Low Pt loading thin cathode catalyst layer by Reactive Spray Deposition Technology

摘要

The Reactive Spray Deposition Technology (RSDT) process allows for composite electrode layer formation and low loading electrocatalysts. The RSDT process provides the production means necessary to develop next generation thin, low platinum or alloyed catalyst layers for PEM MEA's. A gradient with controlled porosity and controlled distribution of both platinum and ionomer across the catalyst layer is possible with the RSDT process. Platinum particles are created directly from metal vapours whose size is controlled by the process. In our design, a platinum sublayer (100 nm) was deposited directly on a Nafion~R NRE211 membrane as a columnar structure. After the sub-layer, the platinum loading was reduced in a co-deposited layer of Pt-Nafion (ionomer)-carbon with the lowest loading closest to the GDL. The combined loading of both layers was <0.05mg/cm~2 Pt with this approach. The manufactured catalyst layer has a performance of 0.65V at 1 A/cm~2 with 0.05mg/cm~2 Pt loading using oxygen.