Solution-Processed Multivalent Molybdenum Oxide Tailoring Band Alignment for Efficient Sb₂S₃ Solar Cells.

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Antimony sulfide (Sb₂S₃) shows promise for solar cells due to its photoelectric properties.
• Conventional hole transport layers (HTLs) like Spiro-OMeTAD and PbS present stability and toxicity issues.
• Developing stable, eco-friendly HTLs is crucial for advancing Sb₂S₃ solar cell technology.

Purpose of the Study:

• To develop a cost-effective, eco-friendly, and non-toxic hole transport layer (HTL) for Sb₂S₃ solar cells.
• To improve the performance and stability of Sb₂S₃ solar cells by addressing back-contact recombination.
• To investigate the use of molybdenum oxide (MoO_x) as a novel HTL in Sb₂S₃ photovoltaic devices.

Main Methods:

• Fabrication of a solution-processed molybdenum oxide (MoO_x) hole transport layer (HTL).
• Incorporation of sodium ascorbate into the MoO_x precursor to modulate molybdenum valence states and energy levels.
• Characterization of Sb₂S₃ solar cells with the novel MoO_x HTL, including J-V curve analysis.

Main Results:

• The MoO_x HTL significantly improved Sb₂S₃ solar cell efficiency from 0.36% to 4.47%.
• The fill factor increased from 15.37% to 53.00% with the introduction of the MoO_x HTL.
• The addition of sodium ascorbate effectively addressed the roll-over effect in J-V curves by optimizing band alignment and hole extraction.

Conclusions:

• Molybdenum oxide (MoO_x) serves as a high-performance, green, and stable HTL for Sb₂S₃ solar cells.
• This work presents a significant advancement in developing non-toxic and efficient Sb₂S₃-based photovoltaic devices.
• The findings offer valuable insights for the future design of sustainable and high-performance solar cell technologies.