The synergistic effect of binary CdTiO2 and ternary NiCdTiO2 on the photocatalytic efficiency of ... more The synergistic effect of binary CdTiO2 and ternary NiCdTiO2 on the photocatalytic efficiency of TiO2 nanoparticles was investigated. The SEM analysis demonstrates spherical TiO2 NPs of different sizes present in agglomerated form. The structural analysis of the nanocomposites reveals a porous structure for TiO2 with well deposited Cd and Ni NPs. TEM images show NiCdTiO2 nanocomposites as highly crystalline particles having spherical and cubical geometry with an average particle size of 20 nm. The EDX and XRD analysis confirm the purity and anatase phase of TiO2, respectively. Physical features of NiCdTiO2 nanocomposite were determined via BET analysis which shows that the surface area, pore size and pore volume are 61.2 m2/g, 10.6 nm and 0.1 cm3/g, respectively. The absorbance wavelengths of the CdTiO2 and NiCdTiO2 nanocomposites have shown red shift as compared to the neat TiO2 due to coupling with Ni and Cd that results in the enhanced photocatalytic activity. The photocatalytic ...
The conventional chemical methods of nanoparticles synthesis have been effectively replaced by na... more The conventional chemical methods of nanoparticles synthesis have been effectively replaced by nanoparticle synthesis mediated by plants. The current study describes the environmental friendly synthesis of chromium oxide nanoparticles (Cr2O3 NPs) using Erythrophleum guineense plant extract. The synthesis of Cr2O3 NPs was validated by UV/VIS spectroscopy, Energy Dispersive X-Ray (EDX), Scanning Electron Microscopy (SEM), and X-ray diffraction (XRD) studies. The appearance of the Sharpe peak at 460 nm in the UV/Vis spectrum and the colour change caused by surface plasma resonance confirmed the formation of Cr2O3 NPs. The EDX spectrum of Cr2O3 nanoparticles revealed the presence of carbon, oxygen, and chromium, while SEM analysis revealed an irregular round morphology (with a size below 400 nm). In addition, XRD studies suggested their crystalline nature by the characteristic peaks at 34° and 36° and 42° (2Ɵ), respectively. The green synthesized Cr2O3 NPs showed promise as in-vitro cho...
The Nickel oxide nanoparticles (NiO NPs) and Nickel oxide/Nanoclay nanocomposite (NiO/Nc NC) were... more The Nickel oxide nanoparticles (NiO NPs) and Nickel oxide/Nanoclay nanocomposite (NiO/Nc NC) were synthesized by chemical reduction method and used for the photodegradation of Orange II dyes in aqueous solution. The synthesized samples were characterized through SEM, EDX, FTIR and TGA. The SEM analysis presented that the NiO NPs are spherical with irregular shapes and sizes. The size of particles is in the range of 100–400 nm. It was also observed that the NiO NPs are deposited on the surface of Nanoclay. The EDX study confirmed the formation of metal NPs and verify and purity. The FT-IR spectra of NiO and NiO/Nc NC presented peaks at 432 cm−1 and 504 cm−1, which correspond to NiO while peak at 1090–940 cm−1 is due to Si–O stretching vibration of orthosilicate anions and Si–O–Al groups. The photodegradation study illustrated that the NiO NPs and NiO/Nc NC degraded about 93 and 96% Orange II in aqueous medium, respectively within 20 min. The effect of various parameters like initial ...
Removal of heavy metals and dyes from wastewater has received great attention due to scarcity of ... more Removal of heavy metals and dyes from wastewater has received great attention due to scarcity of clean water worldwide. Herein an approach was introduced to attain this goal by employing a single material. Chitosan films were prepared, cross-linked it and utilized for the adsorption of cobalt from aqueous medium. The cobalt adsorbed chitosan was then reutilized as a photocatalyst for the photodegradation of methyl violet dyes. The prepared chitosan, cross-linked chitosan and cobalt adsorbed cross-linked chitosan were characterized through scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). SEM and EDX confirmed the adsorption of cobalt on the cross-linked chitosan. TGA analysis proved the increase in thermal stability with cross-linking while FTIR confirmed the cross-linking of chitosan. Maximum cobalt adsorption of 144 mg/g occurs at 600 ppm salt concentration. The photodegradation s...
Green synthesis has been introduced as an alternative to chemical synthesis due to the serious co... more Green synthesis has been introduced as an alternative to chemical synthesis due to the serious consequences. Metal nanoparticles synthesized through green approach have different pharmaceutical, medical and agricultural applications. The present study followed a green and simple route for the preparation of potentially bioactive gold nanoparticles (Au NPs). Au NPs were prepared via green synthesis approach using crude basic alkaloidal portion of the tuber of Delphinium chitralense. The green synthesized Au NPs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) fourier transform infrared (FTIR), and UV-Visible spectrophotometer. Morphological analysis shows that Au NPs have cubic geometry with different sizes. UV-Vis spectroscopic analysis confirmed the synthesis of Au NPs while XRD proved their pure crystalline phase. The Au NPs showed promising dose dependent inhibition of both AChE and BChE as compared to the c...
Journal of Environmental Health Science and Engineering, 2020
Background Photodegradation of organic pollutants is considered to be the most suitable and cheap... more Background Photodegradation of organic pollutants is considered to be the most suitable and cheaper technique to counter the decontamination issues. Metal nanoparticles are considered to be the most effective heterogeneous photocatalysts for photodegradation of organic pollutants. Besides, iron oxide nanoparticles are well-known photocatalysts for degrading organic pollutants. Methods We reported the synthesis of neat iron oxide nanoparticles (Fe 3 O 4 NPs) and zirconia supported iron oxide nanoparticles (Fe 3 O 4 /ZrO 2 NPs) by facile chemical reduction technique for photodegradation ofa toxic azo dye namely methyl red. Results The XRD and FTIR analysis has demonstrated a crystalline phase Fe 3 O 4 NPs. The morphological features via scanning electronic microscopy (FESEM) suggested agglomerated morphology of neat Fe 3 O 4 NPs with 803.54 ± 5.11 nm average particle size and revealed the uniform morphology and homogenous dispersion of Fe 3 O 4 NPs over ZrO 2 surface in Fe 3 O 4 /ZrO 2 nanocomposite. A polydispersity index (PDI) of 0.47 showed sufficient variations in the particle size of neat Fe 3 O 4 NPs, which is also supported by the results obtained from atomic force microscopy (AFM), FESEM and Transmission Electron Microscopy (TEM). Fe 3 O 4 /ZrO 2 NPs demonstrated efficient methyl red degradation over a short period of time under simulated light and degraded about~91.0 ± 1.0% and 87.0 ± 1.0% dye in 40 min, under UV and visible light, respectively. Conclusion The excellent photodegradation efficacy and sustainability of Fe 3 O 4 /ZrO 2 NPs can be attributed to the homogenous distribution of Fe 3 O 4 NPs over ZrO 2 , which facilitates the generation of photoexcitons (electrons and holes), enhanced charge transfer and minimize the charge recombination.
Photodegradation is the chemical conversion of large, toxic, and complex molecules into non-toxic... more Photodegradation is the chemical conversion of large, toxic, and complex molecules into non-toxic, simpler, and lower molecular weight species due to light exposure. Heterogeneous photocatalysis has sufficient potential to degrade toxic organic pollutants present in wastewater. As industries discharge their effluents containing organic pollutants into natural water bodies, which penetrate into the subsurface through connected pores it is necessary to study this process in natural or tap water. Tap water (TW) is mainly obtained from underground wells having inorganic salts in a minute quantity with a conductivity of 500 μS/cm. TW contains inorganic anions, which affect the photocatalytic activity and photocatalysis process. The aim of this review is to evaluate the effect of TW on the photo-degradation of organic pollutants such as dyes, pharmaceutical products, pesticides, etc., with the support of the literature. The TW had a diverse effect on the photodegradation of organic pollut...
The unavailability of clean drinking water is one of the significant health issues in modern time... more The unavailability of clean drinking water is one of the significant health issues in modern times. Industrial dyes are one of the dominant chemicals that make water unfit for drinking. Among these dyes, methylene blue (MB) is toxic, carcinogenic, and non-biodegradable and can cause a severe threat to human health and environmental safety. It is usually released in natural water sources, which becomes a health threat to human beings and living organisms. Hence, there is a need to develop an environmentally friendly, efficient technology for removing MB from wastewater. Photodegradation is an advanced oxidation process widely used for MB removal. It has the advantages of complete mineralization of dye into simple and nontoxic species with the potential to decrease the processing cost. This review provides a tutorial basis for the readers working in the dye degradation research area. We not only covered the basic principles of the process but also provided a wide range of previously p...
A specific finger-projected fixed-bed reactor (FPFBR) was designed to efficiently utilize magneti... more A specific finger-projected fixed-bed reactor (FPFBR) was designed to efficiently utilize magnetic nanoparticles (MnFe2O4/Bi-MnFe2O4) for a model reaction (hydrogenation of a greenhouse gas, CO2, to valuable products: VPs). Coprecipitation method, with desired modification was used for the preparation of magnetic nanoparticles (MNPs) with controlled shape and size. Eighteen fingers in a single chamber were designed in the fixed-bed reactor’s skeleton; each finger worked as an independent reaction core. Controlled flow of hydrogen and CO2 was continuously provided to preheated reaction cores (catalyst beds) from saturator. One of the major products methanol {(%: Conv, 22/Sel 61)} among VPs was identified and quantified by GC. The efficiency of self-designed reactor was 74% for the direct catalytic hydrogenation of CO2 to valuable organic products.
Nylon 6/6 and ZnO/nylon 6/6 nanocomposite films were prepared by solvent casting method. Morpholo... more Nylon 6/6 and ZnO/nylon 6/6 nanocomposite films were prepared by solvent casting method. Morphological study displayed that ZnO NPs are better dispersed in nylon 6/6. However, some agglomerations were found by the incorporation of high quantities of fillers. The thermal stabilities of neat nylon 6/6 films decreased by addition of nanoparticles (NPs). DSC study shows that the NPs slow down the crystallization rate of neat polymer matrix. POM of Nylon 6/6 upon crystallization showed distinct sized spherulites, which decreased by the incorporation of NPs because of nucleation effect of NPs. The mechanical properties of neat polymer are decreased by addition of ZnO NPs, which might be due to agglomeration of fillers. The neat nylon 6/6 and ZnO/nylon 6/6 nanocomposite were used for the photodegradation of alizarin red (AR) dye, which shows that pure nylon 6/6 degraded about 28% dye while 30% ZnO/Nylon 6/6 degraded about 58.3% dye within 5 h irradiation.
Abstract. The green synthesis of gold nanoparticles (Au NPs) from their precursor was carried out... more Abstract. The green synthesis of gold nanoparticles (Au NPs) from their precursor was carried out using Delphinium uncinatum and Erythrophyleum guineense plants extracts. The Au NPs obtained were characterized by various instrumental techniques such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and UV/Visible (UV/VIS) spectrophotometer. The SEM study presented that E. guineense (GE) and D. uncinatum (GN) synthesized gold nanoparticles was below 100 and 300 nm, respectively. The micrographs also presented that E. guineense (GE) synthesized gold particles had irregular round shaped while the D. uncinatum (GN) synthesized nanoparticles had cylindrical shaped. The XRD spectra presented peaks at about 38.1°, 44.43°, 64.6° and 77.64° can be indexed to (111), (200), (220) and (311) orientation, respectively, which confirmed the presence of gold nanoparticles. It means that both E. guineense (GE) and D. uncinatum (GN) synthesized gold nanopar...
Nitrate is an important pollutant, causing eutrophication. Nitrate (NO3-) was analyzed in Pakista... more Nitrate is an important pollutant, causing eutrophication. Nitrate (NO3-) was analyzed in Pakistan at different water sources (hand pump (HP), bore hole (BH) and tube well (TW)) to assess the contamination level caused by NO3-. NO3-concentrations in the HP water samples were 31 mg L-1 to 59 mg L-1, in BH 20 mg L-1 to 79 mg L-1 while in TW water samples the NO3- concentrations were detected in the range of 29 mg L-1 to 55 mg L-1. The association of NO3- with other selected parameter in groundwater can be determined by using statistical approaches. The satisfactory limit of NO3- in the ground-water to be used by human beings is 50 mg L-1. Different physicochemical parameters (pH, electrical conductivity (EC), temperature and dissolved oxygen (DO) were studied in groundwater samples of the research district. Likewise, the pH of all groundwater samples was investigated onsite. The pH of HP groundwater samples was between 7.09 to 7.98, BH groundwater samples pHs were between 6.67 to 7.95 and in TW groundwater samples it was in between 6.67 to 8.16. DO levels were investigated in all groundwater samples collected from the research area. In HP water samples, DO saturation was found from 33.8 to 90.3%, in BH water samples it was 39.3 to 85.4% and 32.6 to 90.7% of saturation in TW water samples. Groundwater samples from HP, BH, and TW in the research area were also tested for electrical conductivity (EC). In HP water sample TDS was found from 620 to 2663 S/cm, in BH water samples it was 617 to 4291 S/cm and in TW water samples it was found in the range of 587 to 2725 S/cm. The Pearson correlation coefficient (r) for groundwater characteristics, water source depth, and water table were calculated. Groundwater samples parameters revealed the strong associations between samples. Hierarchical Cluster Analysis (HCA) was used to categorize samples based on their groundwater quality similarities and to find links between groundwater quality factors. The key relationship of the groundwater for the levels of the HP samples on EC and TDS (r = 1) had a great correlation, while all other parameters correlations were lower (r = 0.40), BH's parameters on WT and WSD (r = 0.57), WT and pH (r = 0.57), EC and DO (r=0.50), DO and TDS (0.50), EC and TDS (r = 1) had a quite high correlation, while all other parameters correlations were less than (r = 0.40), on the other hand, tube well parameters on TDS and EC (r = 1) had a perfect correlation, DO and pH (r = 0.75) parameters correlations were less than (r = 0.40).
At present, wastes management and energy generation are the foremost concerns due to their direct... more At present, wastes management and energy generation are the foremost concerns due to their direct relationship with the biological species and environment. Herein we report utilization of iron rust (inorganic pollutant) as photocatalyst for photodegradation of methylene blue (MB) dye (organic pollutant) under visible light (economic) and water oxidation (energy generation). Iron rust was collected from metallic pipes and calcined in the furnace at 700 °C for 3 h in order to remove moisture/volatile content. The uncalcined and calcined Rust are characterized through scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared (FTIR) analysis, X-Ray Diffraction (XRD) and Thermogravematric analysis (TGA). The morphological study illustrated that the shape of uncalcinedand calcined iron rust is spongy, porous, and agglomerated. The XRD and DLS particle size is in a few hundred-nanometer range.The photodegradation (PD) investigation shows that ...
Tetragonal zirconia was synthesized through microwave modified method and screened for the model ... more Tetragonal zirconia was synthesized through microwave modified method and screened for the model reaction (hydrogenation of octanal to octanol) in self-design microwave reactor in a solvent-free system. The catalyst shows microwave cooperative activity with high selectivity toward desire products. The same reaction was also performed under conventional heating system in Parr reactor. The microwave protocol was found more effective in term of conversion and selectivity under optimal reaction conditions. The enhance activity is due to enormous reducing sites production on the surface triggered by microwave irradiation. Here, the mechanism of acidic site population on the surface was comprehensively investigated and correlated with catalyst efficiency. The gas chromatographic studies revealed the formation of octanol as a major product while other small peaks reflect the formation of byproducts C16 aldol, C16 α, β-unsaturated aldehyde and C24 acetal. Thus, the tetragonal zirconia can be used for the conversion of aldehyde to alcohol under microwave irradiation efficiently.
Photodegradation of organic pollutants is considered to be the most suitable and cheaper techniqu... more Photodegradation of organic pollutants is considered to be the most suitable and cheaper technique to counter decontamination issues.
Journal of Materials Science: Materials in Electronics
Photodegradation of organic pollutants is considered to be the most suitable and cheaper techniqu... more Photodegradation of organic pollutants is considered to be the most suitable and cheaper techniques to counter the contamination issues. Metal nanoparticles are considered to be the most effective heterogenous photocatalysts for the photodegradation of organic pollutants. Besides, CuO oxide nanoparticles are well-known photocatalysts for photocatalytically degrading organic pollutants. Herein, we reported the synthesis of pure copper oxide nanoparticles (CuO NPs) and nanoclay-supported copper oxide nanoparticles (CuO/NC NPs) by facile chemical reduction technique for swift photodegradation of organic dye. The X-ray diffractogram (XRD) has demonstrated a typical monoclinic phase of CuO NPs. The morphological features via scanning electronic microscopy (FESEM) showed agglomerated morphology of CuO NPs with 372.57 ± 1.76 nm average particle size. The micrographs also revealed the homogenous dispersion of CuO NPs over NC surface in CuO/NC nanocomposite. A polydispersity index (PDI) of 0.39 presented slight variation in the particle size of CuO NPs, which is also supported by the results obtained from atomic force microscopy (AFM), FESEM and transmission electron microscopy (TEM). CuO/NC NPs demonstrated outstanding methyl orange degradation over a very short period of time under simulated light. Using CuO/NC NPs, about 97.18% and 95.96% dye degradations were achieved in merely 4 min, under UV and visible light, respectively. The excellent photodegradation efficacy of CuO/NC NPs can be attributed to the homogenous distribution of CuO NPs, which facilitates the generation of photoexcitons (electrons and holes), enhances charge transfer and minimizes the charge recombination. The NC induced the required photostability by providing sufficient space for NPs distribution.
The synergistic effect of binary CdTiO2 and ternary NiCdTiO2 on the photocatalytic efficiency of ... more The synergistic effect of binary CdTiO2 and ternary NiCdTiO2 on the photocatalytic efficiency of TiO2 nanoparticles was investigated. The SEM analysis demonstrates spherical TiO2 NPs of different sizes present in agglomerated form. The structural analysis of the nanocomposites reveals a porous structure for TiO2 with well deposited Cd and Ni NPs. TEM images show NiCdTiO2 nanocomposites as highly crystalline particles having spherical and cubical geometry with an average particle size of 20 nm. The EDX and XRD analysis confirm the purity and anatase phase of TiO2, respectively. Physical features of NiCdTiO2 nanocomposite were determined via BET analysis which shows that the surface area, pore size and pore volume are 61.2 m2/g, 10.6 nm and 0.1 cm3/g, respectively. The absorbance wavelengths of the CdTiO2 and NiCdTiO2 nanocomposites have shown red shift as compared to the neat TiO2 due to coupling with Ni and Cd that results in the enhanced photocatalytic activity. The photocatalytic ...
The conventional chemical methods of nanoparticles synthesis have been effectively replaced by na... more The conventional chemical methods of nanoparticles synthesis have been effectively replaced by nanoparticle synthesis mediated by plants. The current study describes the environmental friendly synthesis of chromium oxide nanoparticles (Cr2O3 NPs) using Erythrophleum guineense plant extract. The synthesis of Cr2O3 NPs was validated by UV/VIS spectroscopy, Energy Dispersive X-Ray (EDX), Scanning Electron Microscopy (SEM), and X-ray diffraction (XRD) studies. The appearance of the Sharpe peak at 460 nm in the UV/Vis spectrum and the colour change caused by surface plasma resonance confirmed the formation of Cr2O3 NPs. The EDX spectrum of Cr2O3 nanoparticles revealed the presence of carbon, oxygen, and chromium, while SEM analysis revealed an irregular round morphology (with a size below 400 nm). In addition, XRD studies suggested their crystalline nature by the characteristic peaks at 34° and 36° and 42° (2Ɵ), respectively. The green synthesized Cr2O3 NPs showed promise as in-vitro cho...
The Nickel oxide nanoparticles (NiO NPs) and Nickel oxide/Nanoclay nanocomposite (NiO/Nc NC) were... more The Nickel oxide nanoparticles (NiO NPs) and Nickel oxide/Nanoclay nanocomposite (NiO/Nc NC) were synthesized by chemical reduction method and used for the photodegradation of Orange II dyes in aqueous solution. The synthesized samples were characterized through SEM, EDX, FTIR and TGA. The SEM analysis presented that the NiO NPs are spherical with irregular shapes and sizes. The size of particles is in the range of 100–400 nm. It was also observed that the NiO NPs are deposited on the surface of Nanoclay. The EDX study confirmed the formation of metal NPs and verify and purity. The FT-IR spectra of NiO and NiO/Nc NC presented peaks at 432 cm−1 and 504 cm−1, which correspond to NiO while peak at 1090–940 cm−1 is due to Si–O stretching vibration of orthosilicate anions and Si–O–Al groups. The photodegradation study illustrated that the NiO NPs and NiO/Nc NC degraded about 93 and 96% Orange II in aqueous medium, respectively within 20 min. The effect of various parameters like initial ...
Removal of heavy metals and dyes from wastewater has received great attention due to scarcity of ... more Removal of heavy metals and dyes from wastewater has received great attention due to scarcity of clean water worldwide. Herein an approach was introduced to attain this goal by employing a single material. Chitosan films were prepared, cross-linked it and utilized for the adsorption of cobalt from aqueous medium. The cobalt adsorbed chitosan was then reutilized as a photocatalyst for the photodegradation of methyl violet dyes. The prepared chitosan, cross-linked chitosan and cobalt adsorbed cross-linked chitosan were characterized through scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). SEM and EDX confirmed the adsorption of cobalt on the cross-linked chitosan. TGA analysis proved the increase in thermal stability with cross-linking while FTIR confirmed the cross-linking of chitosan. Maximum cobalt adsorption of 144 mg/g occurs at 600 ppm salt concentration. The photodegradation s...
Green synthesis has been introduced as an alternative to chemical synthesis due to the serious co... more Green synthesis has been introduced as an alternative to chemical synthesis due to the serious consequences. Metal nanoparticles synthesized through green approach have different pharmaceutical, medical and agricultural applications. The present study followed a green and simple route for the preparation of potentially bioactive gold nanoparticles (Au NPs). Au NPs were prepared via green synthesis approach using crude basic alkaloidal portion of the tuber of Delphinium chitralense. The green synthesized Au NPs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) fourier transform infrared (FTIR), and UV-Visible spectrophotometer. Morphological analysis shows that Au NPs have cubic geometry with different sizes. UV-Vis spectroscopic analysis confirmed the synthesis of Au NPs while XRD proved their pure crystalline phase. The Au NPs showed promising dose dependent inhibition of both AChE and BChE as compared to the c...
Journal of Environmental Health Science and Engineering, 2020
Background Photodegradation of organic pollutants is considered to be the most suitable and cheap... more Background Photodegradation of organic pollutants is considered to be the most suitable and cheaper technique to counter the decontamination issues. Metal nanoparticles are considered to be the most effective heterogeneous photocatalysts for photodegradation of organic pollutants. Besides, iron oxide nanoparticles are well-known photocatalysts for degrading organic pollutants. Methods We reported the synthesis of neat iron oxide nanoparticles (Fe 3 O 4 NPs) and zirconia supported iron oxide nanoparticles (Fe 3 O 4 /ZrO 2 NPs) by facile chemical reduction technique for photodegradation ofa toxic azo dye namely methyl red. Results The XRD and FTIR analysis has demonstrated a crystalline phase Fe 3 O 4 NPs. The morphological features via scanning electronic microscopy (FESEM) suggested agglomerated morphology of neat Fe 3 O 4 NPs with 803.54 ± 5.11 nm average particle size and revealed the uniform morphology and homogenous dispersion of Fe 3 O 4 NPs over ZrO 2 surface in Fe 3 O 4 /ZrO 2 nanocomposite. A polydispersity index (PDI) of 0.47 showed sufficient variations in the particle size of neat Fe 3 O 4 NPs, which is also supported by the results obtained from atomic force microscopy (AFM), FESEM and Transmission Electron Microscopy (TEM). Fe 3 O 4 /ZrO 2 NPs demonstrated efficient methyl red degradation over a short period of time under simulated light and degraded about~91.0 ± 1.0% and 87.0 ± 1.0% dye in 40 min, under UV and visible light, respectively. Conclusion The excellent photodegradation efficacy and sustainability of Fe 3 O 4 /ZrO 2 NPs can be attributed to the homogenous distribution of Fe 3 O 4 NPs over ZrO 2 , which facilitates the generation of photoexcitons (electrons and holes), enhanced charge transfer and minimize the charge recombination.
Photodegradation is the chemical conversion of large, toxic, and complex molecules into non-toxic... more Photodegradation is the chemical conversion of large, toxic, and complex molecules into non-toxic, simpler, and lower molecular weight species due to light exposure. Heterogeneous photocatalysis has sufficient potential to degrade toxic organic pollutants present in wastewater. As industries discharge their effluents containing organic pollutants into natural water bodies, which penetrate into the subsurface through connected pores it is necessary to study this process in natural or tap water. Tap water (TW) is mainly obtained from underground wells having inorganic salts in a minute quantity with a conductivity of 500 μS/cm. TW contains inorganic anions, which affect the photocatalytic activity and photocatalysis process. The aim of this review is to evaluate the effect of TW on the photo-degradation of organic pollutants such as dyes, pharmaceutical products, pesticides, etc., with the support of the literature. The TW had a diverse effect on the photodegradation of organic pollut...
The unavailability of clean drinking water is one of the significant health issues in modern time... more The unavailability of clean drinking water is one of the significant health issues in modern times. Industrial dyes are one of the dominant chemicals that make water unfit for drinking. Among these dyes, methylene blue (MB) is toxic, carcinogenic, and non-biodegradable and can cause a severe threat to human health and environmental safety. It is usually released in natural water sources, which becomes a health threat to human beings and living organisms. Hence, there is a need to develop an environmentally friendly, efficient technology for removing MB from wastewater. Photodegradation is an advanced oxidation process widely used for MB removal. It has the advantages of complete mineralization of dye into simple and nontoxic species with the potential to decrease the processing cost. This review provides a tutorial basis for the readers working in the dye degradation research area. We not only covered the basic principles of the process but also provided a wide range of previously p...
A specific finger-projected fixed-bed reactor (FPFBR) was designed to efficiently utilize magneti... more A specific finger-projected fixed-bed reactor (FPFBR) was designed to efficiently utilize magnetic nanoparticles (MnFe2O4/Bi-MnFe2O4) for a model reaction (hydrogenation of a greenhouse gas, CO2, to valuable products: VPs). Coprecipitation method, with desired modification was used for the preparation of magnetic nanoparticles (MNPs) with controlled shape and size. Eighteen fingers in a single chamber were designed in the fixed-bed reactor’s skeleton; each finger worked as an independent reaction core. Controlled flow of hydrogen and CO2 was continuously provided to preheated reaction cores (catalyst beds) from saturator. One of the major products methanol {(%: Conv, 22/Sel 61)} among VPs was identified and quantified by GC. The efficiency of self-designed reactor was 74% for the direct catalytic hydrogenation of CO2 to valuable organic products.
Nylon 6/6 and ZnO/nylon 6/6 nanocomposite films were prepared by solvent casting method. Morpholo... more Nylon 6/6 and ZnO/nylon 6/6 nanocomposite films were prepared by solvent casting method. Morphological study displayed that ZnO NPs are better dispersed in nylon 6/6. However, some agglomerations were found by the incorporation of high quantities of fillers. The thermal stabilities of neat nylon 6/6 films decreased by addition of nanoparticles (NPs). DSC study shows that the NPs slow down the crystallization rate of neat polymer matrix. POM of Nylon 6/6 upon crystallization showed distinct sized spherulites, which decreased by the incorporation of NPs because of nucleation effect of NPs. The mechanical properties of neat polymer are decreased by addition of ZnO NPs, which might be due to agglomeration of fillers. The neat nylon 6/6 and ZnO/nylon 6/6 nanocomposite were used for the photodegradation of alizarin red (AR) dye, which shows that pure nylon 6/6 degraded about 28% dye while 30% ZnO/Nylon 6/6 degraded about 58.3% dye within 5 h irradiation.
Abstract. The green synthesis of gold nanoparticles (Au NPs) from their precursor was carried out... more Abstract. The green synthesis of gold nanoparticles (Au NPs) from their precursor was carried out using Delphinium uncinatum and Erythrophyleum guineense plants extracts. The Au NPs obtained were characterized by various instrumental techniques such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and UV/Visible (UV/VIS) spectrophotometer. The SEM study presented that E. guineense (GE) and D. uncinatum (GN) synthesized gold nanoparticles was below 100 and 300 nm, respectively. The micrographs also presented that E. guineense (GE) synthesized gold particles had irregular round shaped while the D. uncinatum (GN) synthesized nanoparticles had cylindrical shaped. The XRD spectra presented peaks at about 38.1°, 44.43°, 64.6° and 77.64° can be indexed to (111), (200), (220) and (311) orientation, respectively, which confirmed the presence of gold nanoparticles. It means that both E. guineense (GE) and D. uncinatum (GN) synthesized gold nanopar...
Nitrate is an important pollutant, causing eutrophication. Nitrate (NO3-) was analyzed in Pakista... more Nitrate is an important pollutant, causing eutrophication. Nitrate (NO3-) was analyzed in Pakistan at different water sources (hand pump (HP), bore hole (BH) and tube well (TW)) to assess the contamination level caused by NO3-. NO3-concentrations in the HP water samples were 31 mg L-1 to 59 mg L-1, in BH 20 mg L-1 to 79 mg L-1 while in TW water samples the NO3- concentrations were detected in the range of 29 mg L-1 to 55 mg L-1. The association of NO3- with other selected parameter in groundwater can be determined by using statistical approaches. The satisfactory limit of NO3- in the ground-water to be used by human beings is 50 mg L-1. Different physicochemical parameters (pH, electrical conductivity (EC), temperature and dissolved oxygen (DO) were studied in groundwater samples of the research district. Likewise, the pH of all groundwater samples was investigated onsite. The pH of HP groundwater samples was between 7.09 to 7.98, BH groundwater samples pHs were between 6.67 to 7.95 and in TW groundwater samples it was in between 6.67 to 8.16. DO levels were investigated in all groundwater samples collected from the research area. In HP water samples, DO saturation was found from 33.8 to 90.3%, in BH water samples it was 39.3 to 85.4% and 32.6 to 90.7% of saturation in TW water samples. Groundwater samples from HP, BH, and TW in the research area were also tested for electrical conductivity (EC). In HP water sample TDS was found from 620 to 2663 S/cm, in BH water samples it was 617 to 4291 S/cm and in TW water samples it was found in the range of 587 to 2725 S/cm. The Pearson correlation coefficient (r) for groundwater characteristics, water source depth, and water table were calculated. Groundwater samples parameters revealed the strong associations between samples. Hierarchical Cluster Analysis (HCA) was used to categorize samples based on their groundwater quality similarities and to find links between groundwater quality factors. The key relationship of the groundwater for the levels of the HP samples on EC and TDS (r = 1) had a great correlation, while all other parameters correlations were lower (r = 0.40), BH's parameters on WT and WSD (r = 0.57), WT and pH (r = 0.57), EC and DO (r=0.50), DO and TDS (0.50), EC and TDS (r = 1) had a quite high correlation, while all other parameters correlations were less than (r = 0.40), on the other hand, tube well parameters on TDS and EC (r = 1) had a perfect correlation, DO and pH (r = 0.75) parameters correlations were less than (r = 0.40).
At present, wastes management and energy generation are the foremost concerns due to their direct... more At present, wastes management and energy generation are the foremost concerns due to their direct relationship with the biological species and environment. Herein we report utilization of iron rust (inorganic pollutant) as photocatalyst for photodegradation of methylene blue (MB) dye (organic pollutant) under visible light (economic) and water oxidation (energy generation). Iron rust was collected from metallic pipes and calcined in the furnace at 700 °C for 3 h in order to remove moisture/volatile content. The uncalcined and calcined Rust are characterized through scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared (FTIR) analysis, X-Ray Diffraction (XRD) and Thermogravematric analysis (TGA). The morphological study illustrated that the shape of uncalcinedand calcined iron rust is spongy, porous, and agglomerated. The XRD and DLS particle size is in a few hundred-nanometer range.The photodegradation (PD) investigation shows that ...
Tetragonal zirconia was synthesized through microwave modified method and screened for the model ... more Tetragonal zirconia was synthesized through microwave modified method and screened for the model reaction (hydrogenation of octanal to octanol) in self-design microwave reactor in a solvent-free system. The catalyst shows microwave cooperative activity with high selectivity toward desire products. The same reaction was also performed under conventional heating system in Parr reactor. The microwave protocol was found more effective in term of conversion and selectivity under optimal reaction conditions. The enhance activity is due to enormous reducing sites production on the surface triggered by microwave irradiation. Here, the mechanism of acidic site population on the surface was comprehensively investigated and correlated with catalyst efficiency. The gas chromatographic studies revealed the formation of octanol as a major product while other small peaks reflect the formation of byproducts C16 aldol, C16 α, β-unsaturated aldehyde and C24 acetal. Thus, the tetragonal zirconia can be used for the conversion of aldehyde to alcohol under microwave irradiation efficiently.
Photodegradation of organic pollutants is considered to be the most suitable and cheaper techniqu... more Photodegradation of organic pollutants is considered to be the most suitable and cheaper technique to counter decontamination issues.
Journal of Materials Science: Materials in Electronics
Photodegradation of organic pollutants is considered to be the most suitable and cheaper techniqu... more Photodegradation of organic pollutants is considered to be the most suitable and cheaper techniques to counter the contamination issues. Metal nanoparticles are considered to be the most effective heterogenous photocatalysts for the photodegradation of organic pollutants. Besides, CuO oxide nanoparticles are well-known photocatalysts for photocatalytically degrading organic pollutants. Herein, we reported the synthesis of pure copper oxide nanoparticles (CuO NPs) and nanoclay-supported copper oxide nanoparticles (CuO/NC NPs) by facile chemical reduction technique for swift photodegradation of organic dye. The X-ray diffractogram (XRD) has demonstrated a typical monoclinic phase of CuO NPs. The morphological features via scanning electronic microscopy (FESEM) showed agglomerated morphology of CuO NPs with 372.57 ± 1.76 nm average particle size. The micrographs also revealed the homogenous dispersion of CuO NPs over NC surface in CuO/NC nanocomposite. A polydispersity index (PDI) of 0.39 presented slight variation in the particle size of CuO NPs, which is also supported by the results obtained from atomic force microscopy (AFM), FESEM and transmission electron microscopy (TEM). CuO/NC NPs demonstrated outstanding methyl orange degradation over a very short period of time under simulated light. Using CuO/NC NPs, about 97.18% and 95.96% dye degradations were achieved in merely 4 min, under UV and visible light, respectively. The excellent photodegradation efficacy of CuO/NC NPs can be attributed to the homogenous distribution of CuO NPs, which facilitates the generation of photoexcitons (electrons and holes), enhances charge transfer and minimizes the charge recombination. The NC induced the required photostability by providing sufficient space for NPs distribution.
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Papers by Idrees Khan