Fabrication of Alkaline Electrolyzer Using Ni@MWCNT as an Effective Electrocatalyst and Composite Anion Exchange Membrane

Abstract

Here, we report the synthesis of nickel nanoparticles thermally encapsulated in multiwalled carbon nanotubes (MWCNTs) and its utility in alkaline water splitting by combining with composite thermoset anion-exchange membrane. Ni@MWCNT displayed both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). It provided 10 mA cm –2 current density at an overpotential of 300 mV for OER and 254 mV for HER on a glassy carbon electrode, respectively. Base-catalyzed N-methly-4-piperidone-formaldehyde-based prepolymer was grafted on to poly(vinyl alcohol) and cross-linked via thermal annealing followed by quaternization using methyl iodide to obtain thermoset anion exchange membrane (NMPi). Composite NMPi membranes were synthesized using additives tetraethyl orthosilicate (TEOS) and zirconium oxychloride. The water splitting performance on the fabricated membrane electrode assembly was tested and compared with commercially available Neosepta membrane. The obtained faradic efficacy of the water splitting was 94.33% for ZrO 2 -NMPi membrane followed by 80.23%, 77.70%, and 65.10% for SiO 2 -NMPi, NMPi, and Neosepta membranes, respectively. The best membrane ZrO 2 -NMPi achieved maximum current density of ∼0.776 A cm –2 in 5 M KOH electrolyte at 80 °C and 2 V applied constant voltage. The excellent alkaline stability of MEA indicates its potential utility in hydrogen generation applications.

Influence of Multi-Walled Carbon Nanotube Modified Carbon Fiber Material Prepared by Electrophoretic Deposition on the Properties of Chlorobutyl Rubber/Natural Rubber Composite Materials

“…The storage modulus (G') of the composites increases and the loss factor (tanδ) decreases with the increase of frequency.The storage modulus of the composites with 5 phr CF and 5 phr MWCNTs is the highest, because CF and MWCNTs are rigid bodies, which increase the hardness of the composites. CF and MWCNTs are encapsulated by rubber matrix and increase the crosslinking degree of the composites, so the storage modulus increases [24] . The higher the storage modulus, the poorer the dispersion effect of CF and MWCNTs in the blend and the greater the possibility of agglomeration.…”

A Review of the Recent Advances in Composite Membranes for Hydrogen Generation Technologies

“…The water-splitting performance of this proposed composite membrane electrode assembly was compared with commercially available Neosepta membranes. 110 Studies in this field show that composite membranes with high performance, long life, and cost-effective production will continue to be studied without losing their importance in the future to investigate the use of green hydrogen production.…”

“…As stated in the review articles that summarize many successful studies on this subject, each membrane system has its advantages and disadvantages. − The study based on composite membrane described a preparation method using grafting and cross-linking of base-catalyzed N -methly-4-piperidone-formaldehyde-based prepolymer on poly­(vinyl alcohol) using additives tetraethyl orthosilicate (TEOS) and zirconium oxychloride. The water-splitting performance of this proposed composite membrane electrode assembly was compared with commercially available Neosepta membranes . Studies in this field show that composite membranes with high performance, long life, and cost-effective production will continue to be studied without losing their importance in the future to investigate the use of green hydrogen production.…”

Alkaline Water Splitting Using Hafnium‐Based Stable and Efficient Bifunctional Electrocatalyst

“…For achieving À 10 mA/cm 2 as current density, HfNiSe 2 /rGO requires an overpotential of 162 mV which is better than the most non-noble electrocatalyst for HER (Figure 4b). [64][65][66][67][68][69][70] Less overpotential gives better electrocatalytic activity for HER.…”