A review on the porous geopolymer preparation for structural and functional materials applications

Geopolymer (also called inorganic polymers) is a kind of amorphous gel material with a 3D structure consisting of SiO 4 and AlO 4 tetrahedra. It has drawn international attention due to its environmental friendliness and excellent performance. This review covers raw materials, preparation methods, and applications of porous geopolymer materials with micropore, mesopore, or macropore. The preparation methods can be divided into five categories: (i) self‐forming method, (ii) direct foaming method, (iii) adding filler method, (iv) particles stacking method, and (v) other methods. In this paper, different raw materials and applications were combined with the preparation methods, and some general conclusions of porous geopolymer were summarized. The applications of porous geopolymer materials in building materials, adsorbents, porous ceramics, membrane separation, catalyst, pH regulator, and other fields were introduced as well.