Exploring high-performance and cost-effective electrocatalysts that are applicable in oxygen evolution reaction (OER) is crucial for water splitting and energy storage. In this work, a facile and scalable chemical reduction strategy is developed to synthesize FeCoNiPB non-noble metal-based amorphous high-entropy oxides for the OER in alkaline media. The FeCoNiPB oxides exhibit overpotentials of 235 and 306 mV at current densities of 10 and 100 mA/cm², respectively, as well as a small Tafel slope of 53 mV/dec in 1.0 M KOH solution, outperforming the performance of FeCoPB, FeNiPB, and CoNiPB oxides and the commercial RuO₂, while maintaining excellent stability with negligible overpotential amplification over 40 h. The superior OER electrocatalytic efficiency and stability of the FeCoNiPB catalyst is primarily attributed to its unique amorphous high-entropy nanostructure, synergistic effect of the multiple components, and in situ-formed amorphous sheets with a thin (FeCoNi)OOH crystalline layer on the edge during long-term OER. This work provides new insights to design and prepare low-cost, highly efficient, and durable OER electrocatalysts.

Fe-based bulk metallic glasses (BMGs) have attracted great attention due to their unique magnetic and mechanical properties, but few applications have been materialized because of their brittleness at room temperature. Here we report a new Fe₅₀Ni₃₀P₁₃C₇ BMG which exhibits unprecedented compressive plasticity (>20%) at room temperature without final fracture. The mechanism of unprecedented plasticity for this new Fe-based BMG was also investigated. It was discovered that the ductile Fe₅₀Ni₃₀P₁₃C₇ BMG is composed of unique clusters mainly linked by less directional metal-metal bonds which are inclined to accommodate shear strain and absorbed energy in the front of crack tip. This conclusion was further verified by the X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy experiments of Fe_80-xNi_xP₁₃C₇ (x = 0, 10, 20, 30) and Fe_72-xNi_xB₂₀Si₄Nb₄ (x = 0, 7.2, 14.4, 21.6, 28.8) glassy systems. The results also indicate a strong correlation between the p-d hybridization and plasticity, verifying that the transition from brittle to ductile induced by Ni addition is due to the change of bonding characteristics in atomic configurations. Thus, we can design the plasticity of Fe-based BMGs and open up a new possible pathway for manufacturing BMGs with high strength and plasticity.

FePC amorphous ribbons using Fenton-like reactions are proved to show excellent degradation performance in wastewater treatment for the first time by decolorizing methylene blue (MB). Compared to the widely investigated FeSiB amorphous ribbons for decolorization, FePC alloys have higher degradation efficiency and lower reaction activation energy, which comes from the fast mass and electron transport due to the 3D nanoporous structures formed during the reaction, as well as the galvanic cells formed between the strong Fe–C and the weak Fe–P bonds. The observed unique “self-renewing” behaviour of FePC ribbons during cyclic tests explains their extremely long service life. The FePC amorphous ribbons are applicable in acidic MB solutions, but not in neutral or alkaline solutions. The highest degradation efficiency is achieved when the initial pH = 3 and the initial H₂O₂ concentration is 5 mM. The time required for the decomposition of MB drops with the increase of the ribbon dosage or the decrease of the initial MB concentration. This work not only provides a new highly efficient and low-cost solution for wastewater remediation, but also extends the application fields of FePC amorphous alloys.

Electrocatalytic hydrogen production plays an essential role in generating eco-friendly fuels for energy storage and transportation within a sustainable energy framework. High-entropy alloys (HEAs), with their abundant compositional variety, significantly expand the scope of material libraries and have received substantial research interest in energy and environmental technologies. However, the conventional approach to modulating HEA catalysts through element selection and exploiting the cocktail effect overlooks the potential of the high designability of high-entropy solid solutions. Herein, we present a novel strain engineering strategy to further enhance the catalytic performance of a desirable HEA composition by incorporating vacancy-induced microstrain into an HEA film. The strain engineered HEA film delivers an economically viable industrial water electrolysis capacity at an ampere-level current density of 1 A cm⁻² with overpotentials of 104 and 106 mV under alkaline and acidic conditions, respectively. Remarkably, it retains long-term sustainability of ∼500 h at 100 mA cm⁻² in an anion exchange membrane (AEM) device, demonstrating a lifespan 40 times that of a commercial Pt/C||IrO₂ system. Microstructural analyses and computational calculations indicate that the active sites with a low coordination environment enhance charge transferability, and thus promote the water adsorption capacity. Furthermore, the microstrain effect downshifts in the d-band center of Pt to a near-optimal position, which subsequently lowers the binding affinity between Pt and intermediates, resulting in enhanced hydrogen evolution reaction activity. Our work demonstrates a practical strain engineering strategy that provides a new avenue to enhance the performance of catalysts for sustainable energy conversion.