Category Chemistry/Nanotechnology

Modeling how methanol interacts with platinum catalysts inside fuel cells in realistic environments becomes even more complicated because distances between the atoms can change as molecules dance near the charged surface. Credit: Manos Mavrikakis

Using a unique combination of advanced computational methods, University of Wisconsin-Madison chemical engineers have demystified some of the complex catalytic chemistry in fuel cells – an advance that brings cost-effective fuel cells closer to reality. “Understanding reaction mechanisms is the first step toward eventually replacing expensive platinum in fuel cells with a cheaper material,” says Prof. Manos Mavrikakis.

Fuel cells generate electricity by combining electrons and protons — provided by a chemical fuel such as methanol – with oxygen fr...

Nanofiber mat electrode (John Russell / Vanderbilt)

The project is part of a $13 million Department of Energy program to advance fuel cell performance and durability and hydrogen storage technologies announced last month. The $4.5 million collaboration is based on a new nanofiber mat technology developed by Peter Pintauro, the H. Eugene McBrayer Professor of Chemical Engineering at Vanderbilt, that replaces the conventional electrodes used in fuel cells. The nanofiber electrodes boost the power output of fuel cells by 30% while being less expensive and more durable than conventional catalyst layers...

Individual crystals of synthetic zhemchuzhnikovite, prepared by Igor Huski?, McGill University. Credit: Igor Huski?, Friš?i? Research Group, McGill University

A surprising discovery reveals that MOFs also exist in nature – albeit in the form of rare minerals found so far only in Siberian coal mines. Metal-organic frameworks are human-made materials introduced in the 1990s, and researchers are working on ways to use them as molecular sponges for applications such as H storage, C sequestration, or photovoltaics.

The finding “completely changes the normal view of these highly popular materials as solely artificial, ‘designer’ solids,” says Tomislav Friščić, an associate professor of chemistry at McGill University in Montreal...

A 32-face 3-D truncated icosahedron mesh was created to test the simulation’s ability to precisely construct complex geometries. The SEM image of the final experimental product (left) was highly consistent with the structure predicted by the virtual SEM image (center) and the simulated design model (right). (hi-res image)

Focused electron beam induced deposition, or FEBID can essentially 3D print at the nanoscale. FEBID uses an electron beam from a scanning electron microscope to condense gaseous precursor molecules into a solid deposit on a surface. Previously, this method was laborious, prone to errors and impractical for creating complex structures larger than a few nanometers...