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Herein, we report the electrocatalytic properties of Ag-M/C (M=Cu, Zn, Fe, Cr, Mn) catalysts produced using solution combustion synthesis (SCS) method for methanol oxidation reaction (MOR). The morphological properties of the synthesized catalysts were studied using SEM, EDX, TEM, XRD and XPS techniques. The characterization results indicated that out of all catalysts, AgCu/C had the most porous surface, small and well distributed particles with high surface area making it a good choice for electrocatalytic experiments. The XPS results showed a shift in peak in the AgCu/C sample due to the charge transfer between Ag and Cu indicating a strong interaction between Ag and Cu. The electrochemical properties of the catalysts were studied at 1 M methanol concentration and 1 M KOH (electrolyte) concentration by performing Cyclic Voltammetry (CV) and Linear Sweep Voltammetry (LSV) experiments. It was observed that AgCu/C exhibited a greater electrocatalytic activity and was therefore, found to be a more viable catalyst for MOR. Following this, further concentration studies were conducted on AgCu/C for methanol concentrations of 0.5M, 1M, 1.5M, 2.5M to evaluate the rate dependency of the catalyst on MeOH concentration. The CV and LSV curves depicted a linear increase in current density proportional to the increase in methanol concentration, indicating power-law dependency. The catalyst also displayed long-term stability when chronoamperometry test was performed for 20 hours.

Lanthanum-based synthetic perovskites (LaMnxCo1-xO3 (0≤x≤1)) were synthesized using a solution combustion synthesis technique with variable ratios of Co and Mn to investigates the surface and electrocatalytic property (activity and stability of catalysts) for methanol oxidation reaction (MOR), oxygen reduction reaction (ORR), oxygen evolution reaction (OER) under alkaline medium (KOH). The structural and morphological characterizations of the synthesized catalyst were performed by XRD, FTIR, SEM, TEM and XPS techniques. The structural and chemical properties systematically changed by varying the Mn to Co ratio in the perovskite structure. To observe the completion of combustion and temperature characteristics during the synthesis process, which are known to impact structural qualities, the time temperature profile during the combustion process was monitored. SEM/EDX and XPS analysis confirmed the formation of targeted ratio of Mn and Co on the catalyst. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) results revealed that all perovskite samples with different Co:Mn ratios were active for ORR, OER and MOR. The LaMnxCo1-xO3 perovskite with x=0.4 showed the highest current density compared to other samples towards all the investigated electrocatalytic reactions (MOR, ORR and OER) under alkaline reaction conditions.

Herein, we report the synthesis of silver-based electrocatalysts (Ag/C, AgCo/C, and AgNi/C) using solution combustion method and their performance towards methanol oxidation reaction. Detailed structural and microscopic analysis confirmed the formation of graphitic carbon, synthesis of crystalline phases with high porosity in all the three electrocatalysts. X-ray photoelectron spectroscopic (XPS) analysis showed a high concentration of Ag 2 O (or Ag + ) on AgNi/C, whereas AgCo/C exhibited a high concentration AgO (or Ag 2+ ) on the surface. XPS analysis on C 1s confirmed the highest concentrations of the sp 2 hybridized

Herein, we report the electrocatalytic properties of Ag-M/C (M=Cu, Zn, Fe, Cr, Mn) catalysts produced using solution combustion synthesis (SCS) method for methanol oxidation reaction (MOR). The morphological properties of the synthesized catalysts were studied using SEM, EDX, TEM, XRD and XPS techniques. The characterization results indicated that out of all catalysts, AgCu/C had the most porous surface, small and well distributed particles with high surface area making it a good choice for electrocatalytic experiments. The XPS results showed a shift in peak in the AgCu/C sample due to the charge transfer between Ag and Cu indicating a strong interaction between Ag and Cu. The electrochemical properties of the catalysts were studied at 1 M methanol concentration and 1 M KOH (electrolyte) concentration by performing Cyclic Voltammetry (CV) and Linear Sweep Voltammetry (LSV) experiments. It was observed that AgCu/C exhibited a greater electrocatalytic activity and was therefore, found to be a more viable catalyst for MOR. Following this, further concentration studies were conducted on AgCu/C for methanol concentrations of 0.5M, 1M, 1.5M, 2.5M to evaluate the rate dependency of the catalyst on MeOH concentration. The CV and LSV curves depicted a linear increase in current density proportional to the increase in methanol concentration, indicating power-law dependency. The catalyst also displayed long-term stability when chronoamperometry test was performed for 20 hours.