Spent Fuel Cell Electrocatalyst Recycling through Potentiodynamic Dissolution of Platinum

Abstract

Large-scale commercialization and sustainable growth of proton exchange membrane fuel cells (PEMFCs) technology is throttled largely by high cost and scarce nature of Pt, the most preferred electrocatalyst for both the anode and cathode reactions. Recycling of the electrocatalyst from spent PEMFC electrodes through a commercially scalable and environmentally benign process is of significant interest. Here, we present technical details of a closed loop recycling of spent electrocatalyst from a PEMFC electrode. The process includes electrochemical dissolution of the Pt nanoparticles in dilute acidic bath, precipitation of the dissolved Pt in form of a chloride-free Pt precursor and synthesis of carbon supported Pt (Pt/C) electrocatalyst through reduction of the Pt precursor. The presentation will highlight some of the studies from our group aiming to enhance the Pt dissolution efficiency and to optimize the process steps for synthesis of the Pt/C electrocatalyst from the dissolved P. With a demonstrated recovery efficiency >90%, the process may be utilized for large-scale recycling of the spent electrocatalysts, especially suitable for PEMFC electrodes. References R Sharma, S Gyergyek, P Morgan and S M Andersen, Electrochem. Soc., 2020, 167 (2): p. 024521. R Sharma, K R Nielsen, P B Lund, S B Simonsen, L G Madsen, and S M Andersen, ChemElectroChem, 2019. 6(17): p. 4471-4482. R Sharma, S J Andreasen, J Chamier, and S M Andersen, Electrochem. Soc., 2019. 166(13): p. F963-F970. R Sharma, S B Simonsen, P Morgen, and S M Andersen, Acta, 2019. 321: p. 134662. R Sharma, S Gyergyek and S M Andersen, ChemSusChem 2018, 11(21), 3742-3750 R Sharma, Y Wang, F Li, J Chamier, and S M Andersen, ACS Appl. Energy Mater., 2019. 2(9): p. 6875-6882. R Sharma, P. Morgan and S M Andersen, PCCP, 2020 (Accepted manuscript), https://doi.org/10.1039/C9CP06066A Figure 1