Zeolitic Imidazolate Framework Nanoleaves (Zif-L) Enhancement Of Strength And Durability Of Portland Cement Composites

In this study, we discovered that the introduction of 0.5% (by weight of cement) zeolitic imidazolate framework nano-leaves (ZIF-L) into cement can modify the cement paste's hydration and microstructure, resulting in an increase in the early compressive strength of the cement composites and improved resistance to both water ingress and acid attack. ZIF-L induced an initial set retardation effect of 1-2 h, followed by an improved degree of hydration, an effect distinct from that previously reported for mainstream nanomaterials. Based on experimental and simulation results, the retarding effect and the improved degree of hydration caused by ZIF-L were attributed to the adsorption of Ca2+ onto ZIF-L, which delayed onset of Ca(OH)(2) supersaturation in the wet mix resulting in a corresponding increased solubility of silicates, respectively. (C) 2020 Elsevier Ltd. All rights reserved.