A review of the mechanisms and modeling of photocatalytic disinfection

Growth of non-phototrophic microorganisms using solar energy through mineral photocatalysis

“…These results are in contrast to those previously reported about photocatalytic disinfection of bacteria by semiconductors, such as TiO 2 -based photocatalysts 28 . In those photocatalysts, photogenerated reactive oxygen species (ROS) were believed to be the 'killers' of bacteria, where the cell wall of bacteria adsorbed onto semiconductors could be quickly damaged by ROS through photocatalytic oxidation reactions 29,30 . Because of the short lifetime of ROS, only those microorganisms with an immediate contact with semiconductors are threatened 31 .…”

“…The cells on the graphite electrode were fixed using 2.5% glutaraldehyde at 4 °C overnight and washed with 0.1 M sodium phosphate buffer (pH 7.2) 3 times (each for 15 min). The cells were dehydrated with a series of ethanol-water mixtures (30,50,70,85,95 and 100 vol% of ethanol) for 15 min each. After critical point drying, the samples were mounted on a silicon plate using double-sided carbon tape and then coated with gold for ESEM observation.…”

ZrNO–Ag co-sputtered surfaces leading to E. coli inactivation under actinic light: Evidence for the oligodynamic effect

“…Recently, we have reported the mechanism of the damage induced by TiO 2 photocatalysis on the bilayer cell-envelope of Escherichia coli in several studies [20][21][22][23]. Other groups working in the disinfection field have also addressed the mechanism of disinfection [24][25][26][27]. The E. coli and MRSA viability as a function of time was monitored by direct transfer on plate and by stereomicroscopy.…”

Unveiling the photoelectrocatalytic inactivation mechanism of Escherichia coli : Convincing evidence from responses of parent and anti-oxidation single gene knockout mutants

“…Traditionally widely-used chlorinated disinfection techniques have been criticized for generating hazardous by-products (Kulkarni and Chellam, 2010). Photocatalytic (PC) technology based on semiconductors has been explored as a promising candidate for water disinfection, because of its solar-driven potential and self-cleaning capacity (Rincon and Pulgarin, 2007;Dalrymple et al, 2010;Foster et al, 2011;Gao et al, 2013;Shi et al, 2015). Semiconductors, like TiO 2, can absorb photon energy and generate hole (h þ ) and electron (e À ) pairs, subsequently reacting with H 2 O and O 2 to form reactive oxygen species (ROSs) such as OH, O 2 À , and H 2 O 2 .…”