N. Dutta, N. Roy Choudhury, S. Subianto, M. Mistry
Today most of our energy supply comes from non-renewable energy resources such as fossil fuels, but there is an increasing drive towards the use of more environmentally friendly, renewable energy source. Of these alternative energies, hydrogen fuel cells are attracting significant attention due to their potential as a “clean” fuel, and in particular the polymer electrolyte membrane fuel cells (PEMFC) represent a credible alternative to fossil fuels especially in portable applications such as the automotive industry. Currently, there are significant research interest in raising the operating temperature of these PEMFCs to 120-140°C, as this increases the catalyst’s CO tolerance and improves electrode kinetics and efficiency. In our study, POSS was successfully functionalised with multiple sulfonic acid groups and when incorporated into proton conducting membranes such as NafionTM, the resultant composite membranes remained transparent and increase its glass transition temperature and introduce greater mechanical stability at high temperatures. It also showed a 20% increase in proton conductivity at room temperature and 100% relative humidity with a very small loading of POSS (1-2%).We have also incorporated ionic liquids in a suitable polymer matrix to form a novel supported liquid membrane that exhibits proton conduct in non-humidifying conditions at high temperatures.