Neway Belachew - Academia.edu (original) (raw)

Papers by Neway Belachew

Journal of Molecular Liquids

Supplemental material, Supplemental_material for RSM-BBD Optimization of Fenton-Like Degradation ... more Supplemental material, Supplemental_material for RSM-BBD Optimization of Fenton-Like Degradation of 4-Nitrophenol Using Magnetite Impregnated Kaolin by Neway Belachew, Redeat Fekadu and Amare Ayalew Abebe in Air, Soil and Water Research

RSC Advances, 2021

Herein, 3D mesoporous structures assembled from monoclinic M-phase VO2 nanoflakes were successful... more Herein, 3D mesoporous structures assembled from monoclinic M-phase VO2 nanoflakes were successfully synthesized for enhanced thermochromic performance.

RSC Advances, 2021

In this study, we report a green synthesis of MoS2 nanosheets (NSs) using a facile hydrothermal t... more In this study, we report a green synthesis of MoS2 nanosheets (NSs) using a facile hydrothermal technique in the presence of l-cysteine.

Silicon, 2021

In this study, we have reported a facile preparation of zeolite 4A from Ethiopia kaolin for the a... more In this study, we have reported a facile preparation of zeolite 4A from Ethiopia kaolin for the adsorptive removal of methylene blue (MB) dye. The formation of highly crystalline and pure phase zeolite 4A with cubic morphology was confirmed by powder X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis. The efficiency of zeolite 4A for abatement of MB was investigated at varying adsorption parameters. Response surface methodology coupled with Box Behnken Design (RSM-BBD) was employed to optimize adsorption parameters. High regression (R2 = 0.9947) and the low probability (p value <0.0001) values signify the validity of the quadratic model to predict the removal (%) of MB. The maximum MB removal (%) was 99.37% at the optimum combination of 50 mL of 10 mg/L of MB, 39.05 mg zeolite 4A, and 179.82 contact time (min). The adjusted R-square (R2adj) and standard deviations (SD) were validated the best fitting of pseudo-second-order kinetics and the Langmuir isotherm model for experimental values. The maximum adsorption capacity (Qmax) of zeolite 4A towards MB was found to be 44.35 mg g−1. Electrostatic interaction, hydrogen bond, and n to π bond formation are predicted to be the plausible interaction mechanism of MB to the surface of zeolite 4A. The Fukui function and vibration analysis based on the density functional theory (DFT) further strengthened the proposed mechanism.

RSC Advances, 2021

A highly efficient visible light active polyaniline (PANI)/Ag composites grafted reduced graphene... more A highly efficient visible light active polyaniline (PANI)/Ag composites grafted reduced graphene oxide (rGO–Ag/PANI) was prepared for the efficient photocatalytic degradation of paracetamol.

Journal of Fluorescence, 2021

Carbon quantum dots (CQD) as the result of their exceptional physical and chemical properties sho... more Carbon quantum dots (CQD) as the result of their exceptional physical and chemical properties show tremendous potential in various field of applications like cell imaging and doping of CQDs with elements like nitrogen and phosphorous increase its fluorescence property. Herein, we have synthesized fluorescent nitrogen and phosphorous codoped carbon quantum dots (NPCQDs) via a one-pot hydrothermal method. Sesame oil, L-Aspartic acid, and phosphoric acid were used as carbon, nitrogen, and phosphorous sources, respectively. UV-Vis spectrophotometer, fluorescence spectrometer, Fourier transform infrared spectrometer (FTIR), X-ray diffraction spectrometer (XRD), field emission scanning microscopy (FESEM), and transmission electron microscopy (TEM) were employed to characterize the synthesized fluorescent NPCQDs. The as-synthesized NPCQDs with a particle size of 4.7 nm possess excellent water solubility, high fluorescence with high quantum yield (46%), high ionic stability, and resistance to photobleaching. MTT assay indicated the biocompatibility of NPCQDs and it was used for multicolor live-cell imaging. Besides, the NPCQDs show an effective probe of iron ions (Fe3+) in an aqueous solution with a high degree of sensitivity and selectivity. The DPPH assay showed its good antioxidant activity.

Applied Water Science, 2021

L-Aspartic acid (L-Asp) functionalized magnetite nanoparticles (Fe3O4 NPs) were synthesized throu... more L-Aspartic acid (L-Asp) functionalized magnetite nanoparticles (Fe3O4 NPs) were synthesized through a facile co-precipitation method using L-Asp as a capping agent. UV–Vis, FTIR, XRD, SEM, EDS, TEM, and VSM techniques were used to investigate the formation, morphology, elemental composition, and magnetic properties of the synthesized Fe3O4 NPs. Highly crystalline and spherical shaped pure phase Fe3O4 NPs were successfully synthesized using amino acid as a capping agent. The magnetic measurement analysis confirms the superparamagnetic nature of the synthesized L-Asp capped Fe3O4 NPs. The adsorption efficiency of L-Asp capped Fe3O4 NPs was assessed by the removal of Rhodamine B (RhB). The optimum removal efficiency was found to be 7.7 mg g−1 using 1 mg mL−1 adsorbent, and 30 mg L−1 RhB at pH 7 and 25 °C. The regression (R2adj) and standard deviation (SD) analysis were used to validate both kinetic and isotherm models. Avrami fractional-order and Liu models were selected as the best ki...

ACS Omega, 2020

In this manuscript, the author name "Kaloth Basavaiah" must be corrected as "Keloth Basavaiah" an... more In this manuscript, the author name "Kaloth Basavaiah" must be corrected as "Keloth Basavaiah" and his name must come last in author list order. This is reflected in the authorship of this Correction.

American Journal of Life Sciences, 2017

Over one billion people on Earth do not have access to clean drinking water. Several nonprofit an... more Over one billion people on Earth do not have access to clean drinking water. Several nonprofit and government organizations are promoting low cost, household methods for water purification [1, 2]. One of best alternative approach for equator and temperate region including Ethiopia is solar water disinfection or SODIS. The previous work done at Shoarobit and Surrounding Rural Kebeles, shows that SODIS treatment with clear 1.5 bottles and low turbidity, disinfection is efficient at the end of six hours [3]. However frequently use of the same bottle cause for scratch on the surface of the bottle. Hence this paper addresses effect of bottle scratch and lemon juice (as a catalyst) on solar disinfection. Different level of scratches, Less scratch bottle (LSB), Slightly Scratch Bottle (SSB) and Highly Scratch Bottle (HSB) was analyzed. Since SODIS treatment is mainly due to UV radiation, causes for lysis the DNA of microorganisms, if it is not passes through the surface of the bottle the method became inefficient. From the result it was obtained that there is significance statistical difference between densities of scratched bottles. The disinfection efficiency different scratch bottle is decreases as the following order LSB > SSB > HSB. In addition it was tested that effect of lemon juice on solar disinfection. The pH decrease (acidity increase) and solar disinfection has a synergic effect. This was shown the disinfection efficiency increase accordingly the following pH order: pH = 3 > pH = 5 > pH = 7. In conclusion at the end of six hours almost all bacterial colonies was disinfected in all forms of scratching bottles and this disinfection efficiency of the method enhance with adding lemon juice.

RSC Advances, 2020

In this study, we have reported selective synthesis of γ-Bi2M2O6 NPs under different pH condition... more In this study, we have reported selective synthesis of γ-Bi2M2O6 NPs under different pH conditions for photocatalytic degradation of methylene blue (MB), reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) and antimicrobial activities.

Journal of Environmental Chemical Engineering, 2020

Abstract We have reported a facile, green synthesis of reduced graphene oxide (RGO) grafted Ag/Zn... more Abstract We have reported a facile, green synthesis of reduced graphene oxide (RGO) grafted Ag/ZnO (RGO-Ag/ZnO) nanocomposite in the presence of L-Methionine (L-Met) for synergetic photocatalytic degradation of methylene blue (MB) and antibacterial activities. L-Met shows an excellent efficiency as stabilizing and reducing agents for the synthesis of both Ag NPs and RGO. The successful synthesis of pure phase L-Met-RGO-Ag/ZnO was confirmed by XRD. According to UV-DRS analysis, the doping of Ag resulted in a decrease bandgap energy of ZnO from 3.34 eV to 3.18 eV. The mixed morphologies of the nanocomposite were studied by SEM and TEM. The photocatalytic degradation efficiency of L-Met-RGO-Ag/ZnO towards MB dye was investigated at varying initial concentrations of MB dye, H2O2, and ultrasonication. The optimum degradation efficiency of the nanocomposite (50 mg) at room temperature (25 °C) was found to be 99% with an initial MB dye concentration of 10 mg/L and 120 min contact time. The fast degradation of MB dye was observed in the presence of H2O2. The ultrasonication of the catalyst vanishes the synergetic interface of the nanocomposite, as a result, poor photocatalytic performance (85%) was observed even at a long period of contact time (210 min). Moreover, RGO-Ag/ZnO nanocomposites have shown strong antibacterial activity against both Gram-positive bacteria (B. Subtilis) and Gram-negative bacteria (E. coli). In conclusion, RGO-Ag/ZnO nanocomposite shows a promising photocatalyst for the degradation of organic dyes and antibacterial activities.

International Journal of Advanced Research, Mar 31, 2018

ACS Omega, 2020

In this study, we report a green and economical hydrothermal synthesis of fluorescent-nitrogen-do... more In this study, we report a green and economical hydrothermal synthesis of fluorescent-nitrogen-doped carbon quantum dots (NCQDs) using citrus lemon as a carbon source. The prepared NCQDs possess high water solubility, high ionic stability, resistance to photobleaching, and bright blue color under ultraviolet radiation with a high quantum yield (∼31%). Highresolution transmission electron microscopy (HRTEM) results show that the prepared NCQDs have a narrow size distribution (1−6 nm) with an average particle size of 3 nm. The mercury ion (Hg 2+) sensing efficiency of the NCQDs was studied, and the result indicated that the material has high sensitivity, high precision, and good selectivity for Hg 2+. The limit of detection (LOD) is 5.3 nM and the limit of quantification (LOQ) is 18.3 nM at a 99% confidence level. The cytotoxicity was evaluated using MCF7 cells, and the cell viabilities were determined to be greater than 88% upon the addition of NCQDs over a wide concentration range from 0 to 2 mg/mL. Based on the low cytotoxicity, good biocompatibility, and other revealed interesting merits, we also applied the prepared NCQDs as an effective fluorescent probe for multicolor live cell imaging.

Emergent Materials, 2020

In this work, Fe 3 O 4 nanoparticles impregnated N-doped RGO (Fe 3 O 4-N-RGO) nanocomposite was s... more In this work, Fe 3 O 4 nanoparticles impregnated N-doped RGO (Fe 3 O 4-N-RGO) nanocomposite was synthesized through one-pot electrostatic self-assembly of magnetite nanoparticles (Fe 3 O 4 NPs) on N-doped RGO sheet in the presence of L-serine (L-Ser) as a surface functionalizing and reducing agent. The surface property, structure, morphology, and magnetic properties of as-prepared Fe 3 O 4-N-RGO nanocomposite were characterized by FTIR spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), vibrating sample magnetometer (VSM), and electron paramagnetic resonance spectroscopy (EPRS). The XRD results were indicated the formation of high crystalline spinel type Fe 3 O 4 NPs. The Fe 3 O 4 nanoparticles with average sizes of 12 nm were formed uniformly on reduced graphene sheets. The Fe 3 O 4-N-RGO nanocomposite was used as an adsorbent to remove Rhodamine B dye from aqueous solution. The nanocomposite shows excellent ability to adsorb organic pollutants and can be easily manipulated in a magnetic field for separation. The results suggest that Fe 3 O 4-N-RGO nanocomposite has great potential for efficient removal of organic dyes pollutants from aqueous solution.

Applied Water Science, 2019

In the current work, we have reported a cationic surfactant-modified Ethiopian kaolin for improve... more In the current work, we have reported a cationic surfactant-modified Ethiopian kaolin for improved adsorption of Cr(VI) from aqueous solution. The raw kaolin was modified by treating with CTAB to enhance the adsorption properties. The crystal structure and vibrational analysis of CTAB–kaolin were investigated by Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (p-XRD) techniques. The successful modification of kaolin by CTAB through intercalation and coating was investigated by XRD and FTIR. p-XRD confirms the raw kaolin obtained from Belesa, Tigo kebele is kaolinite mineral. The study has also focused on the application of kaolin–CTAB for adsorption of hexavalent chromium. The percent removal of Cr(VI) was investigated at different parameters such as pH, contact time, concentration of Cr(VI) and adsorbent dosage. CTAB–kaolin shows 99% removal of Cr(VI) at the adsorption equilibrium (time = 180 min, 100 mg CTAB–kaolin, 10 ppm/100 ml). The Langmuir and Freu...

RSC Advances, 2019

Herein, we have reported a facile and green synthesis approach of Ag NP decorated reduced graphen... more Herein, we have reported a facile and green synthesis approach of Ag NP decorated reduced graphene oxide (RGO) through an in situ self-assembly method in the presence of l-methionine (l-Met) as reducing and stabilizing agent.

RSC Advances, 2019

We report a facile one-pot green synthesis of zinc oxide (ZnO) nanostructures using aqueous leaf ... more We report a facile one-pot green synthesis of zinc oxide (ZnO) nanostructures using aqueous leaf extract of Dolichos Lablab L. as the reducing and capping agent.

RSC Advances, 2019

We report a facile one-pot green synthesis of zinc oxide (ZnO) nanostructures using aqueous leaf ... more We report a facile one-pot green synthesis of zinc oxide (ZnO) nanostructures using aqueous leaf extract of Dolichos Lablab L. as the reducing and capping agent.

Silicon, 2019

Recently, magnetic separation of adsorbent materials has attracted much attention for abatement o... more Recently, magnetic separation of adsorbent materials has attracted much attention for abatement of water pollutants. Due to the strong magnetic property and environmental beneficial behavior Fe 3 O 4 NPs were used to modify local bentonite clay. The prepared magnetite intercalated Bentonite clay composite (Fe 3 O 4 -AC) structure and magnetic property were confirmed by powder X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). The prepared Fe 3 O 4 -AC composite has shown a superior adsorption efficiency to Congo red (CR) dye over acid activated bentonite clay (AC). The enhanced adsorption of the Fe 3 O 4 NPs intercalated in the layer of bentonite could be ascribed to the enhanced surface area and the prevention of the activated clay agglomeration. The optimum removal efficiency was analyzed using Response Surface Methodology (RSM) based Box-Benhken Design (BBD). The optimum conditions for maximum adsorption % removal were found to 94.9% at 105 min, 0.6 g Fe 3 O 4 -AC composite, 10 mg. L −1 , and pH =4. The adsorption isotherms and Kinetics process were indicated that the experimental data are well fitted to Langmuir and pseudo-second-order models. Graphical Abstract

Journal of Molecular Liquids

Supplemental material, Supplemental_material for RSM-BBD Optimization of Fenton-Like Degradation ... more Supplemental material, Supplemental_material for RSM-BBD Optimization of Fenton-Like Degradation of 4-Nitrophenol Using Magnetite Impregnated Kaolin by Neway Belachew, Redeat Fekadu and Amare Ayalew Abebe in Air, Soil and Water Research

RSC Advances, 2021

Herein, 3D mesoporous structures assembled from monoclinic M-phase VO2 nanoflakes were successful... more Herein, 3D mesoporous structures assembled from monoclinic M-phase VO2 nanoflakes were successfully synthesized for enhanced thermochromic performance.

RSC Advances, 2021

In this study, we report a green synthesis of MoS2 nanosheets (NSs) using a facile hydrothermal t... more In this study, we report a green synthesis of MoS2 nanosheets (NSs) using a facile hydrothermal technique in the presence of l-cysteine.

Silicon, 2021

In this study, we have reported a facile preparation of zeolite 4A from Ethiopia kaolin for the a... more In this study, we have reported a facile preparation of zeolite 4A from Ethiopia kaolin for the adsorptive removal of methylene blue (MB) dye. The formation of highly crystalline and pure phase zeolite 4A with cubic morphology was confirmed by powder X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis. The efficiency of zeolite 4A for abatement of MB was investigated at varying adsorption parameters. Response surface methodology coupled with Box Behnken Design (RSM-BBD) was employed to optimize adsorption parameters. High regression (R2 = 0.9947) and the low probability (p value <0.0001) values signify the validity of the quadratic model to predict the removal (%) of MB. The maximum MB removal (%) was 99.37% at the optimum combination of 50 mL of 10 mg/L of MB, 39.05 mg zeolite 4A, and 179.82 contact time (min). The adjusted R-square (R2adj) and standard deviations (SD) were validated the best fitting of pseudo-second-order kinetics and the Langmuir isotherm model for experimental values. The maximum adsorption capacity (Qmax) of zeolite 4A towards MB was found to be 44.35 mg g−1. Electrostatic interaction, hydrogen bond, and n to π bond formation are predicted to be the plausible interaction mechanism of MB to the surface of zeolite 4A. The Fukui function and vibration analysis based on the density functional theory (DFT) further strengthened the proposed mechanism.

RSC Advances, 2021

A highly efficient visible light active polyaniline (PANI)/Ag composites grafted reduced graphene... more A highly efficient visible light active polyaniline (PANI)/Ag composites grafted reduced graphene oxide (rGO–Ag/PANI) was prepared for the efficient photocatalytic degradation of paracetamol.

Journal of Fluorescence, 2021

Carbon quantum dots (CQD) as the result of their exceptional physical and chemical properties sho... more Carbon quantum dots (CQD) as the result of their exceptional physical and chemical properties show tremendous potential in various field of applications like cell imaging and doping of CQDs with elements like nitrogen and phosphorous increase its fluorescence property. Herein, we have synthesized fluorescent nitrogen and phosphorous codoped carbon quantum dots (NPCQDs) via a one-pot hydrothermal method. Sesame oil, L-Aspartic acid, and phosphoric acid were used as carbon, nitrogen, and phosphorous sources, respectively. UV-Vis spectrophotometer, fluorescence spectrometer, Fourier transform infrared spectrometer (FTIR), X-ray diffraction spectrometer (XRD), field emission scanning microscopy (FESEM), and transmission electron microscopy (TEM) were employed to characterize the synthesized fluorescent NPCQDs. The as-synthesized NPCQDs with a particle size of 4.7 nm possess excellent water solubility, high fluorescence with high quantum yield (46%), high ionic stability, and resistance to photobleaching. MTT assay indicated the biocompatibility of NPCQDs and it was used for multicolor live-cell imaging. Besides, the NPCQDs show an effective probe of iron ions (Fe3+) in an aqueous solution with a high degree of sensitivity and selectivity. The DPPH assay showed its good antioxidant activity.

Applied Water Science, 2021

L-Aspartic acid (L-Asp) functionalized magnetite nanoparticles (Fe3O4 NPs) were synthesized throu... more L-Aspartic acid (L-Asp) functionalized magnetite nanoparticles (Fe3O4 NPs) were synthesized through a facile co-precipitation method using L-Asp as a capping agent. UV–Vis, FTIR, XRD, SEM, EDS, TEM, and VSM techniques were used to investigate the formation, morphology, elemental composition, and magnetic properties of the synthesized Fe3O4 NPs. Highly crystalline and spherical shaped pure phase Fe3O4 NPs were successfully synthesized using amino acid as a capping agent. The magnetic measurement analysis confirms the superparamagnetic nature of the synthesized L-Asp capped Fe3O4 NPs. The adsorption efficiency of L-Asp capped Fe3O4 NPs was assessed by the removal of Rhodamine B (RhB). The optimum removal efficiency was found to be 7.7 mg g−1 using 1 mg mL−1 adsorbent, and 30 mg L−1 RhB at pH 7 and 25 °C. The regression (R2adj) and standard deviation (SD) analysis were used to validate both kinetic and isotherm models. Avrami fractional-order and Liu models were selected as the best ki...

ACS Omega, 2020

In this manuscript, the author name "Kaloth Basavaiah" must be corrected as "Keloth Basavaiah" an... more In this manuscript, the author name "Kaloth Basavaiah" must be corrected as "Keloth Basavaiah" and his name must come last in author list order. This is reflected in the authorship of this Correction.

American Journal of Life Sciences, 2017

Over one billion people on Earth do not have access to clean drinking water. Several nonprofit an... more Over one billion people on Earth do not have access to clean drinking water. Several nonprofit and government organizations are promoting low cost, household methods for water purification [1, 2]. One of best alternative approach for equator and temperate region including Ethiopia is solar water disinfection or SODIS. The previous work done at Shoarobit and Surrounding Rural Kebeles, shows that SODIS treatment with clear 1.5 bottles and low turbidity, disinfection is efficient at the end of six hours [3]. However frequently use of the same bottle cause for scratch on the surface of the bottle. Hence this paper addresses effect of bottle scratch and lemon juice (as a catalyst) on solar disinfection. Different level of scratches, Less scratch bottle (LSB), Slightly Scratch Bottle (SSB) and Highly Scratch Bottle (HSB) was analyzed. Since SODIS treatment is mainly due to UV radiation, causes for lysis the DNA of microorganisms, if it is not passes through the surface of the bottle the method became inefficient. From the result it was obtained that there is significance statistical difference between densities of scratched bottles. The disinfection efficiency different scratch bottle is decreases as the following order LSB > SSB > HSB. In addition it was tested that effect of lemon juice on solar disinfection. The pH decrease (acidity increase) and solar disinfection has a synergic effect. This was shown the disinfection efficiency increase accordingly the following pH order: pH = 3 > pH = 5 > pH = 7. In conclusion at the end of six hours almost all bacterial colonies was disinfected in all forms of scratching bottles and this disinfection efficiency of the method enhance with adding lemon juice.

RSC Advances, 2020

In this study, we have reported selective synthesis of γ-Bi2M2O6 NPs under different pH condition... more In this study, we have reported selective synthesis of γ-Bi2M2O6 NPs under different pH conditions for photocatalytic degradation of methylene blue (MB), reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) and antimicrobial activities.

Journal of Environmental Chemical Engineering, 2020

Abstract We have reported a facile, green synthesis of reduced graphene oxide (RGO) grafted Ag/Zn... more Abstract We have reported a facile, green synthesis of reduced graphene oxide (RGO) grafted Ag/ZnO (RGO-Ag/ZnO) nanocomposite in the presence of L-Methionine (L-Met) for synergetic photocatalytic degradation of methylene blue (MB) and antibacterial activities. L-Met shows an excellent efficiency as stabilizing and reducing agents for the synthesis of both Ag NPs and RGO. The successful synthesis of pure phase L-Met-RGO-Ag/ZnO was confirmed by XRD. According to UV-DRS analysis, the doping of Ag resulted in a decrease bandgap energy of ZnO from 3.34 eV to 3.18 eV. The mixed morphologies of the nanocomposite were studied by SEM and TEM. The photocatalytic degradation efficiency of L-Met-RGO-Ag/ZnO towards MB dye was investigated at varying initial concentrations of MB dye, H2O2, and ultrasonication. The optimum degradation efficiency of the nanocomposite (50 mg) at room temperature (25 °C) was found to be 99% with an initial MB dye concentration of 10 mg/L and 120 min contact time. The fast degradation of MB dye was observed in the presence of H2O2. The ultrasonication of the catalyst vanishes the synergetic interface of the nanocomposite, as a result, poor photocatalytic performance (85%) was observed even at a long period of contact time (210 min). Moreover, RGO-Ag/ZnO nanocomposites have shown strong antibacterial activity against both Gram-positive bacteria (B. Subtilis) and Gram-negative bacteria (E. coli). In conclusion, RGO-Ag/ZnO nanocomposite shows a promising photocatalyst for the degradation of organic dyes and antibacterial activities.

International Journal of Advanced Research, Mar 31, 2018

ACS Omega, 2020

In this study, we report a green and economical hydrothermal synthesis of fluorescent-nitrogen-do... more In this study, we report a green and economical hydrothermal synthesis of fluorescent-nitrogen-doped carbon quantum dots (NCQDs) using citrus lemon as a carbon source. The prepared NCQDs possess high water solubility, high ionic stability, resistance to photobleaching, and bright blue color under ultraviolet radiation with a high quantum yield (∼31%). Highresolution transmission electron microscopy (HRTEM) results show that the prepared NCQDs have a narrow size distribution (1−6 nm) with an average particle size of 3 nm. The mercury ion (Hg 2+) sensing efficiency of the NCQDs was studied, and the result indicated that the material has high sensitivity, high precision, and good selectivity for Hg 2+. The limit of detection (LOD) is 5.3 nM and the limit of quantification (LOQ) is 18.3 nM at a 99% confidence level. The cytotoxicity was evaluated using MCF7 cells, and the cell viabilities were determined to be greater than 88% upon the addition of NCQDs over a wide concentration range from 0 to 2 mg/mL. Based on the low cytotoxicity, good biocompatibility, and other revealed interesting merits, we also applied the prepared NCQDs as an effective fluorescent probe for multicolor live cell imaging.

Emergent Materials, 2020

In this work, Fe 3 O 4 nanoparticles impregnated N-doped RGO (Fe 3 O 4-N-RGO) nanocomposite was s... more In this work, Fe 3 O 4 nanoparticles impregnated N-doped RGO (Fe 3 O 4-N-RGO) nanocomposite was synthesized through one-pot electrostatic self-assembly of magnetite nanoparticles (Fe 3 O 4 NPs) on N-doped RGO sheet in the presence of L-serine (L-Ser) as a surface functionalizing and reducing agent. The surface property, structure, morphology, and magnetic properties of as-prepared Fe 3 O 4-N-RGO nanocomposite were characterized by FTIR spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), vibrating sample magnetometer (VSM), and electron paramagnetic resonance spectroscopy (EPRS). The XRD results were indicated the formation of high crystalline spinel type Fe 3 O 4 NPs. The Fe 3 O 4 nanoparticles with average sizes of 12 nm were formed uniformly on reduced graphene sheets. The Fe 3 O 4-N-RGO nanocomposite was used as an adsorbent to remove Rhodamine B dye from aqueous solution. The nanocomposite shows excellent ability to adsorb organic pollutants and can be easily manipulated in a magnetic field for separation. The results suggest that Fe 3 O 4-N-RGO nanocomposite has great potential for efficient removal of organic dyes pollutants from aqueous solution.

Applied Water Science, 2019

In the current work, we have reported a cationic surfactant-modified Ethiopian kaolin for improve... more In the current work, we have reported a cationic surfactant-modified Ethiopian kaolin for improved adsorption of Cr(VI) from aqueous solution. The raw kaolin was modified by treating with CTAB to enhance the adsorption properties. The crystal structure and vibrational analysis of CTAB–kaolin were investigated by Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (p-XRD) techniques. The successful modification of kaolin by CTAB through intercalation and coating was investigated by XRD and FTIR. p-XRD confirms the raw kaolin obtained from Belesa, Tigo kebele is kaolinite mineral. The study has also focused on the application of kaolin–CTAB for adsorption of hexavalent chromium. The percent removal of Cr(VI) was investigated at different parameters such as pH, contact time, concentration of Cr(VI) and adsorbent dosage. CTAB–kaolin shows 99% removal of Cr(VI) at the adsorption equilibrium (time = 180 min, 100 mg CTAB–kaolin, 10 ppm/100 ml). The Langmuir and Freu...

RSC Advances, 2019

Herein, we have reported a facile and green synthesis approach of Ag NP decorated reduced graphen... more Herein, we have reported a facile and green synthesis approach of Ag NP decorated reduced graphene oxide (RGO) through an in situ self-assembly method in the presence of l-methionine (l-Met) as reducing and stabilizing agent.

RSC Advances, 2019

We report a facile one-pot green synthesis of zinc oxide (ZnO) nanostructures using aqueous leaf ... more We report a facile one-pot green synthesis of zinc oxide (ZnO) nanostructures using aqueous leaf extract of Dolichos Lablab L. as the reducing and capping agent.

RSC Advances, 2019

We report a facile one-pot green synthesis of zinc oxide (ZnO) nanostructures using aqueous leaf ... more We report a facile one-pot green synthesis of zinc oxide (ZnO) nanostructures using aqueous leaf extract of Dolichos Lablab L. as the reducing and capping agent.

Silicon, 2019

Recently, magnetic separation of adsorbent materials has attracted much attention for abatement o... more Recently, magnetic separation of adsorbent materials has attracted much attention for abatement of water pollutants. Due to the strong magnetic property and environmental beneficial behavior Fe 3 O 4 NPs were used to modify local bentonite clay. The prepared magnetite intercalated Bentonite clay composite (Fe 3 O 4 -AC) structure and magnetic property were confirmed by powder X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). The prepared Fe 3 O 4 -AC composite has shown a superior adsorption efficiency to Congo red (CR) dye over acid activated bentonite clay (AC). The enhanced adsorption of the Fe 3 O 4 NPs intercalated in the layer of bentonite could be ascribed to the enhanced surface area and the prevention of the activated clay agglomeration. The optimum removal efficiency was analyzed using Response Surface Methodology (RSM) based Box-Benhken Design (BBD). The optimum conditions for maximum adsorption % removal were found to 94.9% at 105 min, 0.6 g Fe 3 O 4 -AC composite, 10 mg. L −1 , and pH =4. The adsorption isotherms and Kinetics process were indicated that the experimental data are well fitted to Langmuir and pseudo-second-order models. Graphical Abstract