New insights into strontium aluminate cement hydration via correlative NV magnetometry, relaxometry, and spectroscopy techniques

This paper presents a novel approach to investigating the early hydration stages of strontium aluminate-based cement (SrAl₂O₄), utilizing nitrogen-vacancy (NV) color centers in nanodiamonds as precise quantum nanosensors . To monitor the in-situ dynamics of physicochemical processes occurring in the cement paste, Optically Detected Magnetic Resonance (ODMR), fluorescence microscopy, and spin-lattice relaxation time (T₁) measurements were employed. The obtained results were correlated with data from complementary methods, such as Electrochemical Impedance Spectroscopy (EIS), microcalorimetry, Raman microscopy, and X-ray Diffraction (XRD). The studies demonstrated that ODMR spectral parameters (including contrast and frequency shift) and luminescence intensity are sensitive to changes in the local chemical environment, temperature, and structural strains accompanying cement grain dissolution and hydrate precipitation. It was shown that magnetometry based on NV centers constitutes an effective tool for tracking chemical reactions and the microstructural evolution of binding materials at the micro-scale, offering high spatial resolution and real-time monitoring capabilities.

https://doi.org/10.1016/j.measurement.2026.120536