Modification of Metal Oxides with Extreme Points of Zero Charge By Non-Thermal RF Plasma

The effect of non-thermal RF plasma modification on the point of zero charge (PZC) of magnesia and silica has been explored. It has been previously established that plasma modification effectively lowers the PZC of alumina, an effect attributed to adsorbed gas species. The purpose of this study is to build on that work, answering the question, "Can non-thermal RF plasma moderate more extreme PZC?"

In this work, samples were modified with air and oxygen plasma, before PZC analysis. In order to further explore the effect of this treatment, Fourier-transform infrared spectroscopy (FTIR) studies were performed, to assess potential changes to adsorbed species.

Ultimately these supports will be decorated with catalytic metals via strong electrostatic adsorption (SEA), the efficacy of which (in terms of overall loading, particle size, and bond strength) is dependent on the material's PZC. Effective modification could open up previously unattractive supports for use with SEA.