Electrochemical Characterization of Cement-Based Materials

Electrochemical characterisation harnesses the response of cementitious materials to electrical excitation in order to probe their microstructural and chemical evolution. Techniques such as alternating current impedance spectroscopy measure the impedance of fresh and hardened cement pastes across a range of frequencies, yielding insight into pore solution conductivity, pore connectivity and the formation of solid hydrates. Resistivity measurements in both two- and four-point configurations enable non-destructive monitoring of hydration kinetics, early-age setting and long-term durability under environmental attack, including carbonation and chloride ingress. By modelling the electrochemical cell with equivalent circuits, quantitative parameters can be extracted that correlate with compressive strength, reaction degree and transport properties. These methods support the optimisation of mix design, the assessment of supplementary cementitious materials and the prediction of service life in infrastructure applications worldwide.

Research from Nature Portfolio

Recent studies have refined electrochemical cell design to reduce parasitic effects arising from electrode and lead impedances. By employing four-point measurement configurations and optimising conductive media, the influence of contact impedance can be rendered negligible, enabling higher-fidelity impedance spectra. Novel procedures for correcting frequency-dependent artefacts allow direct correlation of impedance features to distinct stages of cement hydration, from ionic dissolution to solid network formation. These advances establish standardised protocols for accurate, reproducible alternating current impedance spectroscopy of cement pastes under varied curing humidity conditions.

Electrochemical Characterization of Cement-Based Materials publication trend

The graph below shows the total number of articles in electrochemical characterization of cement-based materials across all publications each year (not limited to Nature Index journals).

Technical terms

Electrochemical impedance spectroscopy (EIS): A technique that applies a small alternating current over a range of frequencies to measure the impedance response of cementitious materials, revealing information on pore structure and chemical reactions.

Alternating current impedance spectroscopy (ACIS): Synonymous with EIS; emphasises the use of alternating current to probe the electrical properties of fresh and hardened cement pastes.

Formation factor: The ratio of pore solution resistivity to bulk resistivity of a cement paste, serving as an index of pore connectivity and moisture transport pathways.

Pore solution resistivity: The electrical resistivity of the liquid phase within the pore network of cementitious materials, reflecting ionic concentration and mobility.

Four-point measurement: An electrical testing configuration that uses separate pairs of current-injecting and voltage-measuring electrodes to minimise the influence of electrode contact impedance on resistivity measurements.

References

1. Study on the Carbonation Behavior of Cement Mortar by Electrochemical Impedance Spectroscopy. Materials (2014).
2. Investigation of the hydration properties of cement with EDTA by alternative current impedance spectroscopy. Cement and Concrete Composites (2022).
3. Real-time monitoring the electrical properties of pastes to map the hydration induced microstructure change in cement-based materials. Cement and Concrete Composites (2022).
4. Investigation of the early-age microstructural development of hydrating cement pastes through electrical resistivity measurements. Case Studies in Construction Materials (2020).
5. Electrochemical cell design and impedance spectroscopy of cement hydration. Journal of Materials Science (2020).
6. Permeability and Equivalent Circuit Model of Ionically Conductive Mortar Using Electrochemical Workstation. Materials (2020).
7. Evaluation of electrode-sample contact impedance under different curing humidity conditions during measurement of AC impedance of cement-based materials. Scientific Reports (2020).