Md Fazle Shabik - Academia.edu (original) (raw)
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Papers by Md Fazle Shabik
Journal of Electroanalytical Chemistry, Sep 1, 2021
Abstract Electrocatalytic ammonia oxidation reaction (AOR) was executed on the copper oxide layer... more Abstract Electrocatalytic ammonia oxidation reaction (AOR) was executed on the copper oxide layer, electrochemically deposited on a glassy carbon electrode (GCE) surface. The XPS analysis revealed that the oxide film contains 80% Cu(I) and 20% Cu(II) species. The EIS analysis suggests that the resultant surface can catalyze ammonia oxidation reactions efficiently. The as prepared GCE-Cu2O.CuO favored the neutral medium for executing AOR with a degradation rate of 3.76 × 10−4 mol min−1 cm−2. Kinetic investigation shows that ammonia oxidation involves a three electron transfer first-order reaction. Tafel analysis of current–potential polarization curves indicates that species such as NH3 or NHads and NH2ads intermediates do not influence the reaction rate, which made the electrode unique for carrying out AOR. The formal potential value of AOR was evaluated to be ~0.7 V vs Ag/AgCl (sat.KCl) having standard rate constant (k°) of 5.52 × 10−6 cm/s.
Chemistry-an Asian Journal, Nov 16, 2020
The electrochemical behaviors of thiourea (TU) oxidation have been studied at Palladium (Pd) elec... more The electrochemical behaviors of thiourea (TU) oxidation have been studied at Palladium (Pd) electrode in the acidic medium by recording cyclic voltammograms (CVs). The influence of pH was investigated in the pH range of 1.0 to 9.0. Facilitated adsorption of TU on electrode surface results in enhanced catalytic response in acidic medium and maximum electro‐catalytic response was found at pH∼3.0. Chronoamperometric (CA) experiment determined this oxidation as 1e‐ transfer process and the variation of TU concentration reveals a 1st order kinetics. In the CV responses, the large value of peak separation (▵Ep >380 mV) calculated by the variation of scan rate indicates that oxidation of TU is an irreversible process. With the aid of convolution potential sweep voltammetry (CPSV), the standard rate constant (k°) for the reaction was found to be 7.1×10−4cm/s and the formal potential constant (E°′ ) was evaluated to be ∼0.37 V vs Ag/AgCl (sat. KCl). The value of transfer coefficient (α) was found to vary from 0.74 to 0.40 with applied potential (E). From the potential dependent variation of transfer coefficient (α) and activation energy (▵G≠), it was concluded that the overall electrochemical oxidation of TU follows a stepwise mechanism at lower potential (<0.40) V and a concerted one at relatively higher potential (>0.40) V. The FTIR analysis of the product after oxidation of TU molecules confirmed the appearance of a new sharp band near 530 cm−1 due to the formation of S−S bonds suggesting formation of formamidine disulfide (FD) ions.
Journal of Electroanalytical Chemistry, Apr 1, 2019
In the present paper, nitrite oxidation reaction has been performed using a pristine GC and Pd mo... more In the present paper, nitrite oxidation reaction has been performed using a pristine GC and Pd modified glassy carbon (GC) electrode to investigate catalysis and kinetics of nitrite (NO 2 −) oxidation reactions. The performance of GC electrode increased towards the nitrite oxidation reaction when it achieved catalytic influence from Pd particles. The NOR over the Pd-GC electrode followed by two steps process where the charge transfer steps coupled with the chemical reaction. The nitrite ions involve a single electron transfer reaction NO 2 being the product, which later undergo through a dispropornation reaction yielding NO 2 − and NO 3 − as final products.
Journal of Electroanalytical Chemistry, Sep 1, 2021
Abstract Electrocatalytic ammonia oxidation reaction (AOR) was executed on the copper oxide layer... more Abstract Electrocatalytic ammonia oxidation reaction (AOR) was executed on the copper oxide layer, electrochemically deposited on a glassy carbon electrode (GCE) surface. The XPS analysis revealed that the oxide film contains 80% Cu(I) and 20% Cu(II) species. The EIS analysis suggests that the resultant surface can catalyze ammonia oxidation reactions efficiently. The as prepared GCE-Cu2O.CuO favored the neutral medium for executing AOR with a degradation rate of 3.76 × 10−4 mol min−1 cm−2. Kinetic investigation shows that ammonia oxidation involves a three electron transfer first-order reaction. Tafel analysis of current–potential polarization curves indicates that species such as NH3 or NHads and NH2ads intermediates do not influence the reaction rate, which made the electrode unique for carrying out AOR. The formal potential value of AOR was evaluated to be ~0.7 V vs Ag/AgCl (sat.KCl) having standard rate constant (k°) of 5.52 × 10−6 cm/s.
Chemistry-an Asian Journal, Nov 16, 2020
The electrochemical behaviors of thiourea (TU) oxidation have been studied at Palladium (Pd) elec... more The electrochemical behaviors of thiourea (TU) oxidation have been studied at Palladium (Pd) electrode in the acidic medium by recording cyclic voltammograms (CVs). The influence of pH was investigated in the pH range of 1.0 to 9.0. Facilitated adsorption of TU on electrode surface results in enhanced catalytic response in acidic medium and maximum electro‐catalytic response was found at pH∼3.0. Chronoamperometric (CA) experiment determined this oxidation as 1e‐ transfer process and the variation of TU concentration reveals a 1st order kinetics. In the CV responses, the large value of peak separation (▵Ep >380 mV) calculated by the variation of scan rate indicates that oxidation of TU is an irreversible process. With the aid of convolution potential sweep voltammetry (CPSV), the standard rate constant (k°) for the reaction was found to be 7.1×10−4cm/s and the formal potential constant (E°′ ) was evaluated to be ∼0.37 V vs Ag/AgCl (sat. KCl). The value of transfer coefficient (α) was found to vary from 0.74 to 0.40 with applied potential (E). From the potential dependent variation of transfer coefficient (α) and activation energy (▵G≠), it was concluded that the overall electrochemical oxidation of TU follows a stepwise mechanism at lower potential (<0.40) V and a concerted one at relatively higher potential (>0.40) V. The FTIR analysis of the product after oxidation of TU molecules confirmed the appearance of a new sharp band near 530 cm−1 due to the formation of S−S bonds suggesting formation of formamidine disulfide (FD) ions.
Journal of Electroanalytical Chemistry, Apr 1, 2019
In the present paper, nitrite oxidation reaction has been performed using a pristine GC and Pd mo... more In the present paper, nitrite oxidation reaction has been performed using a pristine GC and Pd modified glassy carbon (GC) electrode to investigate catalysis and kinetics of nitrite (NO 2 −) oxidation reactions. The performance of GC electrode increased towards the nitrite oxidation reaction when it achieved catalytic influence from Pd particles. The NOR over the Pd-GC electrode followed by two steps process where the charge transfer steps coupled with the chemical reaction. The nitrite ions involve a single electron transfer reaction NO 2 being the product, which later undergo through a dispropornation reaction yielding NO 2 − and NO 3 − as final products.