CdS-sensitized TiO2 nanocorals: hydrothermal synthesis, characterization, application

Area of Science:

• Materials Science
• Nanotechnology
• Photovoltaics

Background:

• Titanium dioxide (TiO2) nanostructures are widely explored for energy applications.
• Enhancing light absorption and charge separation in TiO2-based materials is crucial for improving photovoltaic performance.

Purpose of the Study:

• To synthesize cadmium sulfide (CdS) nanoparticle-sensitized titanium oxide nanocorals (TNC).
• To investigate the structural, optical, and photoelectrochemical properties of the synthesized TiO2-CdS materials.
• To evaluate the performance of TiO2-CdS electrodes in photovoltaic cells.

Main Methods:

• Hydrothermal synthesis of TiO2 nanocorals on FTO substrates.
• Successive ionic layer adsorption and reaction (SILAR) method for loading CdS nanoparticles onto TNC.
• Characterization using optical absorption, XRD, FT-Raman, FT-IR, SEM, and contact angle measurements.
• Photoelectrochemical (PEC) performance testing in various electrolytes.

Main Results:

• CdS sensitization enhanced optical absorption and red-shifted the band edge of TNCs.
• The TiO2-CdS composite exhibited improved PEC performance with a maximum short-circuit current density (Jsc) of 1.04 mA cm⁻².
• Photocurrent in photovoltaic cells increased by 2.7x (vs. CdS) and 32.5x (vs. TiO2).
• Power conversion efficiency reached 0.72%, a 16x and 29x enhancement over bare TiO2 and CdS.

Conclusions:

• The synthesized TiO2-CdS nanostructured material demonstrates superior optical and photoelectrochemical properties.
• CdS nanoparticle sensitization is an effective strategy to enhance the performance of TiO2 nanocorals for photovoltaic devices.
• The improved efficiency highlights the potential of these materials for next-generation solar cells.