A critical review of magnesium silicate hydrate (M-S-H) phases for binder applications
Harisankar Sreenivasan, Ellina Bernard, Hellen S. Santos, Hoang Nguyen, Samira Moukannaa, Adeolu Adediran, John L. Provis, Päivö Kinnunen
Abstract
Hydrated magnesium silicate materials are promising binding materials for applications as alternative cementitious materials and may offer a lower carbon footprint than conventional binders if carbon-free feedstocks are used. The reaction of reactive MgO with silica sources yields magnesium silicate hydrate (M-S-H) phases. These M-S-H phases have layered silicate structure and are stable from pH 8 to 12; thus, M-S-H phases are of interest for applications requiring low-pH binders, such as radioactive waste management and encapsulation. Reactive Mg-cements have been extensively studied in the past 100 years, yet the literature does not offer a dedicated review of M-S-H materials. This review provides a critical analysis of the current knowledge on M-S-H-based binders, discussing the main variables involved in M-S-H synthesis, the structure and characterization of these phases, thermodynamic parameters, stability, as well as the mechanical properties and potential applications of the resulting binders.