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This perspective article delves into the transformative potential of alkali‐activated materials, acid‐activated materials, and geopolymers in mitigating climate change and market challenges. To harness the benefits of these materials, a comprehensive strategy is proposed. This strategy aims to integrate these materials into existing construction regulations, facilitate certification, and promote market access. Emphasizing research and innovation, the article advocates for, increased funding to refine the chemistry and production of these materials, prioritizing low‐cost alternatives and local waste materials. Collaboration between academia and industry is encouraged to expedite technological advances and broaden applications. This article also underscores the need to develop economic and business models emphasizing the long‐term benefits of these materials, including lower life‐cycle costs and reduced environmental impact. Incentivizing adoption through financial mechanisms like tax credits and subsidies is suggested. The strategy also includes scaling up production technology, fostering industrial collaboration for commercial viability, and developing global supply chains. Educational programs for professionals and regulators are recommended to enhance awareness and adoption. Additionally, comprehensive life‐cycle assessments are proposed to demonstrate environmental benefits. The strategy culminates in expanding the applications of these materials beyond construction, fostering international collaboration for knowledge sharing, and thus positioning these materials as essential for sustainable construction and climate change mitigation. [ABSTRACT FROM AUTHOR]

The synthesis method used has an important effect on the development of the compressive strength of a material. This work aims to research the effect of synthesis temperature (30oC and 70oC), curing condition (dried and sealed curing) and alkaline solutions (Sc commercial alkaline solution and Sl laboratory alkaline solution) on the development of compressive strength. The microstructure of these geopolymers was characterized using thermal analysis as well as porosity and microscopic observations, and the results were discussed. The total porosity was found to play a negative role on the compressive strength. Synthesis at a lower temperature demonstrated a better compressive strength due to the lower porosity and smaller pore sizes. The Sl geopolymers showed a better compressive strength than the Sc geopolymers due to their lower porosity. It was also found that the reaction was hindered when the samples were cured under a dried curing condition.

Highlights: [•] Samples of highly porous geopolymer foam were successfully made. [•] The overall thermal conductivity of samples were measured. [•] Multi-scale analytical approach was used to determine thermal skeleton thermal conductivity. [•] Finite element modeling taking into account the microstructure characteristics was used. [•] Analytical, numerical and experimental results highlight reliable numerical values. [ABSTRACT FROM AUTHOR]

Abstract: The characterization of the behavior of inorganic foams in aqueous media is defined as a function of various parameters (initial pH value of the solution, alkaline element and aging of the foam). The final products and their microstructure depend on the alkaline cation in relation with the hydration shell. Durability tests revealed that the geopolymer foam network is based on three compounds: a dense geopolymer depending on the alkaline element, amorphous silica and M2Si2O5. For potassium foam, a fourth component was also evidenced: a zeolite that is partly responsible for the degradation of this foam. [Copyright &y& Elsevier]

Abstract: Porous K-geopolymers with mutli-scale porosity were synthetized, based on the production of molecular hydrogen due to the oxidation of free silicon associated with polycondensation reactions. The various drying steps at low temperatures influencing the foams morphology were evaluated in function of parameters like mass effect, mold dimensions and drying cycles. The results obtained evidenced the possibility to perform reproducible foams with a control of their porosity. These foams are in agreement with the environmental demand with their recycling properties and their low cost of production due to the cheap materials used and the low temperature of synthesis. Some other advantages like their fire resistance, acid/base resistance, their good mechanical properties and their good thermal conductivity is a good point for future applications. As an example a homogeneous foam with a pore size of 1.5mm at 50°C (9 days for an achieved drying but consolidated before) can be prepared. Moreover the porosity can be controlled with various temperature cycles decreasing the time of synthesis. From the cycles tested (70–55°C and 70–23°C), some homogeneous samples were obtained with pores sizes varying from 0.5 to 1.5mm. Then the work was extended to larger surfaces exchange, what evidences the importance of drying and mass effects upon the porosity as well as the mechanical properties of the mold used during synthesis. [Copyright &y& Elsevier]

The present work carried out the influence of curing cycles on the performance of laterite-based geopolymer composites. To do so, the end products were obtained by altering laterite with 15, 20, and 25 wt% of rice husk ash (RHA). Alkaline solution in a constant solid/liquid ratio of 0.35 was added together with fine and coarse aggregates (representing equal and double weight of laterite, respectively). The different obtained matrices were treated in the following three curing cycles before characterization: room temperature curing (RTC), oven curing at 80 °C (OTC) and controlled humidity steam curing at 80 °C (STC). The mechanical tests carried out at 28 days give the following maximum values for each curing mode: 16.40, 28.82 and 56.41 MPa for RTC, OTC, and STC modes respectively. This means that when the samples, submitted in a moisture-controlled environment, the end products are more stable, less porous and resistant. Regarding the physical properties, the results show that the maximum value of open porosity is 11.62% corresponding to a matrix that was cured at room temperature without rice husk ash added, while the minimum value of 7% corresponds to a matrix that was cured under controlled humidity and containing 20% rice husk ash. The optimum and minimum absorption values are 2.70 and 4.60% respectively for the OTC and RTC curing modes. As for bulk densities, the optimum value is 2.64 g cm−3 for the matrix having 15% rice husk ash and the minimum value is 2.33 g cm−3 for a matrix having 20% rice husk ash, for OTC and STC curing modes respectively. The appropriate curing type for laterite-based geopolymer is when the humidity is controlled. • Laterite, aggregates and rice husk ash were used to produce geopolymer composites. • Geopolymer composites were cured at Room curing temperature (RTC), Oven curing and Steam curing (STC). • Applying the steam curing (STC) under controlled humidity (>65%) optimized the geopolymerization reaction. • High mechanical (56.41 MPa) was achieved on sample containing 25 wt% of RHA. • This sample also exhibits compact and dense structure with few accessible voids. [ABSTRACT FROM AUTHOR]

The progressive addition of the reactive silica from rice husk ash (10–50 wt%) changes the phases evolution and the microstructure of the laterites based geopolymer composites. It was found that the presence of soluble silica enhanced the formation of Si–(A)-OH–Fe bonds and changed considerably the FTIR and XRD patterns of the products: polysialates, ferrosialates and ferrisilicates were present into the matrices. The solid/liquid ratio and the curing cycle influenced the pore network, the bulk density, the total pore areas, and the final microstructure. The relative low viscous paste that is maintained at ambient temperature for 1–2 h before curing at 90 °C gave better cohesion and low porosity resulting to the high concentration of strongest (Fe–O–Si) bonds compared to pastes cured directly after preparation or those with high viscosity. While polysialates and ferrosilicates are hindered in the case of quite treatment at 80 °C due to the rapid evaporation of water, polysialates, ferrosialates and polynuclear ferrisilicates complexes are formed at room temperature and polynuclear complexes can growth to more crystalline phases with the increase of the temperature. Ferrisilicates integrated the interlayers of the matrix improving the geopolymerization with significant modification of the microstructure. Those newly formed phases are promising components for the development of eco-friendly and sustainable high strength composites, porous matrices for filtration, heavy metal removal/immobilization, membranes for catalysis and template for new carbone replicate. • Polysialates and Ferrosialates reinforced with ferrisilicates for sustainable and low cost porous system. • Development of curing system for the production of iron-rich aluminosilicates based geopolymers. • Cleaner product of ferrisilicates based functionalizing matrices for catalytic and filtration processes. [ABSTRACT FROM AUTHOR]