Study on the mechanism of constructing structure defects on surface of activated carbon with carbon black to promote hydrogen production by thermal-decomposition of methane

Abstract

Hydrogen production from catalytic decomposition of methane is a promising method of hydrogen production that caters to low-carbon energy sources. The low cost and easy regeneration of carbon-based catalysts is more compatible with the concept of sustainability than metal catalysts. The key problem with catalytic decomposition using activated carbon is the rapid deactivation of the activated carbon due to structural changes caused by the production and accumulation of deposited carbon. Carbon black, on the other hand, exhibits slowly increasing catalytic performance in the catalytic decomposition of methane. Therefore, combining the properties of the two, it is proposed to disperse and load the nano conductive carbon black onto the surface of urea-modified activated carbon, so that the activated carbon can also have self-repairing ability at a later stage. It is shown that the combined application of carbon black loading and urea modification enhances the structural properties of the activated carbon by enriching the microporous structure of the activated carbon surface, increasing the disorder of its crystal structure, and altering the content and concentration of oxygen-containing functional groups on the surface. These microstructural changes combined to enhance the overall catalytic activity of the activated carbon, including its late deactivation time and catalytic performance after deactivation.