We use critical Casimir forces, together with new colloidal building blocks to assemble complex colloidal phases – from colloidal liquids and crystals to colloidal molecules. We link patchy particles into complex superstructures by precise control of their interactions. The direct imaging of the assembly process gives insight into the statistical physics of structure formation that also underlies the formation of molecular structures. These micron and nanoscale structures exhibit unexpected optical, mechanical and chemical properties of interest for future materials.
Equilibrium gels
Particles of distinct valency can assemble in networks in an equilibrium process. The networks are called “equilibrium gels” and their properties can be predicted by equilibrium thermodynamics. We use patchy particles to experimentally assemble and analyse equilibrium gels. Read more …
Colloidal Graphene
Simple colloids assemble into close-packed crystal structures, while open crystal structures are needed for photonic and phononic bandgap materials. Here, we assemble patchy particles into the open honeycomb lattice, producing the analogue of atomic graphene. Read more …
Colloidal Polymer assembly on surfaces
We investigate the growth of chains of colloidal di-patch particles on a surface. These “colloidal polymers” are assembled in equilibrium by tuning the attraction of the patches via critical Casimir forces. Read more ..
Check out our paper in Phys. Rev. Lett.
Colloidal Molecules
We assemble patchy colloidal particles into analogues of molecules. Divalent and tetravalent particles form colloidal polymers and colloidal carbon compounds with dynamics surprisingly similar to their atomic counterparts Read more …
See also our paper in Nature Comm.
Gelation
We obtain insight into the ubiquitous gelation phenomenon. Critical Casimir forces allow us to adjust the particle interactions to follow the particle-scale aggregation process in-situ. Read more …
See also our recent publication in Nature communications (2020)
Protein aggregation is central to biology, health and food science. We use protein microparticles to follow the protein aggregation process on experimentally accessible large length and time scales. Read more …
See our recent publication in Science of Food (2021)
Liquid Nucleation
We nucleate colloidal liquids from the colloidal gas phase and follow the nucleation process at the particle scale. These observations allow direct measurement of the curvature-dependant surface tension of these small, nuclei. Read more …
Check out our PRL article (2018)
Colloidal Phase transitions
We control colloidal interactions by critical Casimir forces to assemble colloidal particles into equilibrium phases: gas -liquid – crystals, and investigate phase transitions. Read more …
Also see our paper in Nature Comm.