Dual Matrix Influence on Ni(II) Rich Hybrid Catalyst for Electrochemical Methanol Oxidation Reaction

Abstract

The influence of two different surface matrices, that is, zeolite‐Y and multi‐walled carbon nanotubes (MWCNTs), on the electrocatalytic ability of Ni(OH)2 combined with MnO2 has been studied. The Ni and Mn loaded in different ratio exhibited different current density with respect to the change in the nature of support. The MnO2−Ni(OH)2 catalyst decorated like a fish in a net‐stock at the interface of the zeolite‐Y and the MWCNT with high Ni(II) content provided the highest current density of 3.8 Amg−1 and 3.6 Amg−1 with platinum and graphitic rod as counter electrode, respectively. The study revealed that both the concentration of the Ni(II) as well as the nature of the support influenced the electrochemical behaviour of MnO2−Ni(OH)2. The electrochemical surface area as well as the durability of the catalyst having two different supports showed higher values in comparison to those in single matrix. The plot of current density vs. square root of scan rate showed diffusion control methanol oxidation process. The results predicted that the MnO2−Ni(OH)2 catalyst containing both zeolite‐Y and MWCNT surface indicated that under the highly basic condition it can withstand for long period without significant loss in current density during the methanol oxidation reaction process.

Ni(OH)2-SnO2 at the Hybrid Interface of Zeolite-Y and rGO for Electrochemical Oxidation of Methanol and Ethanol

“…The synthesized materials . 34,47 Although the FTIR analysis did not provide significant information, certain useful evidence was obtained from Raman analysis. The Raman signals for SnO 2 were observed at 292.8 and 615 cm −1 for the A 1g and E g vibrational bands, respectively, Figure 1c (black).…”

“…Tin oxide (SnO 2 ) supported on a hybrid matrix of zeolite-Y/rGO was synthesized following a similar procedure reported from our group . In a typical process 0.1 M SnCl 2 ·2H 2 O solution (prepared by dissolving 1.13 g of SnCl 2 ·2H 2 O in 50 mL of deionized water) was stirred with 2g of zeolite-Y by maintaining a pH of 10–12.…”

“…Tin oxide (SnO 2 ) supported on a hybrid matrix of zeolite-Y/rGO was synthesized following a similar procedure reported from our group. 34 In a typical process 0.1 M SnCl 2 •2H 2 O solution (prepared by dissolving 1.13 g of SnCl 2 •2H 2 O in 50 mL of deionized water) was stirred with 2g of zeolite-Y by maintaining a pH of 10−12. On stirring for 48 h under refluxing conditions at 60 °C, the solid material as obtained through filtration was washed several times to remove the Cl − ions.…”

“…Our recent investigation on the synthesis of Ni­(OH) 2 in the presence of other metal oxides such as Rh, Co, and Mn have provided information that zeolite matrices of aluminosilicate or zeolitic-like metal oxide can protect the Ni­(OH) 2 from oxidation by retaining its activity. ,, Besides, protecting the zeolites has other certain advantages including large surface area and pore spaces. ,, Zeolite-Y can encapsulate or immobilize homogeneous catalysts and can also be used as an internal hard template for the control synthesis of bimetallic nanoparticles. , Therefore, with our continuous interest in finding out a suitable electrocatalyst for alcohol fuel cells with specific interest to Ni­(OH) 2 , herein, we demonstrated the impact of SnO 2 in improving the electrocatalytic ability of Ni­(OH) 2 in alcohol (methanol and ethanol) fuel cells. The reason behind considering SnO 2 is that it has been found to have various applications in photocatalytic reactions and as sensing materials. − Apart from that, Sn can shuttle its oxidation from Sn 4+ to Sn 2+ and thereby can help the MOR and EOR by providing two electrons (2e – ).…”

“…Our recent investigation on the synthesis of Ni(OH) 2 in the presence of other metal oxides such as Rh, Co, and Mn have provided information that zeolite matrices of aluminosilicate or zeolitic-like metal oxide can protect the Ni(OH) 2 from oxidation by retaining its activity. 27,33,34 Besides, protecting the zeolites has other certain advantages including large surface area and pore spaces. 27,28,34 Zeolite-Y can encapsulate or immobilize homogeneous catalysts and can also be used as an internal hard template for the control synthesis of bimetallic nanoparticles.…”