Descripción del proyecto
Vehicular transportation is responsible for a third of greenhouse gas emissions globally. Hydrogen fuel cells, comprising of a proton exchange membrane (PEM) coated with catalyst layers (CLs) and sandwiched between gas diffusion layers, generate electrical energy with high efficiency and zero emission. The concern regarding a potential ban by the European Union on the use of per- and polyfluoroalkyl-type ‘forever chemicals’ that are currently used as PEMs and CL ionomers prompts us to seek sustainable alternatives, such as aromatic hydrocarbons (AH).
Significant progress has been made to use AHs as PEMs, due to their excellent thermal stability and eco-friendly synthesis. However, presently the specific adsorption of aromatic constituents on the noble metal catalyst and low gas permeability in the CL causes a performance penalty, thus aggravating the use of AHs as catalyst ionomer.
The aim of this project is to address these issues by developing a new class of catalyst ionomers based on AH polymers with intrinsic microporosity (PIMs). AH PIMs are expected to improve FC performance: as highly gas permeable ionomer in the CL, they facilitate chemical reactions and improve interfacial compatibility between CLs and PEM.
Using chemically durable polyphenylenes as scaffold we propose to synthesize a range of AH PIMs with enhanced gas permeability and chemical durability (objective 1-2, University of Yamanashi). Catalyst ink formulations will be prepared and coated on both sides of best-in-class AH-based PEMs to obtain catalyst coated membranes (CCMs) with optimized morphology, electrochemical surface area, electrochemical activity and ionic conductivity (objective 3-4). Finally, the performance and durability of the novel CCMs will be evaluated in the single fuel cell at University of Freiburg (objective 5). This project will contribute to the increased market penetration of the fuel cell technology and to the realisation of a more sustainable society.