraction.
• Enhanced moisture resistance was observed in the treated perovskite solar cells.
• The optimized C-PSCs achieved a highest power conversion efficiency (PCE) of 20.26%.

Conclusions:

• Yb(TFSI)3 is a multifunctional additive for improving HTM-free C-PSCs.
• The post-treatment strategy significantly enhances device performance and stability.
• Achieving over 20% PCE in C-PSCs demonstrates the potential of this approach for efficient solar energy conversion.