Investigating 3D-printed structures in real time

Scientists used ultrabright x-rays to watch the developing structure of a 3D-printed part evolve during the printing process.

A team of scientists working at the National Synchrotron Light Source II (NSLS-II) at the U.S. Department of Energy’s (DOE’s) Brookhaven National Laboratory has designed an apparatus that can take simultaneous temperature and x-ray scattering measurements of a 3D printing process in real time, and have used it to gather information that may improve finished 3D products made from a large variety of plastics. This study could broaden the scope of the printing process in the manufacturing industry and is also an important step forward for Brookhaven Lab and Stony Brook University’s collaborative advanced manufacturing program.

The researchers were studying a 3D printing method called fused filament fabrication, now better known as material extrusion. In material extrusion, filaments of a thermoplastic—a polymer that softens when heated and hardens when cooled—are melted and deposited in many thin layers to build a finished structure. This approach is often called “additive” manufacturing because the layers add up to produce the final product.

Read more on the NSLS-II website

Image: The photo shows the research team, (from front to back) Yu-Chung Lin, Miriam Rafailovich, Aniket Raut, Guillaume Freychet, Mikhail Zhernenkov, and Yuval Shmueli (not pictured), placing the 3D printer into the chamber of the Soft Matter Interfaces (SMI) beamline at Brookhaven Lab’s National Synchrotron Light Source II (NSLS-II).

Note: this photo was taken in March 2020, prior to current COVID-19 social distancing guidelines.

How new materials increase the efficiency of direct ethanol fuel cells

A group from Brazil and an HZB team have investigated a novel composite membrane for ethanol fuel cells. It consists of the polymer Nafion, in which nanoparticles of a titanium compound are embedded by the rarely explored melt extrusion process. At BESSY II they were able to observe in detail, how the nanoparticles in the Nafion matrix are distributed and how they contribute to increase proton conductivity.

Ethanol has five times higher volumetric energy density (6.7 kWh/L) than hydrogen (1.3 kWh/L) and can be used safely in fuel cells for power generation. In Brazil in particular there is great interest in better fuel cells for ethanol as all the country distributes low-cost ethanol produced in a renewable way from sugar cane. Theoretically, the efficiency of an ethanol fuel cell should be 96 percent, but in practice at the highest power density it is only 30 percent, due to a variety of reasons. So there is great room for improvements.

Nafion with nanoparticles

A team led by Dr. Bruno Matos from the Brazilian research institute IPEN is therefore investigating novel composite membranes for direct ethanol fuel cells. A promising solution is tailoring new polymer-based composite electrolyte materials to replace the state-of-the-art polymer electrolyte such as Nafion. Matos and his team use melt extrusion process to produce composite membranes based on Nafion with additional titanate nanoparticles, which have been functionalized with sulfonic acid groups.

Read more on BESSY II (at HZB) website

Image: The material consists of Nafion with embedded nanoparticles.

Credit: © B.Matos/IPEN