Abstract

In this research, the ambient-cured one-part alkali-activated material (AAM) containing graphene nanoplatelets (GNPs), fly ash, slag and silica fume has been investigated after high-temperature exposure to 200 – 800oC. Their compressive strength, thermal properties, microstructure, pore structure were characterised through visual observation, isothermal calorimetry, TGA, XRD, SEM/EDS and X-ray mCT. The research findings indicated high strength characteristics of the developed AAM (~ 80 MPa) at ambient condition, which could further reach to approx. 100 MPa after being heated up to 400oC. GNPs provided nucleation effects for promoting geopolymerisation and crystallisation. As observed from X-ray CT, a high extent of severe cracks initiated from the core and propagated towards the surface. From SEM/EDS analysis, high Na/Al and Na/Si ratios or low Si/Al and Ca/Si ratios highly correlated to thermal stability. Overall, the research outcomes implied the promising use of the nano-engineered AAMs for thermal energy storage (TES) at 400 – 600oC.

Abstract

In this research, the ambient-cured one-part alkali-activated material (AAM) containing graphene nanoplatelets (GNPs), fly ash, slag and silica fume has been investigated after high-temperature exposure to 200 – 800oC. Their compressive strength, thermal properties, microstructure, pore structure were characterised through visual observation, isothermal calorimetry, TGA, XRD, SEM/EDS and X-ray mCT. The research findings indicated high strength characteristics of the developed AAM (~ 80 MPa) at ambient condition, which could further reach to approx. 100 MPa after being heated up to 400oC. GNPs provided nucleation effects for promoting geopolymerisation and crystallisation. As observed from X-ray CT, a high extent of severe cracks initiated from the core and propagated towards the surface. From SEM/EDS analysis, high Na/Al and Na/Si ratios or low Si/Al and Ca/Si ratios highly correlated to thermal stability. Overall, the research outcomes implied the promising use of the nano-engineered AAMs for thermal energy storage (TES) at 400 – 600oC.

Abstract

In this research, the ambient-cured one-part alkali-activated material (AAM) containing graphene nanoplatelets (GNPs), fly ash, slag and silica fume has been investigated after high-temperature exposure to 200 – 800oC. Their compressive strength, thermal properties, microstructure, pore structure were characterised through visual observation, isothermal calorimetry, TGA, XRD, SEM/EDS and X-ray mCT. The research findings indicated high strength characteristics of the developed AAM (~ 80 MPa) at ambient condition, which could further reach to approx. 100 MPa after being heated up to 400oC. GNPs provided nucleation effects for promoting geopolymerisation and crystallisation. As observed from X-ray CT, a high extent of severe cracks initiated from the core and propagated towards the surface. From SEM/EDS analysis, high Na/Al and Na/Si ratios or low Si/Al and Ca/Si ratios highly correlated to thermal stability. Overall, the research outcomes implied the promising use of the nano-engineered AAMs for thermal energy storage (TES) at 400 – 600oC.

Abstract

In this research, the ambient-cured one-part alkali-activated material (AAM) containing graphene nanoplatelets (GNPs), fly ash, slag and silica fume has been investigated after high-temperature exposure to 200 – 800oC. Their compressive strength, thermal properties, microstructure, pore structure were characterised through visual observation, isothermal calorimetry, TGA, XRD, SEM/EDS and X-ray mCT. The research findings indicated high strength characteristics of the developed AAM (~ 80 MPa) at ambient condition, which could further reach to approx. 100 MPa after being heated up to 400oC. GNPs provided nucleation effects for promoting geopolymerisation and crystallisation. As observed from X-ray CT, a high extent of severe cracks initiated from the core and propagated towards the surface. From SEM/EDS analysis, high Na/Al and Na/Si ratios or low Si/Al and Ca/Si ratios highly correlated to thermal stability. Overall, the research outcomes implied the promising use of the nano-engineered AAMs for thermal energy storage (TES) at 400 – 600oC.