Mechanism of enhanced photocatalysis with polyhydroxy fullerenes

• Published in: Applied catalysis. B, Environmental Vol. 79; no. 4; pp. 376 - 381
• Main Authors: Krishna, Vijay, Yanes, David, Imaram, Witcha, Angerhofer, Alex, Koopman, Ben, Moudgil, Brij
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 08-03-2008; Elsevier
• Subjects: Anatase; Catalysis; Chemistry; Colloidal state and disperse state; Cross-disciplinary physics: materials science; rheology; Degussa P25; Disinfection; EPR; Escherichia coli; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; Fullerols; General and physical chemistry; Hydroxyl radicals; Materials science; Nanoparticles; Photochemistry; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); Physics; Procion red; Specific materials; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Titanium dioxide; Procion red; Nanoparticles; Anatase; EPR; Escherichia coli; Hydroxyl radicals; Disinfection; Fullerols; Titanium dioxide; Degussa P25; Nanoparticle; Photocatalysis; Transition element compounds; EPR spectrometry; Mechanism; Heterogeneous catalysis; Fullerenes; Titanium oxide; Hydroxyl; Environmental protection
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2007.10.020

Polyhydroxy fullerenes (PHF) have been applied for increasing the photocatalytic degradation rate of TiO2. Scavenging of photo-generated electrons and therefore higher generation of hydroxyl radicals was hypothesized as the mechanism for the observed enhancement. The present study confirms the increase in generation of hydroxyl radicals with electron paramagnetic resonance (EPR) spectroscopy. The concentration of hydroxyl radicals generated by a mixture of TiO2 and PHF was up to 60% greater than the concentration obtained without PHF. These results are consistent with the observed enhancement in dye degradation and microbial inactivation experiments. The current study also demonstrates that PHF can improve the photocatalytic activity of different TiO2.