Efficient NiO/F-TiO₂ nanocomposites for 4-chlorophenol photodegradation

Area of Science:

• Materials Science
• Environmental Chemistry
• Catalysis

Background:

• Photocatalytic degradation is crucial for removing persistent organic pollutants like 4-chlorophenol.
• Titanium dioxide (TiO2) is a widely studied photocatalyst, but its efficiency can be limited by charge carrier recombination.
• Fluorination and doping are strategies to enhance TiO2 photocatalytic activity.

Purpose of the Study:

• To synthesize and characterize NiO/F-TiO2 composites for enhanced photocatalytic degradation of 4-chlorophenol.
• To investigate the effect of NiO content on the photocatalytic performance of F-TiO2.
• To elucidate the structure-activity relationships governing the enhanced photocatalysis.

Main Methods:

• F-TiO2 support synthesized via sol-gel in-situ fluorination.
• NiO/F-TiO2 heterostructures prepared by wet impregnation with varying NiO (0.5-2.0% wt).
• Extensive characterization using XRF, XRD, N2 physisorption, UV-Vis DRS, FTIR, and XPS.

Main Results:

• Fluorination of TiO2 generated ≡Ti-F species, reducing charge carrier recombination and increasing photoactivity.
• NiO/F-TiO2 composites exhibited improved degradation and mineralization of 4-chlorophenol compared to F-TiO2.
• Optimal photocatalytic performance was achieved with 1.0% wt NiO loading, attributed to larger crystallites, lower band gap, and p-n heterojunctions.

Conclusions:

• NiO/F-TiO2 composites are effective for the photocatalytic degradation of 4-chlorophenol.
• Fluorination and NiO doping synergistically enhance TiO2 photocatalytic activity by improving charge separation.
• 1.0% wt NiO loading represents an optimal composition for efficient photocatalytic treatment.