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Summary: In this study, the electrocatalytic activity of mono‐metallic Co/NPC, bi‐metallic MnCo/NPC, and ternary NiMnCo/NPC in alkaline media for the methanol oxidation process was examined (MOR). These materials were produced using a simple solution mixing method and characterized using FTIR, EDX, SEM, XPS, TGA, and XRD. In a three‐electrode arrangement, on glassy carbon electrodes, the investigation of methanol oxidation for electrochemical activity of catalysts was carried in 1 M NaOH and 3 M CH3OH. Electrochemical studies included cyclic voltammetry (CV), chronoamperometry (CA), and electron impedance spectroscopy (EIS). The ternary NiMnCo/NPC composite, which has a peak current density of 147.85 mA/cm2 at 0.8 potential and a scan rate of 50 mV/s among all the composites developed, is a promising catalyst for methanol electrocatalysis. [ABSTRACT FROM AUTHOR]

Summary: Graphitic carbon nitride is of interest for its intercalation, ion exchange, and redox properties as it exhibits high catalytic activity. Besides, its high nitrogen content and facile synthesis procedure may provide a good balance between activity and durability. We report novel g‐C3N4 based MOF as a novel electrocatalyst for methanol oxidation reaction (MOR). Two methods are involved in the catalytic synthesis, namely the hydrothermal method for the Cu/Ni MOF and its composites synthesis, and g‐C3N4 is obtained by pyrolysis of melamine. To explore the structural and morphological properties, all the catalysts were eventually characterized using XRD, FTIR, SEM, and EDX techniques, whereas cyclic voltammetry (CV) revealed the electrochemical response for the oxidation of methanol in 3 M methanol and 1 M NaOH on modified glassy carbon electrode (GCE). The electrochemical results illustrate that as the amount of g‐C3N4 increases current density for methanol oxidation reaction (MOR). The maximum current density is 103.42 mA/cm2 shown by Cu/Ni MOF@5 wt% g‐C3N4 at 0.9 V while the scan rate is 50 mV/s. Thus, graphitic carbon nitride addition in MOF composites enhanced its durability and high carbon monoxide (CO) tolerance makes active catalysts in alkaline electrolyte. [ABSTRACT FROM AUTHOR]

In this study, biomass derived activated carbon (AC) was utilized to enhance the electrochemical properties of copper benzene-1, 3, 5-tricarboxylate metal organic framework (Cu-BTC MOF). Dried leaves (Lantana) were activated with phosphoric acid (H3PO4) for preparation of AC. Cu-MOF was pyrolyzed with different ratios of AC (1:1) under a reduction atmosphere of mixture of argon and hydrogen gases (90:10) in a tube furnace. These freshly produced composite materials were examined by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and thermal gravimetric analysis. The synthesized catalysts were tested for its electro catalytic activity for oxidation reduction reaction (ORR) in three electrode system by cyclic voltammetry, Tafel polarization and electrochemical impedance spectroscopy. The electrochemical parameters calculated by film coated glassy carbon electrode exhibit impact of activated carbon on oxidation reduction reaction catalyzed by Cu-BTC MOF. The composite Cu@AC (1:1) reported the highest current density of 2.11 mA cm−2 at 0.9 V potential with a scan rate of 50 mV s−1 in 0.1 M KOH which is better than commercial grade Pt/C having highest current density of 1.37 mA cm−2 at 0.86 V potential. The electrochemical activity and intensified constancy is due to synergistic influence of MOF and AC-composite. [ABSTRACT FROM AUTHOR]

Abstract In this work the electrochemical oxidation of methanol is studied on NiO based MOFs and its composites with reduced graphene oxides. NiO-MOF and its composites were prepared through hydrothermal method. The as-prepared materials were characterized by SEM, EDX, XRD, FTIR and Raman IR for their morphological and structural properties. The activity of prepared catalyst for oxidation of methanol was tested via cyclic voltammetry (CV) in an alkaline media on glassy carbon electrode. The electrochemical performance shows the effect of rGO concentration on methanol oxidation. The electro oxidation catalyzed by NiO-MOF and NiO-MOF/rGO composites exhibits a magnificent peak current density of 275.85 mA/cm2 at 0.8 V potential with a scan rate 50 mV/s making them a potential candidate for electrocatalysis. [ABSTRACT FROM AUTHOR]

In this work a novel bimetallic nickel oxide/copper oxide metal–organic framework (NiO/CuO MOF) has been developed by using two linkers: Benzene Dicarboxylic acid (BDC) and Pyrazine. The composites of NiO/CuO MOF with different amounts of reduced graphene oxide (rGO) were synthesized through a hydrothermal method and subsequently characterized by multiple significant techniques like XRD, SEM, EDX, FTIR and Raman IR for an investigation of their structural and morphological properties. The prepared series of material was later employed for electrochemical oxidation of methanol, tested by cyclic voltammetry (CV) in basic medium on a modified glassy carbon electrode (GCE). The electrochemical response depicts that increasing concentration of rGO enhances the electrocatalytic activity of the catalyst for methanol oxidation reaction (MOR). The catalyzed oxidation reaction of methanol by NiO/CuO MOF and rGO-NiO/CuO MOF composites give a superlative current density of 437. 28 mA/cm2 at 0.9 V potential at 50 mV/s scan rate. This activity makes it a promising catalytic material for electrolysis of methanol in direct methanol fuel cell (DMFC). [ABSTRACT FROM AUTHOR]

In this study, electrochemical oxidation of methanol to formic acid using the economical and highly active catalytic Nickel Benzene tricarboxylic acid metal organic framework (Ni-BTC-MOF) and reduced graphene oxide (rGO) nanocomposites modified glassy carbon electrode GCE in alkaline media, which was examined via cyclic voltammetry technique. Nickel based MOF and rGO nanocomposites were prepared by solvothermal approach, followed by morphological and structural characterization of prepared samples through X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and energy dispersive X-ray (EDX) analysis. The electrochemical testing of synthesized materials represents the effect of the sequential increase in rGO concentration on electrocatalytic activity. The Ni-BTC/4 wt % rGO composite with a pronounced current density of 200.22 mA/cm2 at 0.69 V versus Hg/HgO electrode at 50 mV/s was found to be a potential candidate for methanol oxidation in Direct Methanol Fuel Cell (DMFC) applications. Product analysis was carried out through Gas Chromatography (GC) and Nuclear Magnetic Resonance (NMR) spectroscopy, which confirmed the formation of formic acid during the oxidation process, with approximately 62% yield. [ABSTRACT FROM AUTHOR]