Efficient Integrated Electrode Enables High-Current Operation and Excellent Stability for Green Hydrogen Production

Abstract

Generating green hydrogen through proton exchange membrane electrolyzer cells (PEMECs) is promising to build future sustainable energy systems. Operating PEMECs at high current densities with high efficiency is a realistic strategy to reduce the capital costs of PEMECs and increase their sustainability. Herein, an Ir-integrated electrode was developed via facile electrodeposition as an efficient anode for PEMECs, successfully achieving high-current operation of up to 6 A/cm 2 . More importantly, the electrode shows excellent stability under an ultrahigh current density of 5 A/cm 2 , showing almost no performance loss after the stability test. Further studies indicate that a platinum protection layer on Ti substrates plays a crucial role in superior performance and stability, which not only provides electrodes with improved electrical conductivity resulting in improved catalyst activity but also enhances the crack-free catalyst layer achieving catalysts' adhesion improvement to the substrate and prevents substrate oxidation. With platinum, the cell voltage can be improved by 33, 59, and 87 mV at current densities of 2, 4, and 6 A/cm 2 , respectively. Overall, considering efficient high-current operation capability, remarkable stability, and significantly simplified and low-cost fabrication process with easy scalability, the developed integrated electrodes are believed to have great potential in future sustainable energy systems.

Tuning the In-Plane Electrical Conductivity and Performance of the Low Ir Anode in a Proton Exchange Membrane Water Electrolyzer

“…With thicker gold film, the bilayer anodes show smaller ohmic resistance; however, a thicker gold layer leads to higher mass transport resistance under high current density in comparison to the anode with 20 nm gold. This must be related to the more compact gold film which impedes the water access and oxygen removal compared to the porous thin film. , The EIS data further verify the high mass transport resistance (Figure S7 and Table S3). It is noted that the single-layer anode shows larger mass transport polarization compared to the bilayer anode (20 nm gold).…”