Non-linear Chemistry of Complex Systems

Chemical reactions are not only fundamental for the synthesis of new products but also for the internal and spontaneous spatio-temporal organization of chemo-physical systems. The objective of our research is to develop, through combined experimental and theoretical approaches, a deeper understanding of how chemical reactions and their coupling with physical processes, such as (cross-)diffusion, convection , dissolution and phase transition, can lead to autonomous self-organized structures and functional behaviors. These include chemical oscillations, chemical patterns, waves, synchronization, and collective phenomena that underlie biological complexity. This fundamental knowledge can be used to design innovative strategies for applied problems in environmental and materials sciences.

Our current main research activities include the study of:

Chemical communication among self-sustained micro-oscillators, using oscillatory reactions encapsulated in microcompartments

Spatio-temporal dynamics and patterns resulting from the interplay between chemical reactions and transport processes. This interaction can account for the emergence of chaotic behaviors (analogous to the irregular patterns observed in cardiac arrhythmias) and the spontaneous onset of pulsatory dynamics in simple bimolecular reactions

Chemohydrodynamic mechanisms are also investigated for their potential application to CO₂ geological sequestration and the remediation of groundwater contaminated by dense non-aqueous phase liquids (DNAPLs)

Oscillatory behavior in hydrogen release from borohydride hydrolysis, a promising route for on-demand hydrogen storage and generation;

Mechanically activated reactive granular materials, offering a green route to chemical synthesis. In this context, we aim to develop a theoretical framework to correlate the complex dynamics of milling bodies inside a mechanochemical reactor with the resulting physicochemical transformations.

Additional research lines include the adaptation of nonlinear kinetics and reaction–transport models to isomorphic population dynamics.

- Marcello A., Budroni, mabudroni@uniss.it ,  RTDb, CHIM/02, ORCID: 0000-0003-1410-1745;

- Mauro, Rustici, rustici@uniss.it,  Professore Associato, CHIM/02, ORCID: 0000-0002-7292-8700

1. G. Facchini*, M. A. Budroni*, G. Schuszter, Fabian Brau, and A. De Wit, Phys. Rev. Lett. 135, 018001 (2025);

2. N. Valletti*, M.A. Budroni*, P. Albanese, N. Marchettini, M. Sanchez-Dominguez, I. Lagzi, F. Rossi, Hydrodynamically-enhanced transfer of dense non-aqueous phase liquids into an aqueous reservoir, Water Research, 119608 (2023);

3. M.A. Budroni, K. Torbensen, S. Ristori, A. Abou-Hassan, F. Rossi, Membrane structure drives synchronization patterns in arrays of diffusively coupled self-oscillating droplets, J. Phys. Chem. Lett., 11, 2014 (2020);

4. M.A. Budroni, V. Upadhyay, L. Rongy, Making a simple chemical reaction A + B --> C oscillate by coupling to a hydrodynamic effect, Phys. Rev. Lett., 122, 244502 (2019);

5. M.A. Budroni, S. Garroni, G.R.C. Mulas, M. Rustici, Bursting dynamics in molecular hydrogen generation via sodium borohydride hydrolysis, J. Phys. Chem. C, 121, 4891 (2017).

• CHANCE (ChemoHydrodynAmic-driveNComplExity), Prof. Mauro Rustici, Fondazione di Sardegna, 2021, 20000 €
• CAPTURE (Chemo-biologicAlly-driven convection for oPTimizedmixing in mUltiphasepaRtiallymisciblE systems), Prof. Mauro Rustici, Fondazione di Sardegna, 2017, 47000 €
• CHYPI, Chemo-Hydrodynamic Patterns and Instabilities, European Space Agency, Prof. Marcello Budroni, 2023 (Unità UNISS). 

1. Chemohydrodynamic oscillations induced by photochemical reactions. Fundamental study and possible applications.

2. Experimental and numerical study of phyllotactic-like structures created by chemical fronts.

3. Experimental and numerical study on the evolution of chemical oscillations and waves in a granular medium (halloysite).

4. pH oscillators controlled by a density-driven instability.

5. Spatio-temporal chemical oscillations induced by cross-diffusion.

6. Chemohydrodynamic methods for the recovery of fluids polluted by organic solvents (TCE).

7. Chemohydrodynamic methods for CO2 sequestration. Experimental and numerical study.

8. Experimental study of spatio-temporal chemical pulsations induced by bimolecular processes.

9. Hydrodynamic instabilities triggered by mechanochemical processing.

10. Experimental and modeling study of self-propagating processes and complex dynamics in mechanochemical systems.

11. Characterization and control of the kinetics of hydrogen release from sodium borohydride hydrolysis conducted under flow conditions.

12. Self-propulsion and collective motion of acetylsalicylic acid and hexaethylenediamine crystals.

13. Influence of acoustic waves in the spatio-temporal organization of chemical patterns on granular substrates.