Innovative synthesis of YF3‐TiO2 acid‐base catalysts with high surface area by embedding yttrium trifluoride nanoparticles in TiO2 metallogel

• Published in: ChemCatChem 2024-11
• Main Authors: Mishra, Shashank, Ben Salem, Roua, Eternot, Marion, Purohit, Bhagyesh, Bargiela, Pascal, Essayem, Nadine
• Format: Article
• Language: English
• Subjects: Chemical Sciences
• ISSN: 1867-3880; 1867-3899
• DOI: 10.1002/cctc.202401530

Combining a water‐tolerant oxide such as TiO2 with yttrium fluoride is expected to provide catalysts with enhanced acid‐base properties for catalytic applications in water. We present here a new strategy of incorporating pre‐formed YF3 nanoparticles (NPs) in a TiO2‐based metallogel, followed by its soft drying at room temperature to produce YF3‐TiO2 xerogel with high surface area. The as‐synthesized YF3‐TiO2 materials were calcinated at 300 and 400 and characterized by X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), 19F NMR and N2 physisorption, calorimetry of NH3 adsorption, and FT‐IR of pyridine adsorption. These studies indicate that the fluorine is present under a stable form of YF3 for the catalysts calcined at 300 °C. The acid‐base properties of these YF3‐TiO2 catalysts were investigated in a model reaction, i.e., dihydroxyacetone (DHA) conversion in water, and compared with the blank TiO2 and YF3 NPs alone. The incorporation of YF3 in the TiO2 matrix leads to enhanced initial rate of DHA dehydration into pyruvaldehyde, which is slowly converted to lactic acid as the reaction progresses. This suggests that the Brønsted acidity was boosted by the presence of YF3 species via water adsorption in a dissociative form.