Research

Different systems. Fundamental questions.

Our work asks how molecular and interfacial interactions, phase equilibria, and transport processes control behavior across scales. Colloid and interface science, physical chemistry, and self-assembly provide shared foundations; distinct research directions need not share identical mechanisms.

Research theme 01

Phase Behavior & Separation Phenomena

We investigate mixing, demixing, selective partitioning and phase evolution in multicomponent systems. Studies of chemically induced liquid–liquid separation, re-entrant behavior and freezing-induced solute segregation provide ways to test how intermolecular interactions, thermodynamics and kinetics determine macroscopic outcomes. Separating water-miscible contaminants is one application of these fundamental questions.

Nonideal mixturesLiquid–liquid separationMesoscale organizationFreeze segregation

When phase separation changes chemical partitioning

Chemical additives and freezing can reorganize multicomponent liquids in different ways. These experimental images illustrate how new phases and interfaces influence segregation and partitioning, without implying that each system follows the same mechanism.

Green confocal image with dark dispersed domains in the rhamnolipid-mediated THF–water system — Confocal microscopy of THF–water separation induced by rhamnolipids, bacterial biosurfactants. Fluorescent contrast shows THF-rich regions in green and water-rich regions in black.

Optical micrograph of NaOH-induced sulfolane-rich droplets with sulfur-rich interfacial regions and fine dispersed droplets — NaOH-induced sulfolane–water separation produces dispersed droplets, including nested droplets, without conventional surfactants. Elemental sulfur, which is poorly soluble in water, accumulates at liquid interfaces and can dissolve in the separated sulfolane-rich phase. The sulfur did not cause the demixing.

Optical micrograph of a frozen dilute sulfolane–water mixture showing ice-associated heterogeneous regions and a 100 micrometre scale bar — Freeze-induced segregation in a sulfolane–water mixture. Ice formation redistributes solute into unfrozen regions; measurements of the first thawed liquid establish the extent of sulfolane enrichment.

Optical micrograph of lignin-containing sulfolane–water mixture showing droplets and interfaces, with original 10 micrometre scale bar — Lignin-mediated phase separation in sulfolane–water mixtures. Preferential interactions between lignin and sulfolane can reduce aqueous miscibility and generate sulfolane-rich liquid domains.

Research theme 02

Transport Phenomena in Complex & Heterogeneous Media

We study how molecules and colloidal species move through liquids, interfaces, and porous and fractured media. Diffusion, sorption, interfacial exchange and chemical heterogeneity can influence retention, release, and migration. Changes in groundwater composition—including those produced by phase separation or chemical transformation—connect transport to our phase-behavior research. Contaminant migration provides an important experimental and environmental context.

Diffusion & sorptionPorous and fractured mediaChemical heterogeneityRetention & release

Research theme 03

Functional Soft Materials & Mechanoelectric Responses

We investigate how molecular and interfacial organization, ionic redistribution and mechanical deformation contribute to functional responses in soft materials. Current work focuses on interpreting deformation-dependent electrical signals without assuming an intrinsic piezoelectric mechanism. Earlier research on responsive gels, emulsions and polymeric systems provides a related foundation in stimulus-dependent material behavior.

Self-assembled ionic materialsMechanoelectric responseElectrokinetic mechanismsStimuli-responsive systems

Polarized light micrograph of a textured aminomethylpropanol oleic acid water gel showing birefringent organized domains — Polarized-light microscopy of a soft gel formed from aminomethylpropanol, oleic acid, and water, investigated as a mechanoelectric material.

Micrograph showing elongated fibrillar structures in an arginine–dodecanoic-acid soft paste — Fibrillar structures in a paste formed by mixing arginine and dodecanoic acid in water. Assemblies of this material were used to investigate shear-direction-dependent mechanoelectric responses with grooved electrodes.

Conceptual framework

From molecular interactions to phase behavior

Preferential solvation and intermolecular association can generate compositional heterogeneity before macroscopic demixing. This schematic represents one possible progression in complex aqueous mixtures; not every system traverses these stages or follows the same kinetics.

Adapted conceptually from Pensini and Marangoni, Current Opinion in Colloid & Interface Science (2026), doi:10.1016/j.cocis.2026.102046 (CC BY 4.0). Schematic, not experimental data.

How we investigate these questions

Research Approaches

We combine experimental characterization with thermodynamics and molecular modelling to connect molecular interactions and mesoscale organization to observable behavior. Methods are selected according to the physical questions under investigation.

Scattering & spectroscopy

Small-angle X-ray and neutron scattering (SAXS/SANS) probe structure and heterogeneity across length scales. Fourier-transform infrared spectroscopy (FTIR) and X-ray absorption spectroscopy (XAS/XAFS) help examine molecular environments and interactions at interfaces.

Microscopy & physical characterization

Optical, polarized-light and confocal microscopy resolve dispersed phases and organized materials. Interfacial characterization, sorption and transport experiments, and electromechanical measurements connect microscopic structure to measurable response.

Thermodynamics & computation

We use thermodynamic analysis and COSMO-RS to investigate nonideal mixing and preferential interactions, together with density functional theory (DFT) calculations. Molecular dynamics (MD) simulations are an expanding component of our work, used to probe solvation, association and structural dynamics.

Scientific continuity

Across interfaces, phases and materials

The three directions are interconnected. Molecular association can change phase behavior; phase separation and chemical transformation can modify transport; and interfacial structure and ionic motion can influence the response of soft materials. We investigate these connections while distinguishing observed behavior from proposed mechanisms.