Review on the criteria anticipated for the fabrication of highly efficient ZnO-based visible-light-driven photocatalysts

Adsorptive removal and photocatalytic degradation of organic pollutants using metal oxides and their composites: A comprehensive review

Photocatalysis is an ecofriendly technique that emerged as a promising alternative for the degradation of many organic pollutants. The weaknesses of the present photocatalytic system which limit their industrial applications include low-usage of visible light, fast charge recombination, and low migration ability of the photo-generated electrons and holes. Therefore, various elements such as noble metals and transition metals as well as non-metals and metalloids (i.e., graphene, carbon nanotube, and carbon quantum dots) are doped into the photocatalyst as co-catalysts to enhance the photodegradation performance. The incorporation of the co-catalyst which alters the photocatalytic mechanism was discussed in detail. The application of photocatalysts in treating persistent organic pollutants such as pesticide, pharmaceutical compounds, oil and grease and textile in real wastewater was also discussed. Besides, a few photocatalytic reactors in pilot scale had been designed for the effort of commercializing the system. In addition, hybrid photocatalytic system integrating with membrane filtration together with their membrane fabrication methods had also been reviewed. This review outlined various types of heterogeneous photocatalysts, mechanism, synthesis methods of biomass supported photocatalyst, photocatalytic degradation of organic substances in real wastewater, and photocatalytic reactor designs and their operating parameters as well as the latest development of photocatalyst incorporated membrane.

An overview of photocatalytic degradation: photocatalysts, mechanisms, and development of photocatalytic membrane

Water is an essential part of life and its availability is important for all living creatures. On the other side, the world is suffering from a major problem of drinking water. There are several gases, microorganisms and other toxins (chemicals and heavy metals) added into water during rain, flowing water, etc. which is responsible for water pollution. This review article describes various applications of nanomaterial in removing different types of impurities from polluted water. There are various kinds of nanomaterials, which carried huge potential to treat polluted water (containing metal toxin substance, different organic and inorganic impurities) very effectively due to their unique properties like greater surface area, able to work at low concentration, etc. The nanostructured catalytic membranes, nanosorbents and nanophotocatalyst based approaches to remove pollutants from wastewater are eco-friendly and efficient, but they require more energy, more investment in order to purify the wastewater. There are many challenges and issues of wastewater treatment. Some precautions are also required to keep away from ecological and health issues. New modern equipment for wastewater treatment should be flexible, low cost and efficient for the commercialization purpose.

Role of Nanomaterials in the Treatment of Wastewater: A Review

https://minerva-access.unimelb.edu.au/bitstream/handle/11343/127237/RevisedManuscript_Ntoday_final_rev.pdf

Metal-phenolic networks as a versatile platform to engineer nanomaterials and biointerfaces

Comparison of palladium/zinc oxide photocatalysts prepared by different palladium doping methods for congo red degradation.

Fe-tannic acid complex dye as photo sensitizer for different morphological ZnO based DSSCs.

Investigation of Vegetable Tannins and Their Iron Complex Dyes for Dye Sensitized Solar Cell Applications

Immobilized enzymes are significantly studied both environmental and textile industries. In this work, glucose oxidase was immobilized on the tannin coated NiFe2O4 magnetic nanoparticles for decolorization of indigo carmin. The as-synthesized all magnetic nanoparticles were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, UV–vis spectroscopy, Thermogravimetric analysis, Vibrating sample magnetometer and Scanning electron microscopy. The activity of the free and immobilized glucose oxidase in various temperature and pH values was investigated. Finally, the produced immobilized glucose oxidase was applied for decolorization of indigo carmine due to production of H2O2. The decolorization yields of indigo carmine are 98.6% and 37.6% of the glucose oxidase immobilized on tannin modified NiFe2O4 in presence of the both of UV-light and iron(II)chloride for 90 min, respectively. The results exude that the obtained photocatalysts exhibit excellent both photocatalytic efficiency and easy separation from dye solution by an external magnet.

Efficiency of glucose oxidase immobilized on tannin modified NiFe2O4 nanoparticles on decolorization of dye in the Fenton and photo-biocatalytic processes

A novel quercetin and Fe-quercetin complex dyes have been prepared and used in DSSCs. The prepared dyes were characterized via FTIR, Raman, UV–vis and CV techniques. The HOMO and LUMO energy levels and possible mechanism of iron complexation were discussed in detailed. A TiO 2 was synthesized via microwave hydrothermal method. The photoanode TiO 2 thin film was prepared by doctor blade technique. The powder and thin film TiO 2 photoanodes were characterized via XRD, SEM, Raman and DRS techniques. The quercetin and Fe-quercetin have employed as sensitizers in DSSCs and their electrochemical characterization was carried out. The most probable mechanism of the Fe-quercetin complexes was elucidated by means of Raman spectroscopy measurements. The conversion efficiencies of quercetin and Fe-quercetin based solar cells are obtained as 1.27% and 3.84%, respectively. The iron complexation of quercetin increased the cell efficiency by 67%, compared to quercetin-based solar cell. Fe-quercetin as a natural dye metal complexes offered a new alternative approach to the other natural dye-sensitized solar cells, which has low-conversion efficient characteristics in natural dyes-sensitized solar cells. Additionally, the Fe-quercetin sensitizer is an alternative to organic synthetic dyes and has advantages such as easy synthesis, low cost and abundantly finding in everywhere.

Soner Çakar

Papers

Comparison of palladium/zinc oxide photocatalysts prepared by different palladium doping methods for congo red degradation.

Fe-tannic acid complex dye as photo sensitizer for different morphological ZnO based DSSCs.

Investigation of Vegetable Tannins and Their Iron Complex Dyes for Dye Sensitized Solar Cell Applications

Efficiency of glucose oxidase immobilized on tannin modified NiFe2O4 nanoparticles on decolorization of dye in the Fenton and photo-biocatalytic processes

The effect of iron complexes of quercetin on dye-sensitized solar cell efficiency