hani sayahi - Academia.edu (original) (raw)

Papers by hani sayahi

Research paper thumbnail of Reusable and robust high sensitive non-enzymatic glucose sensor based on Ni(OH)2 nanoparticles

Analytica Chimica Acta, Aug 1, 2014

Nickel hydroxide nanoparticles were successfully electrodeposited on graphite electrode (Gr/NiONP... more Nickel hydroxide nanoparticles were successfully electrodeposited on graphite electrode (Gr/NiONP) and employed as a robust non-enzymatic glucose sensor. The results of cyclic voltammetry (CV) and chronoamperometry demonstrated that the Gr/NiONP electrode displayed high electrocatalytic activity toward glucose. The oxidation current is directly related to the glucose concentration from 1 μM to 15 mM. Besides, the glucose sensor displayed high sensitivity (2400 μA mM(-1) cm(-2)) with a detection limit of 0.53 μM (S/N=3) in basic solution. Moreover, the sensor showed excellent selectivity, reproducibility and stability properties. The relative standard deviation is 1.2% for 10 successive measurements in 16 μM glucose. Interestingly, the signal for glucose was maintained at 95% of its initial value even after 6 months of storage under ambient conditions. Gr/NiONP electrode has also been tested to detect glucose in human serum with satisfactory results.

Research paper thumbnail of Room-temperature defect-controlled fabrication of graphene via sustainable electrochemical exfoliation: An ultra-performance supercapacitor

Journal of energy storage, Sep 1, 2023

Research paper thumbnail of ZnCl<sub>2</sub>/Urea Eutectic Solvent as Stable Carbonylation Source for Benign Synthesis of 2–Benzimidazolones and 2–Imidazolones: An Effective Strategy for Preventing NH<sub>3</sub> Gas Evolution

ChemistrySelect, Oct 1, 2019

The synthesis of 2‐benzimidazolone and 2‐imidazolone derivatives from urea as an inexpensive wide... more The synthesis of 2‐benzimidazolone and 2‐imidazolone derivatives from urea as an inexpensive widely available carbonyl source is usually performed in high boiling organic solvents accompanied by ammonia evolution, due to urea decomposition. In this paper, a sustainable method has been introduced for the synthesis of these N,N‐heterocycles by employing zinc chloride:urea (1 : 3.5) type IV eutectic mixture under mild reaction conditions. No urea was used directly in the reaction owing to the fact that the eutectic mixture (containing urea itself) suffice to provide the carbonylation source. This new concept allowed the smooth conversion of a range of arene‐1,2‐diamines and benzoins to the corresponding N,N‐heterocycle in efficient yields. The remarkable advantage of this green protocol over other conventional heating procedures is that all reactions are conducted under open‐vessel conditions due to the absorption of the evolved ammonia by the eutectic mixture during the reaction process. (© WILEY‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2007)

Research paper thumbnail of Enhanced Efficiency of Dye-sensitized Solar Cells Based on Bulk Synthesized TiO<sub>2</sub>Nanorods Annealed at Different Temperatures

Journal of The Chinese Chemical Society, Sep 1, 2015

Nanocrystalline SnO 2-based dye-sensitized photoelectrochemical solar cells have very low open-ci... more Nanocrystalline SnO 2-based dye-sensitized photoelectrochemical solar cells have very low open-circuit voltages of 325-375 mV and efficiencies of ∼ 1%. However, on coating the SnO 2 crystallites with a thin film of MgO, the voltage and efficiency are increased to 650-700 mV and ∼ 6.5%, respectively. Evidence is presented to show that the photoexcited dye on the outer MgO shell could tunnel electrons to SnO 2 and that the low probability of reverse tunneling suppresses recombinations, thus increasing the efficiency. An explanation is also given as to understand why dye-sensitized TiO 2 cells are more efficient than those made from SnO 2 alone.

Research paper thumbnail of L-トリプトファン触媒Paal-Knorrピロール環状縮合:効率的でクリーンなリサイクル可能有機触媒

Research on Chemical Intermediates, 2016

Research paper thumbnail of Genetic algorithm-assisted artificial neural network modelling for remediation and recovery of Pb (II) and Cr(VI) by manganese and cobalt spinel ferrite super nanoadsorbent

Research paper thumbnail of Fast, selective and sensitive fluorescence detection of levofloxacin, Fe3+ and Cu2+ ions in 100% aqueous solution via their reciprocal recognition

The fluorescence detection of ions and pharmaceutical effluents by using organic chemosensors is ... more The fluorescence detection of ions and pharmaceutical effluents by using organic chemosensors is a valuable surrogate to the currently existing expensive analytical methods. In this regard, the design of multi-functional chemosensors to recognize desirable guests is of utmost importance. In this study, we first show that levofloxacin (LVO) is able to use as a fluorescent chemosensor for the detection of biologically important Cu2+ (turn-off) and Fe3+ (turn-on) ions via independent signal outputs in 100% aqueous buffer solutions. Next, using the reciprocal recognition of LVO and Fe3+ provides a unique emission pattern for the detection of LVO. This approach exhibited a high specificity to LVO among various pharmaceutical samples, namely acetaminophen (AC), azithromycin (AZ), gemifloxacin (GEM) and ciprofloxacin (CIP) and also showed great anti-interference property in urine. The attractive features of this sensing system are availability, easy-to-use, high sensitivity (limit of detec...

Research paper thumbnail of L-トリプトファン触媒Paal-Knorrピロール環状縮合:効率的でクリーンなリサイクル可能有機触媒 | 文献情報 | J-GLOBAL 科学技術総合リンクセンター

Research on Chemical Intermediates, 2016

Research paper thumbnail of Ascorbic acid as a multifunctional hydrogen bonding catalyst for Paal–Knorr synthesis of N-substituted mono- and bis-pyrroles: experimental and theoretical aspects

Research on Chemical Intermediates

Research paper thumbnail of Asphaltene Aggregation Under the Influence of Structural Features and Interaction Energies: Combination of Quantum Mechanical and Molecular Dynamics Approaches

Research paper thumbnail of Genetic Algorithm-Assisted Artificial Neural Network for the Estimation of Drilling Parameters of Magnesium AZ91 in Vertical Milling Machine

Surface Review and Letters, 2020

The selection of appropriate drilling parameters is essential for improving productivity and part... more The selection of appropriate drilling parameters is essential for improving productivity and part quality, therefore, this work mainly concentrates on the investigation of drilling time, burr height, burr thickness, roundness and surface roughness. The drilling experiments were carried out on Magnesium (Mg) AZ91 with High Speed Steel (HSS) tool using the Vertical Milling Machine (VMM). The parameters reckoned are spindle speed and feed rate. Artificial Neural Network (ANN) was concerned with the building of the model that will be used to forecast the responses following the consideration of Response Surface Methodology (RSM). Conventional method of modeling (RSM) yields poorer results which redirected the study with ANN. The Genetic Algorithm (GA)-based ANN has been reckoned for developing the model. With two nodes in the parameter layer and seven nodes in the response layer, six different networks were constructed using variety of nodes in the hidden layers which are 2–6–7, 2–7–7, ...

Research paper thumbnail of Synthesis of MnO2/Graphite Nanocomposites using Sonochemistry Method for Electrochemical Supercapacitors

Research paper thumbnail of Preparation of MnO2/Carbon Black Nanocomposites Using Sonochemistry Method for Electrochemical Supercapacitors

Research paper thumbnail of Electrophoretic Deposition (Epd), Dye-Sensitized Solar Cells (DSSCS), Differential Scanning Calorimetry (DSC), TIO2 Nanoparticle

Research paper thumbnail of Superadsorbent Fe3O4-coated carbon black nanocomposite for separation of light rare earth elements from aqueous solution: GMDH-based Neural Network and sensitivity analysis

Journal of Hazardous Materials

Research paper thumbnail of TiO2 nanorods integrated with titania nanoparticles: Large specific surface area 1D nanostructures for improved efficiency of dye-sensitized solar cells (DSSCs)

Research paper thumbnail of Effect of large TiO2 Nanoparticles as Light Scatter in Matrix of Small Nanoparticles to Improve the Efficiency in Dye-Sensitized Solar Cell

sid.ir

In this study, we investigated the effect of using large TiO 2 nanoparticles in the matrix of sma... more In this study, we investigated the effect of using large TiO 2 nanoparticles in the matrix of small nanoparticles to improve the performance of dye-sensitized solar cells (DSSCs), as light scatter to increase the light harvesting. The mixed powder was deposited by electrophoretic deposition (EPD) on FTO (F-SnO 2 coated glass). It is shown that adding small quantity of larger nanoparticles can enhance the performance of DSSCs. This paper also studies the deferential scanning calorimetry (DSC) of mixed powders to detect the phase transitions, due to the change of weight percentage between large and small nanoparticles.

Research paper thumbnail of Enhanced efficiency of the dye-sensitized solar cells by excimer laser irradiated carbon nanotube network counter electrode

Applied Physics Letters, 2014

Research paper thumbnail of Investigating the effects of post-heat treatment temperatures on the structure of prepared nanorod by hydrothermal method

Journal of Nanostructures, 2011

In this study, the TiO2 nanorods were synthesized from P25 TiO2 nanoparticles by hydrothermal met... more In this study, the TiO2 nanorods were synthesized from P25 TiO2 nanoparticles by hydrothermal method in 10 M NaOH solution. The effects of annealing temperatures on produced nanorods were investigated by scanning electron microscopy (SEM) X-ray diffraction (XRD) and photoluminescence (PL) spectroscopy. Diameter growth and changes of surface oxygen defects of synthesized nanorods are studied with increasing annealing temperatures.

Research paper thumbnail of A highly sensitive “ON–OFF” optical sensor for the selective detection of cyanide ions in 100% aqueous solutions based on hydrogen bonding and water assisted aggregation induced emission

Chemical Communications

Nanoparticles N,N′-(pyridine-2,6-diyl)bis(2-(2,4-dichlorophenoxy)acetamide) (1) exhibited an “on–... more Nanoparticles N,N′-(pyridine-2,6-diyl)bis(2-(2,4-dichlorophenoxy)acetamide) (1) exhibited an “on–off” emission response toward cyanide (CN−) ions in 100% aqueous solutions based on AIE features.

Research paper thumbnail of Reusable and robust high sensitive non-enzymatic glucose sensor based on Ni(OH)2 nanoparticles

Analytica Chimica Acta, Aug 1, 2014

Nickel hydroxide nanoparticles were successfully electrodeposited on graphite electrode (Gr/NiONP... more Nickel hydroxide nanoparticles were successfully electrodeposited on graphite electrode (Gr/NiONP) and employed as a robust non-enzymatic glucose sensor. The results of cyclic voltammetry (CV) and chronoamperometry demonstrated that the Gr/NiONP electrode displayed high electrocatalytic activity toward glucose. The oxidation current is directly related to the glucose concentration from 1 μM to 15 mM. Besides, the glucose sensor displayed high sensitivity (2400 μA mM(-1) cm(-2)) with a detection limit of 0.53 μM (S/N=3) in basic solution. Moreover, the sensor showed excellent selectivity, reproducibility and stability properties. The relative standard deviation is 1.2% for 10 successive measurements in 16 μM glucose. Interestingly, the signal for glucose was maintained at 95% of its initial value even after 6 months of storage under ambient conditions. Gr/NiONP electrode has also been tested to detect glucose in human serum with satisfactory results.

Research paper thumbnail of Room-temperature defect-controlled fabrication of graphene via sustainable electrochemical exfoliation: An ultra-performance supercapacitor

Journal of energy storage, Sep 1, 2023

Research paper thumbnail of ZnCl<sub>2</sub>/Urea Eutectic Solvent as Stable Carbonylation Source for Benign Synthesis of 2–Benzimidazolones and 2–Imidazolones: An Effective Strategy for Preventing NH<sub>3</sub> Gas Evolution

ChemistrySelect, Oct 1, 2019

The synthesis of 2‐benzimidazolone and 2‐imidazolone derivatives from urea as an inexpensive wide... more The synthesis of 2‐benzimidazolone and 2‐imidazolone derivatives from urea as an inexpensive widely available carbonyl source is usually performed in high boiling organic solvents accompanied by ammonia evolution, due to urea decomposition. In this paper, a sustainable method has been introduced for the synthesis of these N,N‐heterocycles by employing zinc chloride:urea (1 : 3.5) type IV eutectic mixture under mild reaction conditions. No urea was used directly in the reaction owing to the fact that the eutectic mixture (containing urea itself) suffice to provide the carbonylation source. This new concept allowed the smooth conversion of a range of arene‐1,2‐diamines and benzoins to the corresponding N,N‐heterocycle in efficient yields. The remarkable advantage of this green protocol over other conventional heating procedures is that all reactions are conducted under open‐vessel conditions due to the absorption of the evolved ammonia by the eutectic mixture during the reaction process. (© WILEY‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2007)

Research paper thumbnail of Enhanced Efficiency of Dye-sensitized Solar Cells Based on Bulk Synthesized TiO<sub>2</sub>Nanorods Annealed at Different Temperatures

Journal of The Chinese Chemical Society, Sep 1, 2015

Nanocrystalline SnO 2-based dye-sensitized photoelectrochemical solar cells have very low open-ci... more Nanocrystalline SnO 2-based dye-sensitized photoelectrochemical solar cells have very low open-circuit voltages of 325-375 mV and efficiencies of ∼ 1%. However, on coating the SnO 2 crystallites with a thin film of MgO, the voltage and efficiency are increased to 650-700 mV and ∼ 6.5%, respectively. Evidence is presented to show that the photoexcited dye on the outer MgO shell could tunnel electrons to SnO 2 and that the low probability of reverse tunneling suppresses recombinations, thus increasing the efficiency. An explanation is also given as to understand why dye-sensitized TiO 2 cells are more efficient than those made from SnO 2 alone.

Research paper thumbnail of L-トリプトファン触媒Paal-Knorrピロール環状縮合:効率的でクリーンなリサイクル可能有機触媒

Research on Chemical Intermediates, 2016

Research paper thumbnail of Genetic algorithm-assisted artificial neural network modelling for remediation and recovery of Pb (II) and Cr(VI) by manganese and cobalt spinel ferrite super nanoadsorbent

Research paper thumbnail of Fast, selective and sensitive fluorescence detection of levofloxacin, Fe3+ and Cu2+ ions in 100% aqueous solution via their reciprocal recognition

The fluorescence detection of ions and pharmaceutical effluents by using organic chemosensors is ... more The fluorescence detection of ions and pharmaceutical effluents by using organic chemosensors is a valuable surrogate to the currently existing expensive analytical methods. In this regard, the design of multi-functional chemosensors to recognize desirable guests is of utmost importance. In this study, we first show that levofloxacin (LVO) is able to use as a fluorescent chemosensor for the detection of biologically important Cu2+ (turn-off) and Fe3+ (turn-on) ions via independent signal outputs in 100% aqueous buffer solutions. Next, using the reciprocal recognition of LVO and Fe3+ provides a unique emission pattern for the detection of LVO. This approach exhibited a high specificity to LVO among various pharmaceutical samples, namely acetaminophen (AC), azithromycin (AZ), gemifloxacin (GEM) and ciprofloxacin (CIP) and also showed great anti-interference property in urine. The attractive features of this sensing system are availability, easy-to-use, high sensitivity (limit of detec...

Research paper thumbnail of L-トリプトファン触媒Paal-Knorrピロール環状縮合:効率的でクリーンなリサイクル可能有機触媒 | 文献情報 | J-GLOBAL 科学技術総合リンクセンター

Research on Chemical Intermediates, 2016

Research paper thumbnail of Ascorbic acid as a multifunctional hydrogen bonding catalyst for Paal–Knorr synthesis of N-substituted mono- and bis-pyrroles: experimental and theoretical aspects

Research on Chemical Intermediates

Research paper thumbnail of Asphaltene Aggregation Under the Influence of Structural Features and Interaction Energies: Combination of Quantum Mechanical and Molecular Dynamics Approaches

Research paper thumbnail of Genetic Algorithm-Assisted Artificial Neural Network for the Estimation of Drilling Parameters of Magnesium AZ91 in Vertical Milling Machine

Surface Review and Letters, 2020

The selection of appropriate drilling parameters is essential for improving productivity and part... more The selection of appropriate drilling parameters is essential for improving productivity and part quality, therefore, this work mainly concentrates on the investigation of drilling time, burr height, burr thickness, roundness and surface roughness. The drilling experiments were carried out on Magnesium (Mg) AZ91 with High Speed Steel (HSS) tool using the Vertical Milling Machine (VMM). The parameters reckoned are spindle speed and feed rate. Artificial Neural Network (ANN) was concerned with the building of the model that will be used to forecast the responses following the consideration of Response Surface Methodology (RSM). Conventional method of modeling (RSM) yields poorer results which redirected the study with ANN. The Genetic Algorithm (GA)-based ANN has been reckoned for developing the model. With two nodes in the parameter layer and seven nodes in the response layer, six different networks were constructed using variety of nodes in the hidden layers which are 2–6–7, 2–7–7, ...

Research paper thumbnail of Synthesis of MnO2/Graphite Nanocomposites using Sonochemistry Method for Electrochemical Supercapacitors

Research paper thumbnail of Preparation of MnO2/Carbon Black Nanocomposites Using Sonochemistry Method for Electrochemical Supercapacitors

Research paper thumbnail of Electrophoretic Deposition (Epd), Dye-Sensitized Solar Cells (DSSCS), Differential Scanning Calorimetry (DSC), TIO2 Nanoparticle

Research paper thumbnail of Superadsorbent Fe3O4-coated carbon black nanocomposite for separation of light rare earth elements from aqueous solution: GMDH-based Neural Network and sensitivity analysis

Journal of Hazardous Materials

Research paper thumbnail of TiO2 nanorods integrated with titania nanoparticles: Large specific surface area 1D nanostructures for improved efficiency of dye-sensitized solar cells (DSSCs)

Research paper thumbnail of Effect of large TiO2 Nanoparticles as Light Scatter in Matrix of Small Nanoparticles to Improve the Efficiency in Dye-Sensitized Solar Cell

sid.ir

In this study, we investigated the effect of using large TiO 2 nanoparticles in the matrix of sma... more In this study, we investigated the effect of using large TiO 2 nanoparticles in the matrix of small nanoparticles to improve the performance of dye-sensitized solar cells (DSSCs), as light scatter to increase the light harvesting. The mixed powder was deposited by electrophoretic deposition (EPD) on FTO (F-SnO 2 coated glass). It is shown that adding small quantity of larger nanoparticles can enhance the performance of DSSCs. This paper also studies the deferential scanning calorimetry (DSC) of mixed powders to detect the phase transitions, due to the change of weight percentage between large and small nanoparticles.

Research paper thumbnail of Enhanced efficiency of the dye-sensitized solar cells by excimer laser irradiated carbon nanotube network counter electrode

Applied Physics Letters, 2014

Research paper thumbnail of Investigating the effects of post-heat treatment temperatures on the structure of prepared nanorod by hydrothermal method

Journal of Nanostructures, 2011

In this study, the TiO2 nanorods were synthesized from P25 TiO2 nanoparticles by hydrothermal met... more In this study, the TiO2 nanorods were synthesized from P25 TiO2 nanoparticles by hydrothermal method in 10 M NaOH solution. The effects of annealing temperatures on produced nanorods were investigated by scanning electron microscopy (SEM) X-ray diffraction (XRD) and photoluminescence (PL) spectroscopy. Diameter growth and changes of surface oxygen defects of synthesized nanorods are studied with increasing annealing temperatures.

Research paper thumbnail of A highly sensitive “ON–OFF” optical sensor for the selective detection of cyanide ions in 100% aqueous solutions based on hydrogen bonding and water assisted aggregation induced emission

Chemical Communications

Nanoparticles N,N′-(pyridine-2,6-diyl)bis(2-(2,4-dichlorophenoxy)acetamide) (1) exhibited an “on–... more Nanoparticles N,N′-(pyridine-2,6-diyl)bis(2-(2,4-dichlorophenoxy)acetamide) (1) exhibited an “on–off” emission response toward cyanide (CN−) ions in 100% aqueous solutions based on AIE features.