PEMFC is a promising and energy-efficient technology for use in vehicles, as well as portable and stationary power applications, which convert chemical energy associated with molecules to electrical energy. The zero tail gas emission from a PEMFC, which uses H2 as fuel causes less sabotage to the environment. But the high cost associated with the noble metal catalyst such as Platinum and Palladium which is used in the membrane electrode assembly (MEA) which is observed as the heart of the PEMFC limits mass production and commercialization of these fuel cell systems despite
the numerous advantages it posses.
O
ver the years the structure and composition of the ‘electrode’ has been significantly altered, from utilizing platinum black films with a platinum loading of 10 g Pt/cm2 in the 1970s to present-day platinum/PGM nanoparticle coated carbon black particles (Pt/C) that use about 0.3 mg Pt/cm2. However, these Pt/C catalysts have a shortcoming in durability, attributed to the corrosion of the carbon support and the catalyst's loss of activity because of the intermittent start up and shut down of the fuel cell vehicle.
T
o meet the Department of Energy (DOE) requirements for the electrocatalyst like loading of the catalyst material (platinum group metal (PGM) < 0.125 mg/cm2), durability of the electrocatalyst (< 40% loss of initial catalytic activity after 30k cycles), and mass activity (> 0.44 A/mgPt @ 0.9V), our group has laid down the following goals in the catalyst research which are:
Minimize the cost of the cell by bringing down the usage of Pt metal as catalyst
Obtain higher electrochemically active surface areas (ECSA)
Enhance the sluggish oxygen reduction reaction (ORR)
To achieve the above goal's our objective is to develop a bimetallic/trimetallic carbon-less nanostructured thin film electrocatalyst with enhanced activity and low Pt loading by adopting the paradigm of Pt rich skin on nanostructured metallic surfaces. Such a thin film architecture of the electrocatalyst could lead to a reduction of the Pt loading and ameliorate issues with corrosion of the underlying support material during startup/shutdown.