Application of Nanoscale Silver-Doped Titanium Dioxide as Photocatalyst for Indoor Airborne Bacteria Control: A Feasibility Study in Medical Nursing Institutions

Abstract

The deterioration of indoor air quality because of airborne bacterial consortia is a widespread environmental problem. The main objective of this study is to evaluate the feasibility of applying nanoscale silver-doped titanium dioxide (TiO2) photocatalysis (nano-Ag/TiO2) particles as a photocatalyst to enhance the disinfecting capability of bacterial restraining equipment in a medical nursing institution. A full-scale, on-site study was initiated to test the effectiveness of adding the photocatalyst to various air quality control equipments; that is, fixed full-covering type (FF type), underneath swinging type (US type), and lateral swinging type (LS type). Results from this study indicate that the FF type has the best bacterial restraining rate (81%) as compared with the LS type (66%) and the US type (61%). Similar results are obtained at different heights (90 and 180 cm) of the nursing institutions, revealing that freshly disinfected air is provided regardless of location as long as the air quality control equipment is in operation. The proposed equipment can disinfect air to effectively restrain bacteria as demonstrated on-site in medical nursing institutions; the results will also be for designing integrated, commercialized, large-scale applications in the future.

Synthesis of Silver‐Doped Titanium TiO2 Powder‐Coated Surfaces and Its Ability to Inactivate Pseudomonas aeruginosa and Bacillus subtilis

“…Several proposed mechanisms for cell killing by the TiO 2 photocatalytic processes were reported [17,18,20,36]. One research group reported direct evidence of cell membrane damage by the irradiation of a thin transparent TiO 2 film to Journal of Nanomaterials time, while P. aeruginosa and B. subtilis proliferated well in the glass plate as well as venetian blinds which were not coated with Ag-TiO 2 nanoparticles.…”

“…The photocatalytic property has been widely studied in a variety of microorganisms such as viruses, bacteria, fungi, and algae. The main advantages of photocatalytic method are operation under ambient temperature and pressure, high stability and the low cost of catalyst, completed mineralization without creating secondary pollution, and possibility of using solar light ( [12,[16][17][18][19][20][21][22] dheaya et al, 2008, [23]).…”

“…TiO 2 is used in form of powder, films, and nanocomposites with a strong UV light as well as visible light. Little research work has been done regarding coating of metal-doped and nondoped TiO 2 nanoparticles aqueous solutions on substrates [12,15,17,19,23]. Recently, nanosize (<100 nm) TiO 2 particles have attracted a lot of attention of many researchers [24].…”