Advancing Hydroxide Exchange Membrane Fuel Cells with Atomically Dispersed Ir on Mo2C Catalyst
Key Ideas
- Hydroxide exchange membrane fuel cells (HEMFCs) can achieve cost-effectiveness through the use of atomically dispersed Ir on Mo2C catalyst as a highly active and stable alternative to traditional Pt-based catalysts.
- The IrSA-Mo2C/C catalyst demonstrated excellent activity for hydrogen oxidation reaction (HOR) with high specific exchange current density and mass activity, outperforming current state-of-the-art PtRu/C catalysts.
- By utilizing a low anode platinum group metal (PGM) loading, the IrSA-Mo2C/C HEMFC achieved a high peak power density and displayed exceptional stability over 120 hours of continuous operation and 30,000 cycles of accelerated durability test.
- Density functional theory (DFT) calculations highlighted the unique d-orbital behavior of IrSA-Mo2C in enhancing hydroxide and hydrogen binding, showcasing the advantages of atomically dispersed metal catalysts on carbides for electrocatalysis.
The article discusses the advancement of Hydroxide Exchange Membrane Fuel Cells (HEMFCs) by introducing an atomically dispersed Ir on Mo2C catalyst for efficient hydrogen oxidation reaction (HOR) in alkaline electrolyte. Traditional HEMFC anodes rely heavily on platinum group metals (PGMs), leading to increased costs. The IrSA-Mo2C/C catalyst, with Mo2C NPs as hosts for Ir atoms, exhibited superior activity and stability compared to Pt-based catalysts. It achieved high specific exchange current density and mass activity, surpassing the performance of PtRu/C catalysts. By using low PGM loading, the IrSA-Mo2C/C HEMFC demonstrated a remarkable peak power density and long-term stability through various tests. Density functional theory (DFT) calculations illustrated the distinctive d-orbital characteristics of IrSA-Mo2C, contributing to enhanced hydroxide and hydrogen binding. This study emphasizes the potential of atomically dispersed metal catalysts on carbides in optimizing electrocatalytic performance.