Workgroup Nanofluidics

In the "Nanofluidics" working group, ceramic ultra- and nanofiltration membranes based on nanoporous metal oxides as well as zeolite membranes for gas separation have been developed and characterized for many years. Sol-gel processes and hydrothermal syntheses as well as special coating techniques are used for the fabrication. The membranes developed, based on MFI and beta zeolites, are capable of separating complex gas mixtures such as natural gas into their individual components. In addition to the fabrication and structural investigation of the membranes, the characterization of the interactions with gas molecules and, in this context, the development of structure-function relationships is the object of research here. For the characterization of the liquid filtration membranes, an automated electrokinetic measurement technique, unique in its functional range, was installed. Molecules, atoms and ions adsorbed on the membrane surfaces significantly influence the flow behavior of the fluids as well as the filtration sensitivity and selectivity. Electrokinetic measurements allow non-destructive investigation of the resulting effects. An "electrokinetic generator" was built as a demonstrator for potential future energy harvesting applications.

Representation of a meander structure.

Another focus is 3D-structured microfluidic channel systems in ceramic components using textile structures. Within the framework of the AiF project ChannelTex, ceramic surfaces of 3D channels are therefore functionalized or provided with catalytic or sensoric layers at IESM.

Furthermore, sensitive layers for ISFET-based sensors (ISFET = ion-selective field-effect transistors) are being developed in the Nanofluidics working group. These can be used as cost-effective and robust sensors in the liquid phase. Examples of applications here include pH sensors for cooling lubricants or drilling fluids.