Evaluation of bactericidal effect of Nd doped Degussa P-25 on Pseudomonas aeruginosa in sunlight

Titania based photocatalysts have been recently investigated for its capacity to disinfect microorganisms in water. Commercially available TiO₂ was doped with inner transition element neodymium by solid state technique to extend the photocatalytic activity to visible light. . The catalysts were characterized by X-ray diffraction, Transmission electron microscopy, BET and spectral methods. XRD patterns depicted the powders to have higher percentage of anatase phase of Titania with very negligible change in particle size. The presence of dopants could not be identified by XRD, but was confirmed by EDAX analysis. TEM depicted spherical shape with increase in grain size. The surface area measured by BET studies showed a decrease in surface area from 11.091 m² /g to 10.193 m²/g on doping. The absorption spectra indicates neodymium to create interband gap states close to the conduction band or valence band edges due to 4f and 5d levels. This catalyst was tested for its photocatalytic activity in sunlight against an opportunistic Gram negative bacteria Pseudomonas aeruginosa. The increase in photocatalytic activity as a result of incorporation of dopant where in dopants act as electron traps favoring effective charge separation to cause enhanced photo degradation in sunlight.