Solid-state dye-sensitized solar cells based on ZnO nanocrystals.

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Dye-sensitized solar cells (DSSCs) are a promising photovoltaic technology.
• Zinc oxide (ZnO) offers potential as a cost-effective alternative to traditional TiO2 photoanodes.
• Solution-processed fabrication methods are crucial for scalable and economical DSSC production.

Purpose of the Study:

• To develop and optimize solution-processed ZnO-based dye-sensitized solar cells.
• To investigate the impact of precursor formulation and sintering on ZnO electrode morphology and device performance.
• To enhance dye loading and charge dynamics in ZnO DSSCs.

Main Methods:

• Fabrication of mesoporous ZnO electrodes via sol-gel processing of ZnO nanorods.
• Sensitization with ruthenium complexes and infiltration with spiro-OMeTAD hole transporter.
• Variation of polymeric additives (ethyl-cellulose) and sintering treatments (350°C).
• Characterization of film morphology and device performance, including transient perturbation techniques.

Main Results:

• Ethyl-cellulose additive improved dye loading on the ZnO porous electrode.
• Gradual sintering at 350°C effectively removed organic phases from spin-coated ZnO films.
• The best performing device achieved a short-circuit current density of 2.43 mA cm⁻² and a power conversion efficiency of 0.50%.

Conclusions:

• Solution-processed ZnO electrodes can be effectively fabricated for DSSCs.
• Optimized processing parameters, including additive choice and sintering, are critical for performance.
• Further development of ZnO-based DSSCs holds potential for low-cost solar energy conversion.