Facet Dependent Pt Adsorption on Rutile TiO₂ Surface for Efficient Photocatalytic VOCs Removal

Area of Science:

• Materials Science
• Environmental Chemistry
• Catalysis

Background:

• Photocatalytic reactions using titanium dioxide (TiO₂) are effective for removing volatile organic compounds (VOCs).
• Platinum (Pt) deposition on TiO₂ enhances photocatalytic activity, but optimal Pt interaction and dispersion are not fully understood.
• Facet-dependent properties of TiO₂ can influence catalytic performance and cost-efficiency.

Purpose of the Study:

• To investigate the adsorption behavior of platinum species on different rutile TiO₂ facets, specifically (101) and (110).
• To understand how Pt adsorption influences dispersibility and photocatalytic activity for toluene degradation.
• To identify key factors for optimizing Pt deposition on TiO₂ for improved photocatalysis.

Main Methods:

• Computational investigation of Pt adsorption on rutile TiO₂ (101) and (110) surfaces.
• Analysis of Pt ion species (e.g., Pt(OH)₂, PtCl₅⁻) and their adsorption affinities.
• Evaluation of photocatalytic activity for toluene degradation using Pt-deposited TiO₂ with controlled facet orientation.

Main Results:

• The rutile TiO₂ (101) facet shows significantly higher adsorption affinity for Pt ions like Pt(OH)₂ compared to the (110) facet, attributed to higher surface energy.
• Enhanced adsorption of Pt(OH)₂ on the (101) facet leads to increased Pt dispersibility and improved photocatalytic performance in toluene degradation.
• Pt species adsorption is strongly dependent on both the TiO₂ surface facet and the specific Pt ion involved.

Conclusions:

• Controlling the facet orientation of TiO₂ is crucial for optimizing platinum deposition and enhancing photocatalytic efficiency.
• Understanding and selecting appropriate Pt ion species for adsorption can significantly improve catalyst performance.
• These findings provide a basis for designing more efficient TiO₂-based photocatalysts for air purification.