Antibacterial activity of TiO2-CaSiTiO5 materials synthesised from a spent catalyst

作者：Cruz Ortiz B R^*; Cortes Hernandez D A; Diaz Jimenez M L; Mauricio Benavides J E

来源：Ceramics International, 2015, 41(2): 2484-2491.

DOI：10.1016/j.ceramint.2014.10.068

• Powders: solid-state reaction
• Composites
• TiO2
• Antibacterial activity

In this work, the antibacterial activity of TiO2-CaSiTiO5 materials against E. coli and S. aureus in presence and absence of UV-light was evaluated. The materials were synthesised by solid-state reaction employing TiO2 from a spent catalyst and wollastonite as raw materials. Physicochemical characterisation of the spent catalyst was performed by atomic absorption spectroscopy, X-ray powder diffraction and scanning electron microscopy. The synthesised materials were characterised by X-ray powder diffraction, scanning electron microscopy, energy dispersive spectroscopy and UV-vis spectroscopy. The following step involved the evaluation of antibacterial activity of selected materials against of E. coli and S aureus. The reaction between TiO2 and CaSiO3 led to the formation of CaSiTiO5 along with TiO2 and CaSiO3. The amount of CaSiTiO5 increased as the TiO2 content was increased. The composite with the highest CaSiTiO5 content (68.6 wt%) demonstrated to have a band gap value lower (2.8 eV) than that of anatase (3.2 eV). Additionally, a wider range of absorption not only in the UV but also in the visible light spectrum was observed for this particular composite. The totality of the pathogenic bacteria used was killed after only 60 min of contact with this composite (CaSiTiO5-TiO2, 68.6-29.4 wt%) under UV-light; the material also exhibited antibacterial activity in dark conditions.

• 出版日期2015-3