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The majority of methanol oxidation electrocatalysts are based on platinum‐group metals such as platinum, palladium, and ruthenium. However, their usage is restricted because of their high cost, scarcity, and carbon monoxide toxicity concerns. We devised a simple approach for preparing a nickel foam (NF) based electrode using in‐situ synthesis of metal organic framework, such as Co‐MOF/NF, Ni‐MOF/NF, Mo‐MOF/NF, NC‐MOF/NF, MC‐MOF/NF, NM‐MOF/NF, and NMC‐MOF/NF, as an efficient electrocatalyst for methanol oxidation to produce carbon dioxide and water. Catalysts were synthesized using a hydrothermal process. In methanol with alkaline electrolyte, the as‐prepared NMC‐MOF/NF catalysts had the highest current density response, such as 5641 mA/cm2, in contrast to other bimetallic and single metal‐based metal organic framework electrocatalysts supported on Ni foam. We also observed that the NMC‐MOF/NF could efficiently catalyze the oxidation of carbon monoxide while being relatively unaffected by it. After 20,000 seconds in methanol oxidation, NMC‐MOF/NF based electrode retained about 100 % of its initial activity. Following simple synthesis technique and the improved catalytic efficiency and stability of NMC‐MOF/NF, methanol can be used to generate energy‐efficient products such as hydrogen. [ABSTRACT FROM AUTHOR]

In this research, electrocatalytic activity of cobalt benzene tricarboxylic acid metal organic framework (Co BTC MOF) and its reduced graphene oxide based composites (rGO/Co BTC) were investigated in an alkaline media for the methanol oxidation reaction (MOR). Metal Organic frameworks (MOF) and their composites were solvothermally prepared and characterized via FTIR, EDX, SEM and XRD. Electrochemical studies were performed by cyclic voltammetry, electron impedance spectroscopy, chronoamperometry and cyclic stability. Among all the prepared composites, 1 wt % rGO/Co BTC MOF (1.07 mg cm−2) demonstrated a promising current density of 130 mA cm−2 at 1.59 V vs. RHE, a tafel slope of 83.6 mV dec−1 and resistance of 14.75 Ω in 1 M NaOH/ 2 M methanol solution showing much better performance than state‐of‐the‐art Pt based materials. [ABSTRACT FROM AUTHOR]

In present work the development of copper benzenetricarboxylic acid metal organic framework (Cu-BTC MOF) based electrocatalyst and the effect of graphene oxide on catalytic activity of metal organic framework were studied for methanol oxidation reaction. Cu-MOF was prepared by a facile hydrothermal method and graphene oxide flakes were synthesized via improved Hummer's method. Surface morphological studies of catalyst were analyzed through scanning electron microscopy technique, which revealed cubic structure of crystals, while the crystallinity and functional groups present were characterized through X-ray Diffraction and FTIR spectroscopy respectively. Electrochemical studies were conducted by using cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometry techniques. Among all series of catalyst, 5 wt% GO/Cu-MOF exhibit highest current density of 120 mA/cm2 at a scan rate value of 50 mV/s at a voltage of 0.9 V. [ABSTRACT FROM AUTHOR]

The absence of stable and highly active non-precious metal electrocatalysts as a substitute to precious metal i.e., Pt (state-of-the-art) for methanol oxidation reaction in the application of direct methanol fuel cell considerably impedes the commercialization of these energy devices. In this work the electrocatalytic investigation of Fe-In MOF and its g-C3N4-based composites (i.e., 5–8 wt% g-C3N4@ Fe-In MOF) for methanol oxidation is reported. All the catalysts were prepared via solvothermal method. XRD, SEM, EDX, and FTIR were used to characterize the Fe-In MOF and its 5–8wt% g-C3N4 composites. In comparison to other prepared g-C3N4 based Fe-In MOF composites, the 7wt% g-C3N4 @ Fe-In MOF catalyst showed much greater electrochemical activity (i.e., 95.54 mA/cm2) and stability of 72.45% in 1 M NaOH and 3 M CH3OH. Due to graphitic carbon nitride specified high catalytic activity, intercalation, ion exchange, and redox properties. Further, the availability of iron (Fe) and indium (In) may also show a significant role in enhancing the electrocatalytic performance of 7wt% g-C3N4 @ Fe-In MOF over Fe-In MOF. They could be viewed as stable and economical electrocatalysts due to their numerous advantageous characteristics in structure, content, and nitrogen doping level. [ABSTRACT FROM AUTHOR]

• Mo-MOF, MO/NPC and MO-MS/NPC were synthesized via solvothermal method at 200 °C and pyrolysis. • All prepared composites were characterized via SEM, TEM, FTIR, XRD and XPS. • Synthesized series is tested for methanol oxidation and for oxygen reduction reactions. • MO-MS/NPC demonstrate higher electrochemical activity such as exhibiting 354.2 mA/cm2 current density for MOR and −9.54 ma/cm2 for ORR with low overpotential value of 0.80 V. In this paper, an effective method for synthesizing three different catalysts Mo-MOF, MO/NPC, and MO-MS/NPC by solvothermal preparation and pyrolysis processes has been described. The structural and compositional characteristics of these catalysts have been thoroughly analyzed using SEM, XRD, XPS, FTIR, and TEM characterization techniques. It is noteworthy that MO-MS/NPC has proven to have remarkable electrocatalytic capabilities, exhibiting high current density i.e., 354.3 mA/cm2 and stability in methanol oxidation as well as superior electrocatalytic activity for oxygen reduction reactions Because of these qualities, MO-MS/NPC, MO/NPC, and Mo-MOF might be an attractive option as cathodic and anodic materials in direct methanol fuel cells (DMFCs). Their higher oxygen reduction abilities as cathode materials can boost the cathodic reaction's effectiveness and encourage the conversion of oxygen and protons into water, and also help methanol to oxidize into carbon dioxide at the anode, liberating electrons that can be used to produce electricity. [ABSTRACT FROM AUTHOR]

In this work the catalytic activity of cobalt based MOF and its composites with graphene oxide (GO) towards electrochemical oxidation of methanol is studied. Co-MOF-71 and its GO composites were prepared by hydrothermal method and characterized by X-ray diffraction, XPS, scanning electron microscopy and FTIR. XRD patterns revealed incorporation of GO without disturbing the crystal structure. The synthesized catalysts were tested for their electrocatalytic activity for methanol oxidation reaction (MOR) in alkaline medium. The electrochemical parameters measured with modified GCE represent the effect of graphene oxide on methanol oxidation reaction catalysed by Co-MOF-71. Co-MOF-71/GO composite showed excellent peak current density (29.1 mA/cm 2 ) at lower potential (0.1 V) and scan rate of 50 mV/s. The enhanced electrochemical activity and stability is attributed to the synergetic effect of the MOF and the GO substrate for methanol oxidation. [ABSTRACT FROM AUTHOR]

• Nanostructured composites Mn/Zn N C @30% rGO, Mn/Zn N C @20% rGO, Mn/Zn N C @10% rGO was synthesized. • Mn/Zn N C @30% rGO demonstrates good electrocatalytic ORR activity in alkaline aqueous electrolyte solutions. • Mn/Zn N C @30% rGO has the lowest Tafel slope overpotential for attaining superior current density. • Mn/Zn N C @30% rGO has been proven reliable for test as fuel cross-over in methanol. Future fuel cells and metal-air batteries will benefit greatly from revealing self-supported electrodes with efficient oxygen reduction reaction (ORR) activity and durability. However, noble metal catalysts are expensive and unstable, necessitating research into novel metal-organic framework (MOF)-based topologies that can catalyse oxygen reduction reactions (ORR). In this work, the synthesis of nitrogen-doped carbon (N C) is derived from zeolitic imidazolate frameworks (ZIFs) and a novel Mn-doped Zn N C@rGO is synthesized using a self-templated solvothermal method and their performance in an alkaline medium for oxygen reduction reaction (ORR) is studied. The nanostructured composite outperformed the commercial Pt/C catalyst in terms of both material resources and application efficacy. The Mn/Zn N C @30% rGO exhibit outstanding performance for ORR in KOH, with a more positive cathodic peak of 0.78 V vs RHE and an onset potential of 0.97 V vs RHE, which are characteristics that suggest the possibility of reducing ORR overpotentials. The improved electrochemical performance, small Tafel slopes and methanol tolerance are ascribed to the interdependent effect of the N -doped carbon (N C) and the Mn/Zn active sites. Novel architecture, tunable porosities, template directed growth and remarkable electrocatalytic performance of Mn-doped Zn N C@rGO make it a good aspirant for energy applications. [ABSTRACT FROM AUTHOR]