Reticulated Replica Ceramic Foams: Processing, Functionalization, and Characterization

Abstract

Reticulated ceramic foams are used in a wide range of applications such as filters, catalyst supports, lightweight materials, energy absorptions materials, or as scaffolds for tissue engineering as the most common ones. Based on gaseous foaming processes of polymers, a stochastic distribution of closed pores is obtained. By reticulation processing thin foam windows are removed between cells turning a closed cell into an open cell structure. These foams are used as template for porous ceramics manufacturing: With different processing approaches, for example, with dip coating of a ceramic slurry and a subsequent (multistep) thermal treatment ceramic reticulate foams are obtained. A variety of material properties strongly depend on the cell and strut size, as well on material composition. Functionalization of ceramic foam surfaces (outer surface functionalization), for example, with zeolites or nanosized aggregates lead to an increase of the specific surface area or provides catalytic or heat storage functionality. Filling of struts (inner surface functionalization) may lead to improved mechanical stability or may provide functionalities such as electric conductivity. The present work summarizes the processing steps from the template foam to the final cellular ceramic, functionalization strategies, and the most common characterization techniques.

Hierarchical‐Porous Ceramic Foams by a Combination of Replica and Freeze Technique

“…Thus, the sintered ceramic foams represent a replica of the initial template foam. It should be noted that the struts of the replica foams are hollow because of the burn‐out of the template structure …”

“…If the specific surface area may be increased, the spectrum of possible applications may be expanded. Due to increased specific surface area and enhanced radiative transport properties, new tasks in the field of catalyst support or in high temperature applications can be opened . To increase the effective surface area the foams can be coated with a high surface area washcoat .…”

Reticulated Open-Celled Zinc Oxide Ceramic Foams: Manufacturing, Microstructure, Mechanical, and Thermal Properties

“…is results in a macrocellular foam-like structure similar to that of the polymeric sponge used as template in this process. A variety of cellular ceramic materials has been produced by this technique, an overview can be found in references [3,4]. However, to our knowledge, no zinc oxide foams have been prepared by the sponge replication process yet.…”

Preparation and Characterization of a Low-Cost and Natural Material-Based Reticulated Porous Diatomite-Kaolin Composite

“…Among the various types of porous ceramics, reticulated porous ceramics have well-defined open pore structures, whose porosity is generally above 90%. Therefore, reticulated porous ceramics [2] are prepared using various types of ceramics that are laid in an extreme edge of the advantages of porous ceramics.…”