Porous High Entropy Alloy as Efficient Electrocatalysts for Water Splitting

High Entropy Alloy (HEA) has attracted attention for its excellent corrosion resistance and adjustable properties due to four core effects. When a non-noble-metal such as Fe, Co, and Ni is used to form the HEA composition, better catalyst properties are exhibited than using each element. In addition, HEAs have good corrosion resistance and stability due to the lattice distortion effect and the slow diffusion effect. Therefore, HEAs are expected to be a key to solving the high price of catalysts for hydrogen production.<br/>In this study, The HEA composition was designed by predicting the composition of the single phase through the CALPHAD program by referring to the Volcano plot. HEA powders were fabricated via a powder metallurgy process. The prepared porous HEAs exhibited remarkable performance in the oxygen evolution reaction and the hydrogen evolution reaction due to the adequate adsorption energy of hydrogen or oxygen atoms being adjusted by the cocktail effect. Based on these results, it is expected that HEAs electrocatalysts are possible to use large-scale alkaline water electrolysis electrode.<br/><br/><b>Acknowledgement</b><br/>This work was supported by the National Research Foundation of Korean (NRF) grant funded by the Korea government (Ministry of Science and ICT) (2021R1F1A1058854) and the Development of 100 nm sized tungsten based material out of scrap and tool manufacturing technology using scrap for precision machining (20011520) funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea).