Fabrication of Multi-Metallic Frameworks with Specific Surface Areas Tailored for Catalysis of Surface Based Reactions

Abstract

Fabrication of catalysts is important with regards to the extraction of energy from future fuel sources. In order to enhance the understanding and improve reactions associated with this extraction, the control of size, shape, morphology and composition is crucial. Noble metals such as platinum, palladium, gold, and ruthenium are active for both electrocatalysis and heterogeneous catalysis, however the price of materials containing these metals is high, hence the creation of catalysts with large specific surface areas is essential. Electrodeposition at high overpotential is able to create open surfaces of a 3-D high surface area nature. Here we use the dynamic hydrogen bubble templating method to fabricate highly porous and stable multi-metal frameworks. By using, copper, a relatively cheap metal, as the major component and incorporating precious noble metals, frameworks of both varying compositions and morphologies can be produced. Most importantly the porous and nanostructured nature results in increased roughness factors and therefore increases in the specific surface area and material utilisation. Through variation in the deposition parameters composition, shape and pore size is able to be controlled. These frameworks of materials were tested for surface based catalysis reactions and have shown enhanced ability towards the hydrogen evolution reaction (HER) and the oxygen reduction reaction (ORR). It is shown that subtle variations in surface chemistry greatly affect catalytic activity. This is linked to both structural and electronic effects from the combination of the metals. Figure 1