Co-La-Based Hole-Transporting Layers for Binary Organic Solar Cells with 18.82 % Efficiency.

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is a common hole transporting layer (HTL) in organic solar cells (OSCs).
• The inherent acidity of PEDOT:PSS significantly compromises the long-term stability and performance of OSC devices.
• There is a critical need for alternative HTLs that offer improved stability and efficiency.

Purpose of the Study:

• To introduce and evaluate a novel cobalt-lanthanum (Co-La) inorganic system as a hole transporting layer (HTL) for organic solar cells (OSCs).
• To investigate the charge transfer complex formation between cobalt and lanthanum atoms and its effect on material properties.
• To demonstrate the potential of the Co-La system to replace PEDOT:PSS for stable and high-performance OSCs.

Main Methods:

• Fabrication of organic solar cells (OSCs) utilizing the synthesized Co-La inorganic system as the HTL.
• Characterization of the Co-La system's electronic properties, including work function and conductivity.
• Performance evaluation of the OSCs, focusing on power conversion efficiency (PCE) and device stability.

Main Results:

• The Co-La HTL achieved a high power conversion efficiency (PCE) of 18.82%, positioning it among the top-performing binary systems in OSCs.
• The interaction between electron-rich lanthanum and cobalt atoms formed a charge transfer complex, enhancing both work function and conductivity.
• The Co-La system demonstrated superior performance when applied to various OSC architectures, indicating broad applicability.

Conclusions:

• The binary Co-La inorganic system presents a promising alternative to PEDOT:PSS for hole transport in OSCs.
• This novel HTL effectively addresses the stability issues associated with PEDOT:PSS, paving the way for more durable and efficient organic solar cells.
• The Co-La system exhibits significant potential for widespread application in the field of organic photovoltaics.