**4. Conclusions**

In this study, the ways geopolymer composites are designed and developed were summarized. According to the state-of-the-art, the following conclusions can be drawn:


Geopolymers are a promising, eco-friendly alternative to ordinary Portland cement (OPC). The production of geopolymer binders is associated with lower carbon dioxide emissions compared to the production of Portland cement. [30]. Industrial solid waste and waste incineration bottom ash are commonly piled up, taking up valuable land resources and posing environmental risks. However, these wastes can be recycled and used as raw materials for geopolymer production, which presents significant potential. The possibility of using geopolymer materials as an alternative to OPC binder allows to reduce the consumption of cement, which production is associated with high CO2 emissions.

**Figure 2.** Geopolymerization process and geopolymers applications [16].

**Author Contributions:** Conceptualization, T.M.M.I., M.S. and K.M.; methodology, K.M. and T.M.M.I.; software, M.S. and K.M.; validation, K..M. and M.R.; formal analysis, T.M.M.I.; investigation T.M.M.I., K.M., M.R. and M.S.; data curation, T.M.M.I., K.M., and M.S.; writing—original draft preparation, K.M. and M.S.; writing—review and editing, T.M.M.I., M.S. and K.M.; visualization, K.M. and M.S.; supervision, K.M.; project administration, K.M.; funding acquisition, K.M. and M.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the Cracow University of Technology and the Polish National Agency for foreign students in the framework of the project NAWA Spinaker, POWR.03.03.00-00- PN16/18. This research was supported by the National Centre for Research and Development in Poland in the framework of the project SMART-G Smart geopolymers (ERA MIN2-3/SMARTG/1/2022).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** This research was part of the work provided by two interdisciplinary research groups at Building Materials Engineering, Faculty of Civil Engineering, Cracow University of Technology (31-155 Cracow, Poland) and Buildings and Public Works, School of Engineering, CESI (76800 Saint Etienne du Rouvray, France). The publication cost of this paper was paid by the Polish National Agency for Academic Exchange (NAWA), "MATBUD'2023—Developing international scientific cooperation in the field of building materials engineering", BPI/WTP/2021/1/00002, MATBUD'2023.

**Conflicts of Interest:** There are no conflict of interest stated by the authors.

#### **References**


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