In the present work, henna plant dye was used as a natural photo-sensitizer for n-TiO2-P25 semiconductor. The prepared sensitized nano-photocatalyst was then properly used to selectively oxidize benzyl alcohol to benzaldehyde. The henna natural dye has shown appreciable adsorption onto the surface of n-TiO2-P25 and forms an organic-inorganic composite. The obtained composite improved the photochemical and photocatalytic properties of nano-titanium dioxide semiconductor. The characteristics of the henna sensitized n-TiO2-P25 were investigated through convenient analyses such as Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), X-Ray Diffraction (XRD), and UV-visible/DRS techniques. According to these analyses, the as-prepared composite reduced the band gap energy of titanium dioxide nano-particles and led to the response to visible light. Under the blue LED light irradiation, henna sensitized n-TiO2-P25 oxidized benzyl alcohol to benzaldehyde with excellent selectivity, high yield and short reaction times. Applying henna natural dye as a photo-sensitizer is a more convenient, more cost-effective and greener approach, in comparison with the toxic and costly synthetic dyes.
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Bitaraf,M , Amoozadeh,A and Asghari,M . (2025). Photocatalytic Oxidation of Benzyl Alcohol to Benzaldehyde over Visible Light Sensitized n-TiO2-P25 as Photocatalyst. Applied Chemistry Today, 20(77), 11-22. doi: 10.22075/chem.2025.36342.2328
MLA
Bitaraf,M , , Amoozadeh,A , and Asghari,M . "Photocatalytic Oxidation of Benzyl Alcohol to Benzaldehyde over Visible Light Sensitized n-TiO2-P25 as Photocatalyst", Applied Chemistry Today, 20, 77, 2025, 11-22. doi: 10.22075/chem.2025.36342.2328
HARVARD
Bitaraf M, Amoozadeh A, Asghari M. (2025). 'Photocatalytic Oxidation of Benzyl Alcohol to Benzaldehyde over Visible Light Sensitized n-TiO2-P25 as Photocatalyst', Applied Chemistry Today, 20(77), pp. 11-22. doi: 10.22075/chem.2025.36342.2328
CHICAGO
M Bitaraf, A Amoozadeh and M Asghari, "Photocatalytic Oxidation of Benzyl Alcohol to Benzaldehyde over Visible Light Sensitized n-TiO2-P25 as Photocatalyst," Applied Chemistry Today, 20 77 (2025): 11-22, doi: 10.22075/chem.2025.36342.2328
VANCOUVER
Bitaraf M, Amoozadeh A, Asghari M. Photocatalytic Oxidation of Benzyl Alcohol to Benzaldehyde over Visible Light Sensitized n-TiO2-P25 as Photocatalyst. Applied Chemistry Today. 2025;20(77):11-22 (In Persian). doi: 10.22075/chem.2025.36342.2328
