The electrochemical reduction of carbon dioxide (CO2) on copper electrode derived from cupric oxi... more The electrochemical reduction of carbon dioxide (CO2) on copper electrode derived from cupric oxide (CuO), named oxide derived copper (ODCu), was studied thoroughly in the potential range of −1.0 V to −1.5 V versus RHE. The CuO nanoparticles were prepared by the hydrothermal method. The ODCu electrode was used for carbon dioxide reduction and the results revealed that this electrode is highly selective for C2+ products with enhanced current density at significantly less overpotential. This catalyst shifts the selectivity towards C2+ products with the highest Faradaic efficiency up to 58% at −0.95 V. In addition, C2 product formation at the lowest onset potential of −0.1 V is achieved with the proposed catalyst. X-ray diffraction and scanning electron microscopy revealed the reduction of CuO to Cu (111) nanoparticles during the CO2 RR. The intrinsic property of the synthesized catalyst and its surface reduction are suggested to induce sites or edges for facilitating the dimerization ...
A highly sensitive electrochemical sensor based on immobilization of a newly synthesized urea fun... more A highly sensitive electrochemical sensor based on immobilization of a newly synthesized urea functionality containing surfactant, 1-(2, 4-dinitrophenyl)-dodecanoylthiourea (DAN), possessing soil fertility enhancing characteristics, was developed for the detection of Hg(II) using cyclic, square wave and differential pulse voltammetry. Under suitable experimental conditions, calibration plot with a good linearity up to 2 µg/L was obtained with a detection limit of 0.64 µg/L and sensitivity of 0.164 µAL/µg in doubly distilled water at accumulation time of 360 sec using square wave voltammetry. The proposed method was also used for the determination of Hg (II) in drinking and tap water samples with very good recovery data and relative standard deviation of less than 3.5%. The designed sensor exhibited remarkable electrocatalytic effect by dramatically boosting the signal of the analyte as compared to the bare electrode. Computational studies of the interaction of DAN and mercury were also performed. The theoretical results were found in good agreement with the experimental findings.
Abstract A highly sensitive electrochemical sensor using a novel surfactant 1-cyclohexyl-3-dodeca... more Abstract A highly sensitive electrochemical sensor using a novel surfactant 1-cyclohexyl-3-dodecanoylthiourea (CDT) as a recognition layer was developed for the detection of Cd 2+ and Hg 2+ using electrochemical impedance spectroscopy, chronocoulometry and a number of voltammetric techniques such as cyclic, square wave and differential pulse stripping voltammetry. For optimization, the effect of several experimental factors such as concentration of the surfactant, scan rate, pH, accumulation time, number of cycles and supporting electrolytes were investigated. The limits of detection quite lower than the danger level suggested by world health organization (WHO), Environmental protection agency (EPA) and European water quality (EWQ) suggested the suitability of our designed sensor for monitoring metal based water toxins. Theoretical studies carried out for the calculation of interaction energy of CDT with Hg 2+ and Cd 2+ supported the experimental findings. The validity of the proposed method for real water sample analysis was ensured from reasonable percentage recoveries and less than 4% RSD values. Moreover, the designed sensor demonstrated excellent discrimination ability for the target analytes in the presence of interfering agents.
The study was conducted to evaluate the effect of artificial feed and adding organic manures to t... more The study was conducted to evaluate the effect of artificial feed and adding organic manures to the earthen ponds on the growth and body composition of genetically improved farmed tilapia (GIFT). A total of 160 fish were stocked in each of the two ponds for 90 days. Fish in both ponds were fed with supplementary feed containing 30% crude protein at 4% body weight. Pond 1 was fertilized using cow dung and poultry manure while pond 2, received no fertilizer. Fish were sampled every month for weight and length measurements. Fish were also sampled for biochemical analysis. T-test was used to compare the means between treatments. Fish from pond 1 gained significantly higher (p<0.05) weight compared to fish in pond 2. The specific growth rate and food conversion ratio also showed significantly higher (p<0.05) values for fish in pond 1 (1.52 and 2.4) compared to fish in pond 2 (1.22 and 2.1). Crude protein and lipid composition of fish were found significantly higher (p<0.05) in p...
Heteroatom-doped carbons are attractive materials for efficient energy generation as these can ca... more Heteroatom-doped carbons are attractive materials for efficient energy generation as these can catalyse reactions in high performance energy devices.
A highly sensitive electrochemical sensor based on immobilization of a newly synthesized urea fun... more A highly sensitive electrochemical sensor based on immobilization of a newly synthesized urea functionality containing surfactant, 1-(2, 4-dinitrophenyl)-dodecanoylthiourea (DAN), possessing soil fertility enhancing characteristics, was developed for the detection of Hg(II) using cyclic, square wave and differential pulse voltammetry. Under suitable experimental conditions, calibration plot with a good linearity up to 2 mg/L was obtained with a detection limit of 0.64 mg/L and sensitivity of 0.164 mAL/mg in doubly distilled water at accumulation time of 360 sec using square wave voltammetry. The proposed method was also used for the determination of Hg (II) in drinking and tap water samples with very good recovery data and relative standard deviation of less than 3.5%. The designed sensor exhibited remarkable electro-catalytic effect by dramatically boosting the signal of the analyte as compared to the bare electrode. Computational studies of the interaction of DAN and mercury were also performed. The theoretical results were found in good agreement with the experimental findings.
A highly sensitive electrochemical sensor using a novel surfactant 1-cyclohexyl-3-dodecanoylthiou... more A highly sensitive electrochemical sensor using a novel surfactant 1-cyclohexyl-3-dodecanoylthiourea (CDT) as a recognition layer was developed for the detection of Cd 2+ and Hg 2+ using electrochemical impedance spectroscopy, chronocoulometry and a number of voltammetric techniques such as cyclic, square wave and differential pulse stripping voltammetry. For optimization, the effect of several experimental factors such as concentration of the surfactant, scan rate, pH, accumulation time, number of cycles and supporting electrolytes were investigated. The limits of detection quite lower than the danger level suggested by world health organization (WHO), Environmental protection agency (EPA) and European water quality (EWQ) suggested the suitability of our designed sensor for monitoring metal based water toxins. Theoretical studies carried out for the calculation of interaction energy of CDT with Hg 2+ and Cd 2+ supported the experimental findings. The validity of the proposed method for real water sample analysis was ensured from reasonable percentage recoveries and less than 4% RSD values. Moreover, the designed sensor demonstrated excellent discrimination ability for the target analytes in the presence of interfering agents.
In the present work we report the development of a novel electrochemical sensor associated with h... more In the present work we report the development of a novel electrochemical sensor associated with high sensitivity, selectivity, cost affordability and fast sensing ability. We used 1-phenyl-N-(pyridin-2-ylmethyl)ethanamine (PPE) as a recognition layer over the surface of glassy carbon electrode for the trace level detection of mercuric (Hg 2þ) and cadmium (Cd 2þ) ions. The effects of pH, temperature, concentration of the modifier, accumulation time, deposition potential and supporting electrolytes were examined to optimize conditions for achieving the best sensing response of the analytes. The designed sensors demonstrated good percentage recovery, remarkable electrocatalytic activity and excellent discrimination ability for the target analytes in the presence of interfering metal ions. The wide linearity range and quite lower detection limits of 0.1 nM and 0.8 nM for Hg þ2 and Cd þ2 ions suggested the promising candidature of the designed sensor for monitoring heavy metal ions in aqueous systems.
We report for the first time the electrochemical detection of Zn 2+ , Cd 2+ , Cu 2+ and Hg 2+ at ... more We report for the first time the electrochemical detection of Zn 2+ , Cd 2+ , Cu 2+ and Hg 2+ at the surface of modified glassy carbon electrodes with different amino acids. The designed sensors showed superior heavy metal ion (HMs) detection limits, which are at lower levels than the thresholds suggested by the World Health Organization. The influence of the concentration of the modifier, pH, accumulation time, deposition potential and supporting electrolytes were tested for achieving the best sensing response of the analytes. The sensors demonstrated remarkable electrocatalytic activity and excellent discrimination ability for the target analytes in the presence of 200-fold higher concentration of interfering agents. Glycine was found to have the best HMs chelation ability among all the eight natural amino acids tested experimentally in this work. Theoretical DFT-based computational calculations supported the experimental results of HM-amino acid interaction. Thus, this work not only reports sensors with enhanced detection capability for HMs but also provides useful insights toward future designing of water filters containing amino acids-based materials for metal sequestration.
The electrochemical reduction of carbon dioxide (CO2) on copper electrode derived from cupric oxi... more The electrochemical reduction of carbon dioxide (CO2) on copper electrode derived from cupric oxide (CuO), named oxide derived copper (ODCu), was studied thoroughly in the potential range of −1.0 V to −1.5 V versus RHE. The CuO nanoparticles were prepared by the hydrothermal method. The ODCu electrode was used for carbon dioxide reduction and the results revealed that this electrode is highly selective for C2+ products with enhanced current density at significantly less overpotential. This catalyst shifts the selectivity towards C2+ products with the highest Faradaic efficiency up to 58% at −0.95 V. In addition, C2 product formation at the lowest onset potential of −0.1 V is achieved with the proposed catalyst. X-ray diffraction and scanning electron microscopy revealed the reduction of CuO to Cu (111) nanoparticles during the CO2 RR. The intrinsic property of the synthesized catalyst and its surface reduction are suggested to induce sites or edges for facilitating the dimerization ...
A highly sensitive electrochemical sensor based on immobilization of a newly synthesized urea fun... more A highly sensitive electrochemical sensor based on immobilization of a newly synthesized urea functionality containing surfactant, 1-(2, 4-dinitrophenyl)-dodecanoylthiourea (DAN), possessing soil fertility enhancing characteristics, was developed for the detection of Hg(II) using cyclic, square wave and differential pulse voltammetry. Under suitable experimental conditions, calibration plot with a good linearity up to 2 µg/L was obtained with a detection limit of 0.64 µg/L and sensitivity of 0.164 µAL/µg in doubly distilled water at accumulation time of 360 sec using square wave voltammetry. The proposed method was also used for the determination of Hg (II) in drinking and tap water samples with very good recovery data and relative standard deviation of less than 3.5%. The designed sensor exhibited remarkable electrocatalytic effect by dramatically boosting the signal of the analyte as compared to the bare electrode. Computational studies of the interaction of DAN and mercury were also performed. The theoretical results were found in good agreement with the experimental findings.
Abstract A highly sensitive electrochemical sensor using a novel surfactant 1-cyclohexyl-3-dodeca... more Abstract A highly sensitive electrochemical sensor using a novel surfactant 1-cyclohexyl-3-dodecanoylthiourea (CDT) as a recognition layer was developed for the detection of Cd 2+ and Hg 2+ using electrochemical impedance spectroscopy, chronocoulometry and a number of voltammetric techniques such as cyclic, square wave and differential pulse stripping voltammetry. For optimization, the effect of several experimental factors such as concentration of the surfactant, scan rate, pH, accumulation time, number of cycles and supporting electrolytes were investigated. The limits of detection quite lower than the danger level suggested by world health organization (WHO), Environmental protection agency (EPA) and European water quality (EWQ) suggested the suitability of our designed sensor for monitoring metal based water toxins. Theoretical studies carried out for the calculation of interaction energy of CDT with Hg 2+ and Cd 2+ supported the experimental findings. The validity of the proposed method for real water sample analysis was ensured from reasonable percentage recoveries and less than 4% RSD values. Moreover, the designed sensor demonstrated excellent discrimination ability for the target analytes in the presence of interfering agents.
The study was conducted to evaluate the effect of artificial feed and adding organic manures to t... more The study was conducted to evaluate the effect of artificial feed and adding organic manures to the earthen ponds on the growth and body composition of genetically improved farmed tilapia (GIFT). A total of 160 fish were stocked in each of the two ponds for 90 days. Fish in both ponds were fed with supplementary feed containing 30% crude protein at 4% body weight. Pond 1 was fertilized using cow dung and poultry manure while pond 2, received no fertilizer. Fish were sampled every month for weight and length measurements. Fish were also sampled for biochemical analysis. T-test was used to compare the means between treatments. Fish from pond 1 gained significantly higher (p<0.05) weight compared to fish in pond 2. The specific growth rate and food conversion ratio also showed significantly higher (p<0.05) values for fish in pond 1 (1.52 and 2.4) compared to fish in pond 2 (1.22 and 2.1). Crude protein and lipid composition of fish were found significantly higher (p<0.05) in p...
Heteroatom-doped carbons are attractive materials for efficient energy generation as these can ca... more Heteroatom-doped carbons are attractive materials for efficient energy generation as these can catalyse reactions in high performance energy devices.
A highly sensitive electrochemical sensor based on immobilization of a newly synthesized urea fun... more A highly sensitive electrochemical sensor based on immobilization of a newly synthesized urea functionality containing surfactant, 1-(2, 4-dinitrophenyl)-dodecanoylthiourea (DAN), possessing soil fertility enhancing characteristics, was developed for the detection of Hg(II) using cyclic, square wave and differential pulse voltammetry. Under suitable experimental conditions, calibration plot with a good linearity up to 2 mg/L was obtained with a detection limit of 0.64 mg/L and sensitivity of 0.164 mAL/mg in doubly distilled water at accumulation time of 360 sec using square wave voltammetry. The proposed method was also used for the determination of Hg (II) in drinking and tap water samples with very good recovery data and relative standard deviation of less than 3.5%. The designed sensor exhibited remarkable electro-catalytic effect by dramatically boosting the signal of the analyte as compared to the bare electrode. Computational studies of the interaction of DAN and mercury were also performed. The theoretical results were found in good agreement with the experimental findings.
A highly sensitive electrochemical sensor using a novel surfactant 1-cyclohexyl-3-dodecanoylthiou... more A highly sensitive electrochemical sensor using a novel surfactant 1-cyclohexyl-3-dodecanoylthiourea (CDT) as a recognition layer was developed for the detection of Cd 2+ and Hg 2+ using electrochemical impedance spectroscopy, chronocoulometry and a number of voltammetric techniques such as cyclic, square wave and differential pulse stripping voltammetry. For optimization, the effect of several experimental factors such as concentration of the surfactant, scan rate, pH, accumulation time, number of cycles and supporting electrolytes were investigated. The limits of detection quite lower than the danger level suggested by world health organization (WHO), Environmental protection agency (EPA) and European water quality (EWQ) suggested the suitability of our designed sensor for monitoring metal based water toxins. Theoretical studies carried out for the calculation of interaction energy of CDT with Hg 2+ and Cd 2+ supported the experimental findings. The validity of the proposed method for real water sample analysis was ensured from reasonable percentage recoveries and less than 4% RSD values. Moreover, the designed sensor demonstrated excellent discrimination ability for the target analytes in the presence of interfering agents.
In the present work we report the development of a novel electrochemical sensor associated with h... more In the present work we report the development of a novel electrochemical sensor associated with high sensitivity, selectivity, cost affordability and fast sensing ability. We used 1-phenyl-N-(pyridin-2-ylmethyl)ethanamine (PPE) as a recognition layer over the surface of glassy carbon electrode for the trace level detection of mercuric (Hg 2þ) and cadmium (Cd 2þ) ions. The effects of pH, temperature, concentration of the modifier, accumulation time, deposition potential and supporting electrolytes were examined to optimize conditions for achieving the best sensing response of the analytes. The designed sensors demonstrated good percentage recovery, remarkable electrocatalytic activity and excellent discrimination ability for the target analytes in the presence of interfering metal ions. The wide linearity range and quite lower detection limits of 0.1 nM and 0.8 nM for Hg þ2 and Cd þ2 ions suggested the promising candidature of the designed sensor for monitoring heavy metal ions in aqueous systems.
We report for the first time the electrochemical detection of Zn 2+ , Cd 2+ , Cu 2+ and Hg 2+ at ... more We report for the first time the electrochemical detection of Zn 2+ , Cd 2+ , Cu 2+ and Hg 2+ at the surface of modified glassy carbon electrodes with different amino acids. The designed sensors showed superior heavy metal ion (HMs) detection limits, which are at lower levels than the thresholds suggested by the World Health Organization. The influence of the concentration of the modifier, pH, accumulation time, deposition potential and supporting electrolytes were tested for achieving the best sensing response of the analytes. The sensors demonstrated remarkable electrocatalytic activity and excellent discrimination ability for the target analytes in the presence of 200-fold higher concentration of interfering agents. Glycine was found to have the best HMs chelation ability among all the eight natural amino acids tested experimentally in this work. Theoretical DFT-based computational calculations supported the experimental results of HM-amino acid interaction. Thus, this work not only reports sensors with enhanced detection capability for HMs but also provides useful insights toward future designing of water filters containing amino acids-based materials for metal sequestration.
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