Title: From Grove’s cell to the Proton Exchange Membrane (PEMFC). Determining efficiency parameters. Student: Andrea Mateo Tarafa Date: June 2013 Supervisor/s: Dr. Pere Lluís Cabot Departament of Physical Chemistry

Fuel cells are characteristic for being electrochemical systems that allow electrical energy obtaining from the reaction between a fuel gas and an oxidant gas. These devices sparked electrochemical and new technology researchers’ interest due they are very efficiency and environmentally friendly devices. The birth of which nowadays is considered the first fuel cell took place in 1839, when Sir William Robert Grove published an account of his studies with the Gaseous Voltaic Battery. After decades of investigation and the application of new discoveries as the gas diffusion or the use of suitable catalysts, the consequence is the creation of new fuel cells designs and the existence of a research field under expansion that offers the possibility of improving the use of clean energy. This work has focused on the design and construction of a first Grove’s invention replica and the comparison of the voltage, current and power performances at different temperatures between this and a nowadays proton exchange membrane fuel cell. Besides this goal, this work has targeted towards suggesting improvements in Grove’s cell design or stating the need of catalysts for this kind of reactions at low temperatures. Both systems allowed the study of hydrogen oxidation reaction in

H2(g) → 2H+ + 2e- and the oxygen reduction reaction in

1/2O2(g) + 2H+ + 2e- → H2O(l) being the global reaction

H2(g) + 1/2O2(g) → H2O(l) as it can be observed the electrochemical phenomena that are expected to occur in the electrode- interface in that kind of reactions. To achieve the mentioned goals, the Grove’s cell replica was built up following the information of his publications and the reactive gases were generated inside the cell by acidulated water electrolysis. Once the gases were confined on corresponding electrode space, the device was connected to an external circuit, in which different value external resistances were connected so the voltage difference between resistances was measured. From voltage and external resistance values, cell voltage vs. cell current and cell power vs. cell current plots could be created. For knowing the nowadays PEMFC performances, the established action protocol was followed to runt the station and obtain the same plots analyzed on Grove’s cell so differences between systems could be detected. Finally, the work expresses the efficiency that both devices and show and so the efficiency that H2-O2 reaction system offer.