Research

Research work at the Radacsi Group NanoMaterials Laboratory

1. Solid acid fuel cells

Fuel cells remain the most efficient means of converting chemical energy to electrical energy. We are developing a new fuel cell type, based on the solid acid electrolyte CsH2PO4 (cesium dihydrogen phosphate). Such solid acid fuel cells (SAFCs) operate at intermediate temperatures (~250°C), and have low cost, high durability, easy start/stop cycling, fuel flexibility, and simple system design. SAFCs combine the advantages of low- and high- temperature fuel cells. The high impurity tolerance of SAFCs enables effective operation of these electrochemical cells on a wide range of reformed fuels. The temperature is sufficiently low, however, that low cost of auxiliary components and easy thermal cycling are possible with long-term thermal stability. We are using nanofabrication to advance SAFC technology, making it competitive to other fuel cell technologies.

2. Li-ion batteries

Energy storage is a key component for providing clean and reliable energy. A promising method for fabricating the future batteries is the assembly of nanostructured batteries. Electrospinning and 3D nanoprinting are simple and inexpensive approaches for fabricating uniform nanostructured materials. We are fabricating cathode/anode materials for Li-ions batteries.

3. Artificial skin

Our goal is to make a stretchable, self-healing sensor-system that is similar to our skin. Applications range from robotics to electronics and medical applications, like recovering burned skin areas, where patients are able to feel again with their new skin. We are using cutting-edge research for fabricating stretchable, self-healing sensor-system that has a nanofibrous structure with biological cells (artificial skin). We are using electrospinning combined with 3D (nano)printing for designing in the lab a skin that is similar to ours.

Tools

Electrospinning

Electrospinning is a technique to fabricate fibers with nano-sized diameters by creating a high voltage potential across a solvent-polymer solution stream coming out of a nozzle. The electrostatic repulsion from the high voltage overcomes the surface tension of the stream. This causes the liquid to stretch and spew out as an elongated cone structure, called the Taylor Cone. Before reaching the collector, the solvent dries up and fibers of the polymer are deposited on the collector surface with uniform nano-scaled diameters as a result of the elongation process caused by the high voltage. These nanofibers are of great interest to fuel cells as their characteristic high surface area due to their nano-sized diameters provide great conductivity pathways in the electrolyte as it allows greater movement due to the optimization of contact between the electrolyte and the passing ions.

3D nanoprinting

We are using a prototype of a new type of 3D nanoprinter. Our printer can make structures down to 30 nm size.

Schematics of electrospinning with a nozzle
Schematics of electrospinning with a nozzle
Illustration of 3D nanoprinting
Illustration of 3D nanoprinting