International Journal of Environmental Science and Technology, Jan 28, 2022
The generation of wastewater and its treatment are classified among the biggest challenges for th... more The generation of wastewater and its treatment are classified among the biggest challenges for the health and environmental aspect. Pollution of water through petroleum production and processing is a major concern, and its treatment processes are significantly important. This review primarily focusses on the treatment of oily wastewater through advanced oxidation processes, mainly centered on photocatalytic process. Advanced oxidation processes such as H2O2/UV process, Fenton and photo-Fenton process, ozone process, electrochemical oxidation process, wet air oxidation and supercritical water oxidation process, and photocatalytic process have been discussed. The basic functioning mechanism of photocatalysts and their modifications to improve performance have been explained. This review paper primarily focusses to understand the photocatalysis process, its performance and impact on the degradation of harmful and toxic oily pollutant in water through the creation of reactive oxidation species, for example, hydroxyl radical with the help of solar energy and the complete breakdown of pollutants into the simpler forms like H2O and CO2. The review also provides insight on the future perspective for the researchers working in the field of photocatalysis and oily wastewater treatment.
The exponentially growing energy requirements and, in turn, extensive depletion of non-restorable... more The exponentially growing energy requirements and, in turn, extensive depletion of non-restorable sources of energy are a major cause of concern. Restorable energy sources such as solar cells can be used as an alternative. However, their low efficiency is a barrier to their practical use. This provokes the research community to design efficient solar cells. Based on the study of efficacy, design feasibility, and cost of fabrication, DSSC shows supremacy over other photovoltaic solar cells. However, fabricating DSSC in a laboratory and then assessing their characteristics is a costly affair. The researchers applied techniques of computational chemistry such as Time-Dependent Density Functional Theory, and an ab initio method for defining the structure and electronic properties of dyes without synthesizing them. However, the inability of descriptors to provide an intuitive physical depiction of the effect of all parameters is a limitation of the proposed approaches. The proven potenti...
Abstract Dye sensitized solar cells (DSSC) have drawn attention by way of a photovoltaic device. ... more Abstract Dye sensitized solar cells (DSSC) have drawn attention by way of a photovoltaic device. This technology has advantages such as low cost, easy manufacture process and perform effectively in dusky weather conditions. DSSC comprises of four constituents containing working electrode, light-sensitizer, electrolyte, and counter electrode. Counter electrode is a vital constituent at which reduction of electrolyte redox couple occurs. Generally, platinum (Pt)-coated counter electrodes are preferred in DSSC. The price and unavailability of Pt at large scale restricts its application in DSSC and prompted to design and develop new counter electrode materials. This brief review mainly focuses on carbon nanomaterial counter electrodes such as carbon nanotubes, nanofibers and graphene carbon electrodes as an alternate of Pt-coated counter electrodes and their performances with N719 dye.
Abstract The magnetic graphene oxide (GO) nanocomposites possess unique physicochemical propertie... more Abstract The magnetic graphene oxide (GO) nanocomposites possess unique physicochemical properties, high surface area, high chemical stability, and the ease with which they can be modified and functionalized. In the present work, a nanocomposite of copper ferrite and GO was synthesized through a facile hydrothermal method and their photocatalytic efficiency with dye removal was studied. X-ray diffraction (XRD) was used to characterize the synthesized nanocomposite. The UV–Vis spectrophotometer was used to compare the photocatalytic efficiency for degradation of malachite green dye by using GO/CuFe2O4 nanocomposite, GO and copper ferrite. GO/CuFe2O4 nanocomposite could be recycled and possessed of magnetic and photocatalytic properties hence it can be developed as an inexpensive and alternative photocatalyst for dye removal from wastewater.
Abstract Dye sensitized solar cell (DSSC) is one of the most capable solar cell devices to transf... more Abstract Dye sensitized solar cell (DSSC) is one of the most capable solar cell devices to transform sunlight directly into electricity. DSSC can revolutionize the solar energy industry due to its unique features and has attracted a lot of attention towards this alternative solar cell technology. DSSC can be manufactured with low-cost materials, easy manufacturing methods, less toxic materials, and most important, allocating feasibility of solar cell fabrication at a low cost as compared to traditional solar cells. The NREL certified power conversion efficiency (PCE) for DSSC is 12.3%, whereas the lab-scale PCE has reached 14.3%. In this paper, we present an introduction and classification of PV technologies and a brief description of DSSC development particularly ruthenium complexes based DSSC. This review also presents the structure, operational principle of DSSC and includes the essential criteria for the components of DSSC to offer a vision for the design of highly efficient DSSC. The research progress made in sensitizers especially in ruthenium complexes based have been summarized with their efficiency, dye structure, short circuit current (Isc), open circuit voltage (Voc) and fill factor (FF).
A chromophore containing a coplanar dihexyl-substituted dithienosilole (CL1) synthesised for use ... more A chromophore containing a coplanar dihexyl-substituted dithienosilole (CL1) synthesised for use in dye-sensitised solar cells displayed an energy conversion efficiency of 6.90% under AM 1.5 sunlight irradiation. The new sensitiser showed a similar fill factor and open-circuit voltage when compared with N719. Impedance measurements showed that, in the dark, the charge-transfer resistance of a cell using CL1 in the intermediate-frequency region was higher compared to N719 (69.8 versus 41.3 Ω). Under illumination at AM 1.5G-simulated conditions, the charge-transfer resistances were comparable, indicative of similar recombination rates by the oxidised form of the redox couple. The dye showed instability in ethanol solution, but excellent stability when attached to TiO2. Classical molecular dynamics indicated that interactions between ethanol and the dye are likely to reduce the stability of CL1 in solution form. Time-dependent density functional theory studies were performed to ascerta...
Synthesis of metal nanoparticle–graphene composites without the use of any stabilising ligands ha... more Synthesis of metal nanoparticle–graphene composites without the use of any stabilising ligands has enabled the nanoparticle surface to be available for electron transfer reactions in the development of new counter electrodes for solar cells.
AbstractNitroaromatic compounds are suspected hormone disrupter and considered as toxic priority ... more AbstractNitroaromatic compounds are suspected hormone disrupter and considered as toxic priority pollutants. In the present study, different amounts of titanium dioxide impregnated zeolite Y (Si/Al ratio 5.5) was modified by silver metal ion exchange and its photocatalytic activity was studied for the mineralization of p-nitrotoluene (PNT) in aqueous medium. The synthesized catalysts were characterized by XRD, SEM, inductively coupled plasma, diffuse reflectance spectroscopy, and N2 adsorption techniques. The analysis of degradation intermediates and mineralization pathways were established using high performance liquid chromatography and mass spectroscopy. The mineralization of PNT into final products: CO2, H2O, , and was assessed by chemical oxygen demand (COD) analysis. Langmuir–Hinshelwood kinetic model was proposed for the degradation and the reaction rate constant values were determined from the experimental data using the model. TiO2 loading was optimized from the percentage degradation, rate const...
For the first time, perovskite BaTiO3 nanoparticles were applied as photoelectrode materials for ... more For the first time, perovskite BaTiO3 nanoparticles were applied as photoelectrode materials for quantum dot sensitization in solar cells, yielding a promising power conversion efficiency of 1.51%.
International Journal of Environmental Science and Technology, Jan 28, 2022
The generation of wastewater and its treatment are classified among the biggest challenges for th... more The generation of wastewater and its treatment are classified among the biggest challenges for the health and environmental aspect. Pollution of water through petroleum production and processing is a major concern, and its treatment processes are significantly important. This review primarily focusses on the treatment of oily wastewater through advanced oxidation processes, mainly centered on photocatalytic process. Advanced oxidation processes such as H2O2/UV process, Fenton and photo-Fenton process, ozone process, electrochemical oxidation process, wet air oxidation and supercritical water oxidation process, and photocatalytic process have been discussed. The basic functioning mechanism of photocatalysts and their modifications to improve performance have been explained. This review paper primarily focusses to understand the photocatalysis process, its performance and impact on the degradation of harmful and toxic oily pollutant in water through the creation of reactive oxidation species, for example, hydroxyl radical with the help of solar energy and the complete breakdown of pollutants into the simpler forms like H2O and CO2. The review also provides insight on the future perspective for the researchers working in the field of photocatalysis and oily wastewater treatment.
The exponentially growing energy requirements and, in turn, extensive depletion of non-restorable... more The exponentially growing energy requirements and, in turn, extensive depletion of non-restorable sources of energy are a major cause of concern. Restorable energy sources such as solar cells can be used as an alternative. However, their low efficiency is a barrier to their practical use. This provokes the research community to design efficient solar cells. Based on the study of efficacy, design feasibility, and cost of fabrication, DSSC shows supremacy over other photovoltaic solar cells. However, fabricating DSSC in a laboratory and then assessing their characteristics is a costly affair. The researchers applied techniques of computational chemistry such as Time-Dependent Density Functional Theory, and an ab initio method for defining the structure and electronic properties of dyes without synthesizing them. However, the inability of descriptors to provide an intuitive physical depiction of the effect of all parameters is a limitation of the proposed approaches. The proven potenti...
Abstract Dye sensitized solar cells (DSSC) have drawn attention by way of a photovoltaic device. ... more Abstract Dye sensitized solar cells (DSSC) have drawn attention by way of a photovoltaic device. This technology has advantages such as low cost, easy manufacture process and perform effectively in dusky weather conditions. DSSC comprises of four constituents containing working electrode, light-sensitizer, electrolyte, and counter electrode. Counter electrode is a vital constituent at which reduction of electrolyte redox couple occurs. Generally, platinum (Pt)-coated counter electrodes are preferred in DSSC. The price and unavailability of Pt at large scale restricts its application in DSSC and prompted to design and develop new counter electrode materials. This brief review mainly focuses on carbon nanomaterial counter electrodes such as carbon nanotubes, nanofibers and graphene carbon electrodes as an alternate of Pt-coated counter electrodes and their performances with N719 dye.
Abstract The magnetic graphene oxide (GO) nanocomposites possess unique physicochemical propertie... more Abstract The magnetic graphene oxide (GO) nanocomposites possess unique physicochemical properties, high surface area, high chemical stability, and the ease with which they can be modified and functionalized. In the present work, a nanocomposite of copper ferrite and GO was synthesized through a facile hydrothermal method and their photocatalytic efficiency with dye removal was studied. X-ray diffraction (XRD) was used to characterize the synthesized nanocomposite. The UV–Vis spectrophotometer was used to compare the photocatalytic efficiency for degradation of malachite green dye by using GO/CuFe2O4 nanocomposite, GO and copper ferrite. GO/CuFe2O4 nanocomposite could be recycled and possessed of magnetic and photocatalytic properties hence it can be developed as an inexpensive and alternative photocatalyst for dye removal from wastewater.
Abstract Dye sensitized solar cell (DSSC) is one of the most capable solar cell devices to transf... more Abstract Dye sensitized solar cell (DSSC) is one of the most capable solar cell devices to transform sunlight directly into electricity. DSSC can revolutionize the solar energy industry due to its unique features and has attracted a lot of attention towards this alternative solar cell technology. DSSC can be manufactured with low-cost materials, easy manufacturing methods, less toxic materials, and most important, allocating feasibility of solar cell fabrication at a low cost as compared to traditional solar cells. The NREL certified power conversion efficiency (PCE) for DSSC is 12.3%, whereas the lab-scale PCE has reached 14.3%. In this paper, we present an introduction and classification of PV technologies and a brief description of DSSC development particularly ruthenium complexes based DSSC. This review also presents the structure, operational principle of DSSC and includes the essential criteria for the components of DSSC to offer a vision for the design of highly efficient DSSC. The research progress made in sensitizers especially in ruthenium complexes based have been summarized with their efficiency, dye structure, short circuit current (Isc), open circuit voltage (Voc) and fill factor (FF).
A chromophore containing a coplanar dihexyl-substituted dithienosilole (CL1) synthesised for use ... more A chromophore containing a coplanar dihexyl-substituted dithienosilole (CL1) synthesised for use in dye-sensitised solar cells displayed an energy conversion efficiency of 6.90% under AM 1.5 sunlight irradiation. The new sensitiser showed a similar fill factor and open-circuit voltage when compared with N719. Impedance measurements showed that, in the dark, the charge-transfer resistance of a cell using CL1 in the intermediate-frequency region was higher compared to N719 (69.8 versus 41.3 Ω). Under illumination at AM 1.5G-simulated conditions, the charge-transfer resistances were comparable, indicative of similar recombination rates by the oxidised form of the redox couple. The dye showed instability in ethanol solution, but excellent stability when attached to TiO2. Classical molecular dynamics indicated that interactions between ethanol and the dye are likely to reduce the stability of CL1 in solution form. Time-dependent density functional theory studies were performed to ascerta...
Synthesis of metal nanoparticle–graphene composites without the use of any stabilising ligands ha... more Synthesis of metal nanoparticle–graphene composites without the use of any stabilising ligands has enabled the nanoparticle surface to be available for electron transfer reactions in the development of new counter electrodes for solar cells.
AbstractNitroaromatic compounds are suspected hormone disrupter and considered as toxic priority ... more AbstractNitroaromatic compounds are suspected hormone disrupter and considered as toxic priority pollutants. In the present study, different amounts of titanium dioxide impregnated zeolite Y (Si/Al ratio 5.5) was modified by silver metal ion exchange and its photocatalytic activity was studied for the mineralization of p-nitrotoluene (PNT) in aqueous medium. The synthesized catalysts were characterized by XRD, SEM, inductively coupled plasma, diffuse reflectance spectroscopy, and N2 adsorption techniques. The analysis of degradation intermediates and mineralization pathways were established using high performance liquid chromatography and mass spectroscopy. The mineralization of PNT into final products: CO2, H2O, , and was assessed by chemical oxygen demand (COD) analysis. Langmuir–Hinshelwood kinetic model was proposed for the degradation and the reaction rate constant values were determined from the experimental data using the model. TiO2 loading was optimized from the percentage degradation, rate const...
For the first time, perovskite BaTiO3 nanoparticles were applied as photoelectrode materials for ... more For the first time, perovskite BaTiO3 nanoparticles were applied as photoelectrode materials for quantum dot sensitization in solar cells, yielding a promising power conversion efficiency of 1.51%.
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