Multifunctional Catalysts Based on High-Entropy Transition Metal Alloys

Abstract

High-entropy alloys were produced by centrifugal self-propagating high-temperature synthesis and used as precursors for preparation of catalysts for CO and propane deep oxidation and CO₂ hydrogenation. The precursors were converted into catalysts by aluminum leaching and stabilization with hydrogen peroxide solution. Prepared FeCoNiCu, FeCoNiCuMo, FeCoNiCuMn, and FeCoNiCuCr catalysts were characterized by XRD, SEM/EDS, and BET methods and tested in the processes of deep oxidation of CO and propane and methanation of CO₂. The highest CO₂ conversion, 50.6%, with methane selectivity of 77.5% was achieved on FeCoNiCu catalyst at 400°C. The best catalyst for the deep oxidation process was shown to be FeCoNiCuCr, on which the temperature of 100% CO conversion was 250°C and 100% conversion of propane was achieved at 450°C.