The development of high-performance, low-content Ir catalysts is essential for enhancing the cost efficiency of anode catalysts and accelerating the widespread adoption of proton exchange membrane water electrolysis (PEMWE) for sustainable hydrogen production. Existing strategies, such as reducing catalyst particle size and alloying with non-precious metals, have shown limited success in surpassing the intrinsic activity of commercial IrO catalysts. This study presents a novel synthesis strategy for IrO catalyst using NaCl as a structure modifier, delivering a catalyst (IrO_NaCl) that achieves an impressive current density of 2.
View Article and Find Full Text PDFElectrocatalysis is a key driver in promoting the paradigm shift from the current fossil-fuel-based hydrocarbon economy to a renewable-energy-driven hydrogen economy. The success of electrocatalysis hinges primarily on achieving high catalytic selectivity along with maximum activity and sustained longevity. Many electrochemical reactions proceed through multiple pathways, requiring highly selective catalysts.
View Article and Find Full Text PDFOxygen reduction reaction (ORR) plays a pivotal role in electrochemical energy conversion and commodity chemical production. Oxygen reduction involving a complete four-electron (4e-) transfer is important for the efficient operation of polymer electrolyte fuel cells, whereas the ORR with a partial 2e- transfer can serve as a versatile method for producing industrially important hydrogen peroxide (H2O2). For both the 4e- and 2e- pathway ORR, platinum-group metals (PGMs) have been materials of prevalent choice owing to their high intrinsic activity, but they are costly and scarce.
View Article and Find Full Text PDFLignin is a major component of lignocellulosic biomass. Although it is highly recalcitrant to break down, it is a very abundant natural source of valuable aromatic carbons. Thus, the effective valorisation of lignin is crucial for realising a sustainable biorefinery chain.
View Article and Find Full Text PDFIron-nitrogen on carbon (Fe-N/C) catalysts have emerged as promising nonprecious metal catalysts (NPMCs) for oxygen reduction reaction (ORR) in energy conversion and storage devices. It has been widely suggested that an active site structure for Fe-N/C catalysts contains Fe-N coordination. However, the preparation of high-performance Fe-N/C catalysts mostly involves a high-temperature pyrolysis step, which generates not only catalytically active Fe-N sites, but also less active large iron-based particles.
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