Bimetallic Implanted Plasmonic Photoanodes for TiO₂ Sensitized Third Generation Solar Cells

Area of Science:

• Materials Science
• Nanotechnology
• Renewable Energy

Background:

• Third-generation solar cells require improved light harvesting and reduced recombination for higher power conversion efficiency (PCE).
• Titanium dioxide (TiO2) is a key sensitizer, but its efficiency can be limited by optical and charge recombination properties.

Purpose of the Study:

• To enhance the PCE of dye-sensitized solar cells (DSSCs) by simultaneously improving light harvesting and inhibiting recombination.
• To investigate the effects of embedded bimetallic gold (Au) and silver (Ag) metal nanoparticles (Mnps) in TiO2 using ion implantation.

Main Methods:

• Ion implantation of Au and Ag nanoparticles into TiO2 at a low fluence range (6 × 10^15 ions cm^-2).
• Fabrication and testing of DSSCs incorporating the modified TiO2 photoanode.
• Characterization of optical and electrical properties, including localized surface plasmon resonance (LSPR) and charge transport.

Main Results:

• The best performing Au-Ag implanted DSSC showed an 87.97% enhancement in PCE compared to the unimplanted device.
• Embedded Au-Ag Mnps improved light harvesting by matching the LSPR absorption of nanoparticles with the absorption bands of the N719 dye.
• Au and Ag nanoparticles acted as charge separation centers, inhibiting recombination at the photoanode/electrolyte interface and prolonging electron lifetime.

Conclusions:

• Simultaneous enhancement of light harvesting and charge recombination inhibition is achievable using bimetallic Au-Ag nanoparticles in TiO2.
• Ion implantation is an effective technique for embedding Mnps in TiO2 for DSSC applications.
• The plasmonic and charge separation effects of Au-Ag Mnps significantly boost the performance of dye-sensitized solar cells.