Innovative Chemistry for Electrocatalvsts and Conductive Materials

In electrocatalysis applications support materials are required that provide an electrically conductive layer to form electrodes and support active catalyst materials. Under the stringent conditions found in fuel cells, where polymeric acid electrolytes are often used, these materials must be resilient towards both acid-induced and electrochemically induced dissolution. Conducting carbon-based layers, for example, whilst able to be conveniently and cheaply formed, are easily oxidised to CO2 at high potential.

The aim of this project is to understand the reason why certain materials are acid-resilient and why others are not and then to discover new, conductive acid-resilient conductive materials.

We will study two classes of inorganic materials: carbides and oxides.

This will make use of Warwick's expertise in solution-based synthesis of mixed oxides for preparing unusual compositions as fine powders. We will explore hydrothermal synthesis under acid conditions for compositions such as iridates, tantalates, niobates and ruthenates containing alkali- and alkali-earth cations with the aim of isolating acid-resilient materials. Carbide synthesis will use precursor decomposition methods, and we explore the preparation of mixed-metal carbides and carbonitrides, including metals such as niobium, tantalum, tungsten, iridium and platinum.

We will characterise the materials using a wide range of advanced physical characterisation methods, including diffraction, spectroscopy and microscopy methods at Warwick. Dissolution will be studied using ICP analysis of effluent solutions. The use of X-ray absorption spectroscopy analysis at Diamond Light Source will be investigated to examine highly dilute solution species produced on dissolution of materials as a function of pH and electrochemical potential. Electrochemical characterisation will be performed at JM's Technology Centre.