Advancements in cleaner production of one-part geopolymers: A comprehensive review of mechanical properties, durability, and microstructure

The demand for sustainable and eco-friendly construction materials has led to the development of a new type of geopolymer known as “just add water” or one-part geopolymer. However, persisting challenges arise in the consumption of current precursors and solid activators, stemming from issues of availability, environmental repercussions, and also the imperative to address the adverse consequences of waste materials and byproducts accumulation that are appropriate for incorporation into one-part geopolymers (OPGs). As a result, researchers have extensively investigated eco-conscious alternatives for both precursors and solid activators within the context of OPGs), drawing from waste materials and byproducts. Despite progress, the absence of comprehensive reviews impede the precise evaluation and comparison of more environmentally friendly options. The present review paper summarizes the recent research on cleaner solid activators and precursors, with simultaneous emphasis on sustainability and their effects on the fresh state characteristics, mechanical properties, durability and microstructure of OPGs. Comparative studies, underlying relationships, and current trends have also been compiled to provide guidelines and recommendations for producing sustainable OPGs. The analysis revealed that the OPGs containing mine tailings, glass waste, and rice husk ash as the cleaner precursor sources and calcium carbide residue and NaOH-treated waste glass as the solid activators demonstrated the highest embodied carbon/28-day compressive strength (ECI), outperforming other materials. In addition, the mixture containing NaOH-treated waste glass showed the best results through the simultaneous examination of both price of raw materials and ECI.