Performance, radiation shielding, and anti-fungal activity of alkali-activated slag individually modified with zinc oxide and zinc ferrite nano-particles

Abstract

In this paper, low-cost nano-zinc ferrite (NZF) was used to evaluate its efficacy, as compared with nano-zinc oxide (NZO), on the performance of the fresh and hardened alkali activated slag (AAS). An elongation in setting times and a reduction in early-ages’ compressive strengths were recorded in the case of AAS individually containing 0.5, 1, and 1.5 wt% NZO. A turning point was observed after 3 days of curing as AAS-NZO set represents compressive strengths higher than those of reference sample. The embedding NZF in alkali activated system has resulted in setting time shortening and mechanical properties improvement at both early and later ages. This means that the acceleration effect of nano-ferrite compensates the retardation impact of NZO on the activation of AAS-hydration. Regardless its promising properties, AAS-NZF composites demonstrate compressive strength, γ-ray radiation shielding, and anti-fungal activity higher than those recorded in the case of AAS-NZO one at all addition levels.