Photocatalytic oxidation of ethanol and isopropanol vapors on cadmium sulfide

Synthesis and solar light catalytic properties of titania–cadmium sulfide hybrid nanostructures

“…Nanosized CdS is known to have the adsorption edge in the range from 520 to 570 nm in its dependence on the structure and the particle size [5]. The spectrum of sample D is a combination of TiO 2 and CdS spectra, however the absorption edge of CdS/TiO 2 is blue-shifted in comparison with that of CdS, likely because of the quantum size effect [14]. The spectrum of TiO 2 /CdS is similar to the spectrum of titanium dioxide, however it has an incomplete reflectance in the range between 450 and 700 nm.…”

“…Fig. 5 shows that samples A and B deactivate after 2 h of reaction, whereas sample C maintains a constant rate of oxidation for 6 h. Such high stability has never been seen in the photocatalytic oxidation of alcohols to aldehydes [5,14,32,33]. Usually, photocatalysts based on CdS and TiO 2 are deactivated after 1-2 h of photooxidation under visible light [5,14,32,33,34].…”

“…High chemical stability and appropriate positions of the flat band potentials required for conducting the desired redox reactions on its surface [13] are the main advantages of TiO 2 . The main disadvantages of TiO 2 are low selectivity toward partial oxidation under aerobic conditions [14] and low absorption of solar light. Both drawbacks can be solved by the use of the well-known photocatalytically active semiconductor, cadmium sulfide (CdS), which has a band gap of about 2.4 eV and correspondingly can be excited with solar radiation [15].…”

Photocatalytic degradation of gaseous benzene with CdS-sensitized TiO2 film coated on fiberglass cloth

“…The direct reaction between photogenerated holes and adsorbed organics (e.g., benzene) can be considered as another way of oxidation on CdS (Eq. (8)) [20,37]. According to these proposed routes, the final products of benzene oxidation, CO 2 …”

“…And the mechanism in gas phase photocatalysis is different from that in the liquid phase reactions. For example, the processes of adsorption of oxygen and mass transport are more easily carried out in the gas phase photocatalytic process [20]. Therefore, it is significant to study the photocatalytic performances toward the pollutants in the gas phase.…”