Gamma-alumina for Catalyst Bonding (IMAGE) DOE/Pacific Northwest National Laboratory Caption PNNL scientists looking for better vehicle emission treatments have discovered how potential catalyst materials are constructed. Researchers found that, in the presence of water, aluminum ions (gray) on the surface of alumina bond to six oxygen ions (red). Heating removes the water and leaves some aluminum ions with only five oxygen ions. This creates a bonding site for the NOx-removing catalyst barium oxide. Credit Pacific Northwest National Laboratory Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.