A novel stellerite-based photocatalytic composite and its enhanced disinfection application

Publication date: Available online 26 March 2018
Source:Journal of Photochemistry and Photobiology B: Biology
Author(s): Wanzhong Zhang, Haiyu Huang, Zhiming Sun, Shuilin Zheng, Caihong Yu
The aim of this work was to prepare, characterize and evaluate the potential of novel ZnO/stellerite composite photocatalysts against Staphylococcus aureus (S. aureus). SEM/EDS studies employed to study the surface morphological properties revealed stellerite as the catalysts carrier played a role of dispersant for ZnO nanoparticles. The XRD patterns of the ZnO/stellerite indicated hexagonal crystal structure with 20–30 nm size. It was found that the crystallite size of ZnO/stellerite was much smaller as compared to pure ZnO and increased with increasing ZnO loading amount. The results of optical properties of ZnO/stellerite showed smaller band gap in contrast to pure ZnO, investigated by UV–vis absorption. Due to the optimum ZnO loading, the as-prepared ZnO-20 composite had the highest BET surface area and the pore volume. Using the TG-DSC measurement, the high thermal stability of the product was studied for different temperature values. Antibacterial activity of ZnO/stellerite affected by the ZnO loading, concentration of samples and light conditions (under dark and UV irradiation conditions) was examined by disinfection of S. aureus. The as-prepared ZnO-20 composite with 100 mg/L was found to exhibit excellent inactivation efficiencies (87.65% in the dark and 97.67% under UV illumination) towards S. aureus. Compared with pure ZnO, the obtained composite photocatalysts showed significantly better antibacterial performance by studying the disinfection kinetics of S. aureus. Thus, the present study reveals that the novel ZnO/stellerite shows great potential for its use in the targeted disinfection applications.

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