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Pre-Activation as a Route for Tuning the Kinetics of Mechanochemical Transformations
Christian Heinekamp1,2, Tahlia M Palmer3, Dominik Al-Sabbagh1
1Federal Institute for Materials Research and Testing (BAM), Richard-Willstätter Str 11, Berlin, 12489, Germany.
Angewandte Chemie (International Ed. in English)
|November 24, 2025
Summary
Controlling reaction kinetics is key for chemical technology. Pre-activating reagents in mechanochemistry can increase reaction rates up to 10-fold, offering a new way to control chemical reactions.
Area of Science:
- Solid-state chemistry
- Mechanochemistry
- Crystallization
Background:
- Controlling reaction kinetics is crucial for applying chemical technologies.
- Mechanochemical reactions offer a solvent-free synthesis route.
- Understanding factors influencing reaction rates is essential for process optimization.
Purpose of the Study:
- To investigate the effect of reagent pre-activation on mechanochemical reaction rates.
- To explore the influence of pre-activation on the polymorphic outcomes of mechano-co-crystallization.
- To provide a framework for controlling and designing mechanochemical processes.
Main Methods:
- Time-resolved in situ powder X-ray diffraction (PXRD) was used to monitor reactions.
- Three model co-crystal systems were studied.
- Reagents were subjected to pre-activation before mechanochemical processing.
Main Results:
- Pre-activation of the most stable reagent resulted in up to a 10-fold increase in reaction rate.
- Pre-activating the less stable reagent showed negligible kinetic enhancement.
- The polymorphic outcome of mechano-co-crystallization was sensitive to reagent pre-activation.
Conclusions:
- Reagent pre-activation is a viable strategy to tune mechanochemical reaction kinetics.
- The history and origin of reagent powders significantly impact the reproducibility of mechanochemical processes.
- This study offers a new conceptual framework for designing and controlling mechanochemical reactions.
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