Abstract
In this study, various methods to study individual electrodes in polymer electrolyte membrane cells are reviewed and a novel reference electrode design is developed for a laboratory scale single cell polymer electrolyte membrane water electrolyser. The design uses an internal pseudo-reference electrode which is proven to enable galvanostatic electrochemical impedance spectroscopy studies. The setup is used to study the state-of-the-art electrode materials with high loadings in a start-stop cycling durability test. The cycled catalyst layers are characterized ex-situ with SEM, TEM and XRD. As a result, on the anode the mass transport resistance increases, the macro porosity increases and a structural change from amorphous IrOx toward crystalline IrO2 is detected. On the cathode the platinum particle size increases and an intensifying corrosion phenomenon is detected. In overall, this degradation has still low effect on the full cell performance during the studied 1750 hours. However, there is a clear indication that if the start-stop cycling is further continued, the cell will experience a dramatic performance loss much sooner than when operating it in a constant current mode.
| Original language | English |
|---|---|
| Pages (from-to) | F1326-F1336 |
| Journal | Journal of the Electrochemical Society |
| Volume | 166 |
| Issue number | 16 |
| DOIs | |
| Publication status | Published - 16 Dec 2019 |
| MoE publication type | A1 Journal article-refereed |
Funding
The authors would like to thank the Academy of Finland (DEMEC (285693), SUPER (292554) and CloseLoop (303452) projects) for funding this work and ITM Power for providing the experimental setup for carrying out the PEM electrolyser measurements. Glen Forde is acknowledged for taking the photographs in Fig. 1. Miikka Jokinen is acknowledged for his help in fitting the impedance spectra and Dr. Nick van Dijk and Taina Rauhala for the fruitful discussions. Dr. Jani Seitsonen, Syed Muhammad Farhan Ali and Lijun Fan are acknowledged for their help in TEM imaging. This study made use of the facilities of Aalto University Nanomicroscopy Center (Aalto-NMC) and Bioeconomy and RawMatters Research Infrastructures (Aalto-RaMI). The authors would like to thank the Academy of Finland (DE-MEC (285693), SUPER (292554) and CloseLoop (303452) projects) for funding this work and ITM Power for providing the experimental setup for carrying out the PEM electrolyser measurements. Glen Forde is acknowledged for taking the photographs in Fig. 1. Miikka Jokinen is acknowledged for his help in fitting the impedance spectra and Dr. Nick van Dijk and Taina Rauhala for the fruitful discussions. Dr. Jani Seitsonen, Syed Muhammad Farhan Ali and Lijun Fan are acknowledged for their help in TEM imaging. This study made use of the facilities of Aalto University Nanomicroscopy Center (Aalto-NMC) and Bioeconomy and RawMatters Research Infrastructures (Aalto-RaMI).
