Attempts to design porous carbon monoliths using porous concrete as a template - Part II: Some aspects of the pore formation mechanism.

Abstract Porous concrete has been proven as a promising template to prepare porous carbon monoliths because it can easily be formed to any geometric shape. To optimize the pore size distribution the template-assisted route can be combined with steps of the classical carbon activation such as the carbonization in the presence of zinc chloride. For the rational designing of such routes, profound knowledge of the pore-formation process is necessary. This is however complicated because the pore formation is the result of a complex interplay of different sub-processes. Here, we present approaches to estimate the contributions of these sub-processes to the overall porosity in a quantitative way. For that, the role of the template, the gasification reactions as well as the activating agent has been elucidated by elaborate analysis of nitrogen adsorption data. Graphical abstract Image 1 Highlights • Carbon pores result from the complex interplay of different sub-processes. • First approaches are presented to describe that interplay quantitatively. • The template contributes only little to the porosity of the carbon replica. • Gasification and activating agent, respectively, contribute nearly equally to the pore formation. [ABSTRACT FROM AUTHOR]