Empa magnesium team presenting at LCCS 2025, Ascona.

Empa magnesium team at LCCS 2025 presenting low-carbon Mg-based cements

The Empa team—Barbara Lothenbach, Ellina Bernard, Zeyu Zhou, Vincent Hallet, and Alexander German (former PhD at Empa)—had the privilege of joining the "Shaping the fate of low-carbon cement science" conference in the inspiring setting of Monte Verità (Mountain of Truth), Ascona, Switzerland. Much like the reformers who once gathered here seeking new ways of living, we shared our vision for a sustainable alternative to conventional cement—magnesium-based binders.

🔬 Our contributions:

Barbara Lothenbach opened the discussion with an overview of magnesium carbonate binders, highlighting their potential and Empa’s latest research breakthroughs.

Ellina Bernard combined the experimental results on the stability of Mg-Fe(III)-layered double hydroxides (pyroaurite) with modeling showing their potential importance within Mg-based binders.

Zeyu Zhou showed how Al (and Si) originating from metakaolin affect the MgO-Nesquehonite binder during hydration, such as the identification of the various phases that form as a result of these elements.

Vincent Hallet reported on the impact of relative humidity on the mechanical properties, comparing the differences between MgO-hydromagnesite and MgO-nesquehonite binders.

Alexander German presented his PhD journey of finding a new hydrated-magnesium-carbonate phase, called hydrous carbonate-containing brucite (HCB), and the latest structural understanding of this phase.

It was energizing to see the interest in Mg cements growing with several other presenters also working on the topic. We’re excited to see this field expand—to deepen our understanding, overcome greater challenges, and ultimately transform cement into a carbon sink for a sustainable future.

A heartfelt thanks to the organizers for creating this perfect platform for knowledge sharing, and to all participants for fueling such dynamic discussions. Toward buildings that heal rather than harm our climate!

People from left to right: Alexander German, Zeyu Zhou, Florian Rafalski, Ellina Bernard, Barbara Lothenbach, Saskia Franke, Vincent Hallet, Riccardo Guida, Chirayu Kothari.

Writing: Vincent Hallet (Empa, Switzerland)

Photo: Thomas Matschei (RWTH Aachen University, Germany)

#LowCarbonCement #SustainableMaterials #MgBasedBinders #CO2Reduction #EmpaResearch #LCCS2025