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Atomic-Level and Surface Structure of Calcium Silicate Hydrate Nanofoils.

ABSTRACT: Deciphering the calcium silicate hydrate (C-S-H) surface is crucial for unraveling the mechanisms of cement hydration and property development. Experimental observations of C-S-H in cement systems suggest a surface termination which is fundamentally different from the silicate-terminated surface assumed in many atomistic level studies. Here, a new multiparameter approach to describing the (001) basal C-S-H surface is developed, which considers how the surface termination affects the overall properties (Ca/Si ratio, mean chain length, relative concentration of silanol and hydroxide groups). Contrary to current beliefs, it is concluded that the (001) C-S-H surface is dominantly calcium terminated. Finally, an adsorption mechanism for calcium and hydroxide ions is proposed, which is in agreement with the surface charge densities observed in previous studies.

SUBMITTER: Casar Z

PROVIDER: S-EPMC10518866 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature

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Atomic-Level and Surface Structure of Calcium Silicate Hydrate Nanofoils.

Casar Ziga Z Mohamed Aslam Kunhi AK Bowen Paul P Scrivener Karen K

The journal of physical chemistry. C, Nanomaterials and interfaces 20230908 37

Deciphering the calcium silicate hydrate (C-S-H) surface is crucial for unraveling the mechanisms of cement hydration and property development. Experimental observations of C-S-H in cement systems suggest a surface termination which is fundamentally different from the silicate-terminated surface assumed in many atomistic level studies. Here, a new multiparameter approach to describing the (001) basal C-S-H surface is developed, which considers how the surface termination affects the overall prop ...[more]

PMID: 37752905

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