Limits...
Feasibility of silver doped TiO2/glass fiber photocatalyst under visible irradiation as an indoor air germicide.

Pham TD, Lee BK - Int J Environ Res Public Health (2014)

Bottom Line: This study investigated the feasibility of using Ag-TiO2 photocatalyst supported on glass fiber (Ag-TiO2/GF) prepared by a sol-gel method as an indoor air germicide.This study confirmed that Ag in Ag-TiO2/GF could work as an electron sink or donor to increase photocatalytic activity and promote the charge separation of electron-hole pairs generated from TiO2 after photon absorption.Ag also acts as an intermediate agent for the transfer of photo-generated electrons from the valence band of TiO2 to an acceptor (O2 gas) to promote photo-oxidation processes.

View Article: PubMed Central - PubMed

Affiliation: Department of Civil and Environmental Engineering, University of Ulsan, Daehakro 93, Namgu, Ulsan 680-749, Korea. thanhdongpham080808@gmail.com.

ABSTRACT
This study investigated the feasibility of using Ag-TiO2 photocatalyst supported on glass fiber (Ag-TiO2/GF) prepared by a sol-gel method as an indoor air germicide. An experimental model was designed to investigate the bacterial disinfection efficiency of Staphylococcus (Staph), the most popular bacterium in hospitals in Korea, by the Ag-TiO2/GF photocatalyst. The silver content in Ag/TiO2 was altered from 1 to 10% to investigate the optimal ratio of Ag doped on TiO2/glass fiber (TiO2/GF) for photocatalytic disinfection of Staph. This study confirmed that Ag in Ag-TiO2/GF could work as an electron sink or donor to increase photocatalytic activity and promote the charge separation of electron-hole pairs generated from TiO2 after photon absorption. Ag also acts as an intermediate agent for the transfer of photo-generated electrons from the valence band of TiO2 to an acceptor (O2 gas) to promote photo-oxidation processes. The photocatalytic disinfection activity of Ag-TiO2/GF under visible light increased with the increase in silver content up to 7.5% and then slightly decreased with further increasing silver content. The highest disinfection efficiency and disinfection capacity of Staph using 7.5% Ag-TiO2/GF were 75.23% and 20 (CFU∙s-1∙cm-2) respectively. The medium level of humidity of 60% ± 5% showed better photocatalytic disinfection than the lower (40% ± 5%) or higher (80% ± 5%) levels.

Show MeSH

Related in: MedlinePlus

SEM photographs of 0 (A), 1 (B), 2.5 (C), 5 (D), 7.5 (E) and 10% (F) Ag-TiO2/GF.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3987034&req=5

ijerph-11-03271-f002: SEM photographs of 0 (A), 1 (B), 2.5 (C), 5 (D), 7.5 (E) and 10% (F) Ag-TiO2/GF.

Mentions: Figure 2 shows the SEM images of 0, 1, 2.5, 5, 7.5 and 10% Ag-TiO2/GF photocatalysts. Glass fiber was used as the substrate for TiO2 deposition. TiO2 in the TiO2/GF was flat-deposited on the surface of the glass fiber (Figure 2A).


Feasibility of silver doped TiO2/glass fiber photocatalyst under visible irradiation as an indoor air germicide.

Pham TD, Lee BK - Int J Environ Res Public Health (2014)

SEM photographs of 0 (A), 1 (B), 2.5 (C), 5 (D), 7.5 (E) and 10% (F) Ag-TiO2/GF.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3987034&req=5

ijerph-11-03271-f002: SEM photographs of 0 (A), 1 (B), 2.5 (C), 5 (D), 7.5 (E) and 10% (F) Ag-TiO2/GF.
Mentions: Figure 2 shows the SEM images of 0, 1, 2.5, 5, 7.5 and 10% Ag-TiO2/GF photocatalysts. Glass fiber was used as the substrate for TiO2 deposition. TiO2 in the TiO2/GF was flat-deposited on the surface of the glass fiber (Figure 2A).

Bottom Line: This study investigated the feasibility of using Ag-TiO2 photocatalyst supported on glass fiber (Ag-TiO2/GF) prepared by a sol-gel method as an indoor air germicide.This study confirmed that Ag in Ag-TiO2/GF could work as an electron sink or donor to increase photocatalytic activity and promote the charge separation of electron-hole pairs generated from TiO2 after photon absorption.Ag also acts as an intermediate agent for the transfer of photo-generated electrons from the valence band of TiO2 to an acceptor (O2 gas) to promote photo-oxidation processes.

View Article: PubMed Central - PubMed

Affiliation: Department of Civil and Environmental Engineering, University of Ulsan, Daehakro 93, Namgu, Ulsan 680-749, Korea. thanhdongpham080808@gmail.com.

ABSTRACT
This study investigated the feasibility of using Ag-TiO2 photocatalyst supported on glass fiber (Ag-TiO2/GF) prepared by a sol-gel method as an indoor air germicide. An experimental model was designed to investigate the bacterial disinfection efficiency of Staphylococcus (Staph), the most popular bacterium in hospitals in Korea, by the Ag-TiO2/GF photocatalyst. The silver content in Ag/TiO2 was altered from 1 to 10% to investigate the optimal ratio of Ag doped on TiO2/glass fiber (TiO2/GF) for photocatalytic disinfection of Staph. This study confirmed that Ag in Ag-TiO2/GF could work as an electron sink or donor to increase photocatalytic activity and promote the charge separation of electron-hole pairs generated from TiO2 after photon absorption. Ag also acts as an intermediate agent for the transfer of photo-generated electrons from the valence band of TiO2 to an acceptor (O2 gas) to promote photo-oxidation processes. The photocatalytic disinfection activity of Ag-TiO2/GF under visible light increased with the increase in silver content up to 7.5% and then slightly decreased with further increasing silver content. The highest disinfection efficiency and disinfection capacity of Staph using 7.5% Ag-TiO2/GF were 75.23% and 20 (CFU∙s-1∙cm-2) respectively. The medium level of humidity of 60% ± 5% showed better photocatalytic disinfection than the lower (40% ± 5%) or higher (80% ± 5%) levels.

Show MeSH
Related in: MedlinePlus