Recycled Anode Materials from Manufacturing Industry for Anion Exchange Membrane Water Electrolyzer

Abstract

As the energy industries, such as secondary batteries and fuel cells, expand rapidly, the demand for transition metals used as electrode materials is increasing, which has led to a rise in their prices. One promising strategy to address these challenges is upcycling, which involves recycling transition metal-based waste from various industries. In this study, a heterostructure electrocatalyst for anion exchange membrane water electrolysis is developed by upcycling iron-based waste from the automotive industry. The iron-based swarf is converted into single-phase Fe₂O₃ by removing surface impurities through calcination in air. Subsequently, NiFe-LDH is formed via sequential hydrothermal synthesis, resulting in NiFe-LDH/Fe₂O₃ heterostructured electrocatalysts. The hetero-interface between NiFe-LDH and Fe₂O₃ significantly reduced the electrochemical activation barrier, enhancing oxygen evolution reaction (OER) activity and, furthermore, achieving high-performance AEMWE. This approach not only reduces waste but also provides a cost-effective alternative to traditional materials, highlighting the potential for sustainable and efficient energy solutions.