Biomorphic Porous Nickel-Based Multialloy Foils: Multi-metal Incorporation and Selenization-Driven Phase and Microstructure Evolution for Enhanced Methanol Electro-oxidation Catalysis

The development of nickel-based multi-alloy catalytic electrodes for methanol oxidation reactions (MOR) holds significant potential for advancing new energy technologies. The study fabricated a biomorphic Ni 6 MnFeCoCu multi-element porous alloy foil via filter paper template-assisted impregnation and carbonization–reduction. The effect of selenization treatment on the phase composition, microstructure, and MOR performance of Ni 6 MnFeCoCu has been investigated. The results showed that biomorphic nickel-based multialloy foils inherited the porous fibers structure of the filter paper template. The main phase of Ni 6 MnFeCoCu are a face-centered cubic multi-element metallic phase and MnO phase. With increasing selenization temperature, the large particles on the surface of the fiber struts gradually presented; Ni in Ni 6 MnFeCoCu preferentially form NiSe 2 with Se, followed by Cu and Fe, resulting in the formation of biphasic nickel selenide (NiSe 2 and Ni 3 Se 4 ), Cu 2− x Se, and Cu 0.41 Fe 0.60 Se 1.99 at 400 ℃. The locally controlled charge, attributed to the synergistic effect of multi-metals and the incorporation of Se, enabled the optimized Ni 6 MnFeCoCu-Se 350 catalytic electrode to exhibit high methanol oxidation reaction (MOR) catalytic activity and excellent cycling stability. Compared to the current density value (@ 0.8 V) of the porous Ni p , the values of the Ni 6 MnFeCoCu and optimized Ni 6 MnFeCoCu-Se 350 increased by 13.3% and 30.4% for methanol oxidation, respectively. After a chrono-current test of 10,800 s, the current density of the electrode was retained at 92.2% of its original values. These findings provide a strategic pathway for designing lightweight, efficient, and durable multi-metal catalytic electrodes for sustainable energy applications. Graphical