hrvatski

Conductyve polymer/TiO2 photocatalytic nanocomposites for wastewater treatment

Methods for wastewater treatment are biological, physical, physical-chemical and chemical. Biological methods include decomposition of contaminants in processes that are governed by certain type of microorganisms, the physical methods include adsorption on the surface or inside of the porous particles, eg. zeolites or clays. Physical-chemical methods, such as coagulation/flocculation, are very efficient and effective but their lack is a large amount of sludge that is lagging behind. The chemical methods are primarily processes of oxidation and reduction of contaminants in the polluted waters. A special group of chemical methods for wastewater treatment processes, which are intensively investigated and commercially applied, are the advanced oxidation processes (AOPs). Their advantage, compared to conventional chemical treatment processes of water, are the possibility of complete decomposition of the organic contaminants to water, carbon dioxide, nitrate, sulphate, chloride ... A large number of semiconductors like metal oxides have excellent photocatalytic activity, and specially good photocatalyst is titanium dioxide, TiO2. It is suitable for the application because of its very good properties, such as chemical and biological inertness, photo activity, ease of production, low cost, non-toxicity and friendliness to the environment. The photocatalytic activity of TiO2 results from the formation of photogenerated holes, h+, and electrons, e- due to the absorption of ultraviolet light, which energy is equal to the energy of its band gap, Ebg. The recent research is devoted to the development of TiO2 catalyst with expanded photocatalytic activity that is shifted to the visible part of the UV/Vis light of solar radiation. Extended activity of TiO2 can be achieved by doping and dopant among the many can be the conductive polymer. Thus, the nanoparticles of TiO2 as the semiconducting photocatalyst in combination with the conductive polymer (CP) exhibit a synergistic effect and photocatalytic activity in the visible part of the Sun light, Figure 1. By the synthesis of conductive polymers of corresponding structure: polyaniline (PANI), polypyrrole (PPY) and poly(3, 4-ethylenedioxythiophene) (PEDOT) with TiO2 nanoparticles the polymeric nanocomposite with increased photocatalytic activity in the VIS light can be prepared. In other words, in this case the initiation of the photocatalytic degradation of pollutants in waste water by solar irradiation will be possible. This would, further enable the development and application of advanced technologies for wastewater/industrial wastewater treatment in environment protection.

vodljivi polimeri ; TiO2 ; fotokatalitička aktivnost ; nanokompoziti

nije evidentirano

engleski

Conductyve polymer/TiO2 photocatalytic nanocomposites for wastewater treatment

Methods for wastewater treatment are biological, physical, physical-chemical and chemical. Biological methods include decomposition of contaminants in processes that are governed by certain type of microorganisms, the physical methods include adsorption on the surface or inside of the porous particles, eg. zeolites or clays. Physical-chemical methods, such as coagulation/flocculation, are very efficient and effective but their lack is a large amount of sludge that is lagging behind. The chemical methods are primarily processes of oxidation and reduction of contaminants in the polluted waters. A special group of chemical methods for wastewater treatment processes, which are intensively investigated and commercially applied, are the advanced oxidation processes (AOPs). Their advantage, compared to conventional chemical treatment processes of water, are the possibility of complete decomposition of the organic contaminants to water, carbon dioxide, nitrate, sulphate, chloride ... A large number of semiconductors like metal oxides have excellent photocatalytic activity, and specially good photocatalyst is titanium dioxide, TiO2. It is suitable for the application because of its very good properties, such as chemical and biological inertness, photo activity, ease of production, low cost, non-toxicity and friendliness to the environment. The photocatalytic activity of TiO2 results from the formation of photogenerated holes, h+, and electrons, e- due to the absorption of ultraviolet light, which energy is equal to the energy of its band gap, Ebg. The recent research is devoted to the development of TiO2 catalyst with expanded photocatalytic activity that is shifted to the visible part of the UV/Vis light of solar radiation. Extended activity of TiO2 can be achieved by doping and dopant among the many can be the conductive polymer. Thus, the nanoparticles of TiO2 as the semiconducting photocatalyst in combination with the conductive polymer (CP) exhibit a synergistic effect and photocatalytic activity in the visible part of the Sun light, Figure 1. By the synthesis of conductive polymers of corresponding structure: polyaniline (PANI), polypyrrole (PPY) and poly(3, 4-ethylenedioxythiophene) (PEDOT) with TiO2 nanoparticles the polymeric nanocomposite with increased photocatalytic activity in the VIS light can be prepared. In other words, in this case the initiation of the photocatalytic degradation of pollutants in waste water by solar irradiation will be possible. This would, further enable the development and application of advanced technologies for wastewater/industrial wastewater treatment in environment protection.

Conductive polymer ; TiO2 ; photocatalytic activity ; nanocomposites

nije evidentirano