Metal Oxide Heterojunction for Photocatalytic Activities

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Global demand for improved synthesis techniques for industrial applications.
• Sol-gel-based solution combustion synthesis (SG-SCS) as a method for ordered porous materials.
• Heterojunction formation enhances material properties, particularly photocatalysis.

Purpose of the Study:

• To optimize sol-gel-based solution combustion synthesis (SG-SCS) for producing novel nanomaterials.
• To investigate the formation and properties of heterojunctions using Pearson's hard and soft acids and bases theory.
• To evaluate the photocatalytic efficiency of synthesized nanocomposites (NCs) for dye degradation.

Main Methods:

• Utilized sol-gel-based solution combustion synthesis (SG-SCS).
• Applied Pearson's hard and soft acids and bases theory for host-dopant selection.
• Characterized materials using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), BET analysis, X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray (EDX) spectroscopy.
• Assessed material stability using differential thermogravimetry ratio analysis (DTG) to determine optimal calcination temperature (500 °C).

Main Results:

• Successfully synthesized nanoscale nanoparticles (NPs) and nanocomposites (NCs).
• Validated nanoscale dimensions and confirmed material composition and porosity.
• Established 500 °C as the ideal calcination temperature for stability.
• Demonstrated that NCs degraded Acid Orange 8 (AO8) dye more effectively than bare ZnO.

Conclusions:

• Optimized SG-SCS method for producing ordered porous nanomaterials.
• Pearson's theory is effective for designing heterojunctions with enhanced photocatalytic activity.
• Synthesized NCs exhibit superior photocatalytic degradation of AO8 dye, indicating potential for environmental remediation.