Underestimated Properties of Nanosized Amorphous Titanium Dioxide

Area of Science:

• Materials Science
• Nanotechnology
• Photochemistry

Background:

• Titanium dioxide (TiO2) is widely used in various applications due to its photosensitive properties.
• Research has primarily focused on crystalline TiO2 nanoparticles for their high photoactivity.
• Amorphous TiO2 has been largely overlooked due to assumed photocatalytic inactivity.

Purpose of the Study:

• To provide experimental evidence for the UV-protective properties of nano-sized amorphous TiO2.
• To investigate the safety and potential cosmetic applications of amorphous TiO2.
• To correlate the properties of amorphous TiO2 with its surface chemistry.

Main Methods:

• Experimental characterization of nano-sized amorphous TiO2.
• Assessment of UV-protective properties and cytotoxicity on fibroblast cells.
• In situ Fourier Transform Infrared (FTIR) spectroscopy to study surface species.

Main Results:

• Amorphous n-TiO2 exhibits photocatalytic inactivity and low cytotoxicity.
• Cells treated with amorphous TiO2 show enhanced survival under UV radiation.
• In situ FTIR studies indicate a low ability to form hydroperoxo surface species on amorphous TiO2.

Conclusions:

• Nano-sized amorphous TiO2 possesses significant UV-protective properties.
• Its photocatalytic inactivity and low cytotoxicity make it a safe candidate for cosmetic applications.
• The reduced formation of hydroperoxo surface species contributes to the low toxicity of amorphous TiO2.