Excellent Oxidation Research Articles

Key coordination of oxygen doping in Fe single-atoms enhances nonradical activation of peroxymonosulfate: The formation of high-valent Fe species and electron transfer

Modulating the coordination environments and the electronic configurations of the metal centers of single-atom catalysts (SACs) to further improve the activation of peroxomonosulfate (PMS) remains a great challenge. In this work, oxygen (O) atoms were doped into Fe-N4 single-atom catalysts via oxygen-containing acid precursors to adjust the electronic structure to enhance PMS activation. The prepared Fe-N4O single-atom catalysts exhibited excellent oxidation capacity, tolerance, elevated stability and continuous organic oxidation. The primary degradation pathway is the high-valent iron (Fe IV = O) and the electron transfer mechanism. DFT calculations indicated that the adsorption energy and electron transfer number of second-shell-coordinated Fe-N4O were much higher than those of one-shell-coordinated Fe-N3O. The introduction of O atoms increased the electron density of the central Fe atoms and the electron delocalization domains, which increased the electron transfer capacity. This research provides a method to finely control the coordination environment and electronic structure of Fe-N4, revealing the unique dynamic regulation mechanism of heteroatoms for advanced oxidation, and providing a reference for the design of high-efficiency Fenton-like-based catalysts.

A novel seawater hydrothermal-deep eutectic solvent pretreatment enhances the production of fermentable sugars and tailored lignin nanospheres from Pinus massoniana

Lignocellulose biorefinery depended on effective pretreatment strategies is of great significance for solving the current global crisis of ecosystem and energy security. This study proposes a novel approach combining seawater hydrothermal pretreatment (SHP) and microwave-assisted deep eutectic solvent (MD) pretreatment to achieve an effective fractionation of Pinus massoniana into high value-added products. The results indicated that complex ions (Mg2+, Ca2+, and Cl−) in natural seawater served as Lewis acids and dramatically promoted the depolymerization of mannose and xylan into oligosaccharides with 40.17 % and 75.43 % yields, respectively. Subsequent MD treatment realized a rapid and effective lignin fractionation (~90 %) while retaining cellulose. As a result, the integrated pretreatment yielded ~85 % of enzymatic glucose, indicating an eightfold increase compared with untreated pine. Because of the increased hydrophobicity induced by the formation of acyl groups during MD treatment, uniform lignin nanospheres were successfully recovered from the DES. It exhibited low dispersibility (PDI = 2.23), small molecular weight (1889 g/mol), and excellent oxidation resistance (RSI = 5.94), demonstrating promising applications in functional materials. The mechanism of lignin depolymerization was comprehensively elucidated via FTIR, 2D-HSQC NMR, and GPC analyses. Overall, this study provides a novel and environmentally friendly strategy for lignocellulose biorefinery and lignin valorization.

Effective degradation of organic pollutants by CuFe@C composite derived from bimetallic MOFs synthesized through stepwise feeding method

In this work, Cu-Fe bimetal-embedded carbonaceous CuFe@C materials were prepared by high-temperature pyrolysis of CuFe-MOFs precursors synthesized through a facile two-step feeding approach. Through adjusting the reaction time of each feeding step, CuFe-MOFs of uniform dispersed crystals with controlled sizes were obtained. The carbonized composites were then applied to activate persulfate (PMS) for Reactive Brilliant Red X-3B (RBRX-3B) degradation in water. The removal rate of RBRX-3B was up to 98% in 40 min in the CuFe@C600/PMS system, indicating that the CuFe@C600 catalyst showed excellent sulfate radical-based oxidation (SR-AO) activity in the degradation process. The effects of PMS dosage, initial pH, RBRX-3B concentration on the degradation efficiency were investigated in detail. Based on quenching experiments, a possible mechanism for the CuFe@C600/PMS system was proposed. The catalyst had good reusability, in which the removal rate of RBRX-3B could attain 82% after 5 times of repeated recycling. It also showed satisfactory removal effect on other organic pollutants, i.e. Congo red, Methyl orange, Reactive blue and p-nitrophenol. This study provided a valuable strategy for the treatment of wastewater containing organic pollutants using MOFs-derived materials.

Fabrication of mechanically alloyed high entropy alloys (20-Fe-20Cr-20Ni-20Mn-20Ti) modified carbon paste electrode sensor for the cyclic voltammetric determination of methyl orange

We have successfully fabricated high entropy alloys (HEA) of composition 20-Fe-20Cr-20Ni-20Mn-20Ti by ball milling method for 20 h after optimizing the milling parameters. Generally, the HEAs are very popular for their multi-elemental cocktail effect and exhibit excellent high temperature oxidation resistance, high strength, electromagnetic, wear and corrosion resistance properties. But, HEAs also exhibit significant electrocatalytic properties due to their unique morphology, composition, and structure. Therefore, we have used planetary ball milled HEA powders for the electrochemical determination of methyl orange (MO). MO is recalcitrant and very difficult to degrade and can affect the humans as well as the environment. Therefore, we must determine the presence of MO. We have investigated the effect of scan rate, modifier and analyte concentration, and the pH variation on the anodic peak current (Ipa) of MO. The calculated active syrface area of bare carbon paste electrode (BCPE) and HEA-modified carbon paste electrode (HEA-MCPE) were found to be 0.041 cm2 and 0.137 cm2 respectively. We have obtained the maximum oxidation peak current for the 8 mg HEA-MCPE at a pH of 7.2 during the electrochemical oxidation of MO. The increased Ipa in basic medium is due to structural transformation of MO from quinoid form (in acidic medium) to azo structure (in basic medium). We have also calculated the number of electrons and the protons involved in the electrochemical reaction. The calculated values of detection limit (DL) and quantification limit (QL) of 8 mg HEA-MCPE was found to be 0.114 × 10−8 M and 0.38 × 10−8 M respectively.

Excellent oxidation resistance of rapidly crystallizing Cr2AlC coatings at high temperatures: Effect of microstructure

Two kinds of Cr2AlC coatings with different microstructures were prepared by direct crystallization during oxidation at 1000 ℃ and conventional crystallization at 700 ℃ for 1 h for amorphous Cr-Al-C coatings prepared by magnetron sputtering, respectively. The effect of microstructure on the oxidation behavior of the coatings at 1000 ℃ was investigated. The grain boundary density and dislocation density of the Cr2AlC coatings crystallized directly during oxidation were much higher, which provided much more sites for heterogeneous nucleation of α-Al2O3 and fast diffusion paths for Al. Therefore, the coating formed complete pure α-Al2O3 scales earlier with better antioxidant properties. More importantly, the present work demonstrates feasibility and advantages of directly applying amorphous Cr-Al-C coatings at high temperatures without additional crystallization treatments, which simplifies preparation process of Cr2AlC coatings, facilitates their industrial applications, and provides a new method for rapid preparation of MAX-phase coatings.

High temperature oxidation behaviors of TaCrTiW and TaCrTiZrW alloy coatings

The high-temperature oxidation behaviors of a series of refractory high entropy alloys TaCrTiW and TaCrTiZrW alloy coatings at 1073 K in air were studied. A complex protective oxide layer consisting of Cr2O3, TiO2, and CrTaO4 oxides was generated on the alloys surface. Among the TaCrTiW alloy coatings, the presence of TiO2 inhibited the generation of unfavorable oxides and promoted the generation of CrTaO4. The Ta41.7Cr50.3Ti4.5Zr1.6W1.9 exhibits excellent oxidation resistance. The addition of Zr not only accelerated the initial oxide formation but also promoted the rapid formation of Cr2O3.

SnO2-modified CuMnOx catalysts for humid CO oxidation at low temperature

Low-temperature CO oxidation has been widely applied in environmental pollution control, but challenges remain in CO purification in high-humidity environments. In this study, the CuMnSn8 catalyst exhibited excellent low-temperature CO oxidation performance, achieving complete CO oxidation at temperatures below 55 °C in 85 % relative humidity. A series of characterizations indicated that an appropriate amount of SnO2 doping could promote the formation of more amorphous oxides, increase the oxygen species content, and facilitate the dispersion of Cu and Mn elements. The catalytic active sites for CO oxidation and the influence of SnO2 doping on the CO oxidation mechanism were investigated through in-situ DRIFTS experiments. The results indicated that Sn enhanced the synergistic effect between Cu and Mn, altered the pathway of CO oxidation reaction, generated more easily decomposable bidentate carbonate intermediates. This work provides insight into the design of CO oxidation catalysts with high activity in high humidity.

Observation of the formation of CuAl2O4 by the direct consumption of Al2O3 in an NAB alloy at elevated temperature

The oxidation behaviors of a commercial C95500 nickel aluminum bronze (NAB) alloy at elevated temperatures were investigated. The oxide scale exhibited a triplex structure with an outmost CuAl2O4 layer, an intermediate spinel-type Al2O3 layer, and a deepest nano Al2O3 film. The observation of CuAl2O4 and Al2O3 in the same grain with the same crystallographic orientation indicated that the outmost CuAl2O4 was formed by directly consuming the spinel-type Al2O3. Such a transformation process can avoid the formation of defects in the oxide scale caused by the transformation between different Al2O3 variants, attributing to the origin of the excellent oxidation resistance.

Microstructure development of plasma sprayed dual-phase high entropy ceramic coating derived from spray dried and induction plasma spheroidized powder

Dual phase high entropy ceramics (DPHECs) exhibit excellent high temperature mechanical properties and oxidation resistance. Nevertheless, they cannot be applied in the structural components on large scale due to their intrinsic brittleness. Hence, DPHEC coating is a necessary development direction for industrial applications. In this study, we first fabricated micron-order DPHEC powder with high quality by precursor synthesis, spray drying (SD), and induction plasma spheroidization (IPS). The DPHEC coating was prepared by supersonic atmospheric plasma spraying (SAPS). The microstructure, phase compositions, and mechanical properties of the DPHEC powder and coating are investigated in detail. Results show that the SD&IPS powder and SAPS coating are all composed of HEB and HEC phases, showing slight composition segregation and typical global eutectic microstructure. The nanohardness and Young's modulus are 22.17 ± 2.76 GPa and 309.79 ± 35.71 GPa, respectively. The fracture toughness was calculated to be 2.23 ± 0.17 MPa m1/2 from the energy analysis method. The mechanical properties are enhanced by the solid solution and fine grain strengthening effects and are weakened by the intrinsic defects of plasma sprayed coating. This work provides a new method and a potential material for thermal spraying ultra-high temperature ceramic coatings.

Impact of molten salts composition on the corrosion behavior of NiMoCr and CoNiCrAl coatings on L-PBF 316L stainless steel for CSP plants

The high-temperature corrosion performance of NiMoCr and CoNiCrAl coatings produced by high velocity oxy-fuel (HVOF) on laser powder bed fusion (L-PBF) 316L stainless steel substate has been evaluated in presence of three different molten salts used as thermal energy storage (TES) materials for concentrated solar power (CSP) plants. The coatings have an excellent oxidation resistance at 700 °C, showing a percentage of affected thickness lower than 2 %, due to the formation of a protective layer of Cr2O3 and Al2O3 in both NiMoCr and CoNiCrAl coatings, respectively. The carbonates-based molten salt accelerates the corrosion of the NiMoCr coating, affecting around 43 % of the coating thickness, due to the formation of chromates and the high depletion of Mo in the coating. In contrast, the effective protection shown by the CoNiCrAl coating is explained because the grown LiAlO2 after the lithiation process has a high capacity to act as a strong diffusion barrier for metal ions and inhibited the formation of chromates. In the presence of two different ZnCl2 and MgCl2-rich molten salts, the CoNiCrAl coating behaved worse than NiMoCr coating due to the breakage of the (Al,Cr)-rich oxide layer as a consequence of an active oxidation mechanism and due to the formation of voids along the entire thickness, which were identified in 100 % of the coating thickness. The superior corrosion resistance of the NiMoCr coating in presence of the chloride rich molten salts was attributed to the presence of Mo, which fixed the Cr and inhibited the diffusion of oxygen.

Li6.28La3Zr2Al0.24O12-reinforced Single-ion Conducting Composite Polymer Electrolyte for Room-Temperature Li-Metal Batteries

Composite polymer electrolytes composed of inorganic fillers and organic polymers are promising electrolyte candidates for Li metal batteries, with benefits of improved safety and suppressed lithium dendrite growth. However, a severe concentration polarization effect often occurs when using conventional dual-ion electrolytes, and the increase in internal impedance during cycling results in decreased lifespan of the battery. To address this challenge, a plasticized single-ion conducting composite polymer electrolyte (SICE) was designed and fabricated by polymerizing the monomers of lithium (4-styrenesulfonyl) (trifluoromethanesulfonyl) imide (LiSTFSI) and poly(ethylene glycol) methyl ether acrylate (PEGMEA), crosslinker poly(ethylene glycol) diacrylate (PEGDA), silane-modified Li6.28La3Al0.24Zr2O12 nanofibers (s@LLAZO NFs), along with a PEG-based plasticizer tetraethylene glycol dimethyl ether (TEGDME), by heat-initiation. The anions were restrained and delocalized so that only Li cation migration occurred during the charging/discharging process, leading to a superior lithium-ion transference number. The s@LLAZO NFs enabled direct monomer grafting with the polymer matrix, resulting in controlled formation of an organic-inorganic network with increased filler content and improved filler distribution in the SICE system. The SICE membrane exhibited high ionic conductivity at room temperature, reduced activation energy and excellent oxidation stability. Most importantly, the all-solid-state Li-metal batteries assembled with the fabricated SICE demonstrated stable long-term cycling performance and remarkable rate capability at room temperature.

A review on mechanical alloying and spark plasma sintering of refractory high-entropy alloys: Challenges, microstructures, and mechanical behavior

Refractory high-entropy alloys (RHEAs) are promising candidates for those applications requiring of strong materials at high temperatures with elevated thermal stability and excellent oxidation, irradiation, and corrosion resistance. Particularly, RHEAs synthesized using mechanical alloying (MA) followed by spark plasma sintering (SPS) has proven to be a successful path to produce stronger alloys than those produced by casting techniques. This superior behavior, at both room and high temperature, can be attributed to the microstructural features resultant from this powder metallurgy route, that include the presence of homogeneously distributed non-metallic particles, fine- and ultrafine-grained microstructures, and higher content of interstitial solutes. Nevertheless, the powder metallurgy fabrication relies over a complex balance of several operational variables, and the process is no exempt of certain challenges, such as contamination or the presence of pores in the bulk parts. This review aims to cover all the peculiarities of the MA + SPS route, the resultant microstructures, their mechanical properties, and the strengthening and deformation mechanisms behind their superior performance, as well as a brief description of their oxidation resistance.

High temperature tribological properties of TiAlSiN/NiCr multilayer coatings with different modulation periods

In this work, TiAlSiN/NiCr multilayer coatings with different modulation periods were deposited by cathodic-arc techniques, which combined filtered cathode vacuum arc (FCVA) and cathodic-arc ion plating (CAIP) techniques to deposit sublayers at different bias voltages. The nanoscale multilayer coating (TiAlSiN: 88 nm; NiCr: 9 nm) exhibited excellent oxidation resistance and thermal stability. Annealed coatings at 900 °C in air for 1 h, the thickness of the oxide layer of N32 coating is only 0.91 μm and the increase in coating thickness was only 9.01%, while the thickness of oxide layer of monolayer TiAlSiN coating is 3.02 μm and thickness increasing of 122.28%. Due to the existence of numerous interfaces, the N32 coating exhibited the lowest wear rate of 1.92 × 10−7 mm3N−1m−1 at 600 °C under abrasive wear and adhesive wear mechanisms. In parallel, a new AlNi intermetallic compound with excellent thermal stability was characterized by high-resolution transmission electron microscopy (HRTEM) at the coating interfaces. This compound is derived from different cathodic-arc techniques and bias voltages used to deposit coatings, which provides a reference for the structural design of coatings facing thermal environments.

BRIEF OVERVIEW OF METHODS FOR PRODUCING TiSiCN COATINGS AND THE METHOD OF REACTIVE PLASMA SPRAYING

Modern materials science sets itself the task of developing new materials with multifunctional coatings. Materials with such coatings are widely used in various fields of technology: construction and energy, microelectronics, aviation and others. The main reason for the emergence and development of technology for applying multifunctional protective coatings is the desire to increase the durability of parts and assemblies of various machine mechanisms. Wear-resistant hard coatings based on transition metal nitrides and carbonitrides are widely used to extend the life of forging and extrusion dies and high-speed machining tools. Over the past two decades, the widespread use of these coatings has stimulated and supported the development of new processes and materials in an attempt to further improve their properties. Among these coatings, the higher hardness, excellent oxidation resistance and high thermal stability of coatings such as TiSiN and TiSiCN make them the most promising candidates for demanding tribological applications. In addition, TiSiCN coating is a promising material used in marine environments due to its excellent anti-wear and corrosion resistance, as well as high hardness and low friction coefficient. These combinations of properties make TiSiCN coatings potential candidates for protective layers in the automotive and petroleum industries.The article briefly examines the possibilities of producing TiSiCN coatings using different deposition methods to control the properties of the resulting films and the features of the reactive plasma spraying method. The work describes the most common methods and technologies for producing carbonitride coatings currently used. The latest developments and current trends in the field of plasma spray coating technologies are reviewed, taking into account important innovations for industrial coatings. New conclusions that were obtained as a result of fundamental and applied research in physics or chemistry are based on them. The article provides a comparative review of the characteristics of obtaining wear-resistant TiSiCN coatings and the features of using reactive plasma spraying to obtain wear-resistant coatings. Based on an analysis of the literature, it can be argued that the further development of reactive plasma technology is associated with the development of a new resource-saving method for the formation of composite coatings with increased corrosion and tribological characteristics, which corresponds to the development trends of world science.

Compatibility and effect of capacity ratios between Na3V2(PO4)3 and hard carbon in highly concentrated sodium bis (fluorosulfonyl) imide electrolyte

From the standpoint of preserving the Earth's resources and ensuring the long-term viability of humanity, it is imperative to transition away from lithium-ion batteries. High-performance and safe sodium-ion batteries have recently emerged as promising advanced batteries for application in stationary energy storage, attributed to their low cost and abundance of sodium ion. We demonstrate the compatibility and effect of the negative-positive capacity ratio in full-cell Na3V2(PO4)3 and hard carbon in high-concentration electrolytes. Thanks to the excellent oxidation stability of the electrolyte, during 100 cycles, the full cell with a negative-positive capacity ratio of 1.1 demonstrated a consistent capacity of around 100 mAh g-1 with a capacity retention of 90.7%, whereas the full cell with a ratio of 1.0 showed a steady discharge capacity of roughly 90 mAh g-1 with a capacity retention of approaching 100% at a current density of C/5.

Double-hindered phenolic SiO2 composites with excellent oxidation resistance and thermal stability for enhanced thermal oxidation stability of PPS

In recent years, loading antioxidants onto inorganic nanoparticles has attracted increasing interest. However, the existing studies not only have low antioxidant loading efficiency, but also ignore the relationship between structural changes and antioxidant properties before and after antioxidant modification, greatly limiting the improvement of the antioxidant properties of composites and their application scope. In this work, we successfully prepared bis-hindered phenolic antioxidants containing silica hydroxyl groups (Bis-mAO) and loaded them onto silicon dioxide (SiO2) to get the nanocomposites (Bis-mAO-SiO2). The melt blending method further prepared the corresponding polyphenylene sulfide (PPS)/Bis-mAO-SiO2 composites. The results showed that the higher antioxidant loading and more suitable antioxidant structure made Bis-mAO-SiO2 possess excellent antioxidant properties. The prepared PPS/Bis-mAO-SiO2 composites remained stable under high temperatures and oxygen environments. Impressively, the maximum weight loss rate temperature of PPS/Bis-mAO-SiO2 was increased by 11.60 °C compared to that of PPS, and after accelerated thermal oxidation at 220 °C for 24 h, the relative intensity ratio between O and C of PPS/Bis-mAO-SiO2 only increased to 0.086, much lower than 0.132 for PPS. Moreover, the viscosity of PPS/Bis-mAO-SiO2 only increased by 29.05 % and 88.75 % after accelerated thermal oxidation at 220 °C for 12, 24 h. Compared, PPS's viscosity increased substantially by 79.22 % and 250.3 %, respectively. This meant that the Bis-mAO-SiO2 successfully achieved a synergistic integration of high antioxidant properties and thermal stability, implying that the work offered a strategy for fabricating high-temperature resistant antioxidant composites.

Toward understanding the damage behavior during orthogonal cutting of 2.5D C/SiC composite based on multi-scale modeling and high-speed photography

2.5D C/SiC composite has been a critical high temperature material for aerospace filed due to its excellent wear, high temperature and oxidation resistance. Understanding the cutting damage behavior is crucial for achieving the high reliability application. This paper presents an in-depth study on damage behavior and material removal mechanism during orthogonal cutting of 2.5D C/SiC composite based on multi-scale modeling and high-speed photography. A three-dimensional numerical micro-macro multi-scale model is established considering the characteristics of the brittle SiC matrix, the isotropic carbon fiber reinforcement, and the pyrolytic carbon (PyC) layer. The orthogonal cutting experiments of 2.5D C/SiC composite with high-speed photography technology is carried out. The results show that the proposed model can accurately predict the microscopic deformation and fracture of the fiber. Meanwhile, surface fiber spring-back phenomenon is found based on high-speed photography, and its mechanism is first explanation based on the stress evolution analysis of the multi-scale model. In addition, it indicates that the increase of the depth of cut has a significant impact on the chip shape evolution, transitioning from powdery, needle-like, to block-like or strip-like shape. The paper covers some new sights for low-damage cutting of 2.5D C/SiC composite materials.

Fire-resistant and thermal insulation performance of SiC nanofiber batt fabricated from cotton fiber batt

The cotton fiber batt is one of the most commonly used thermal insulator in our lives at room temperature because of its flexible and porous structure. The SiC nanofibers have excellent mechanical, physical, and chemical properties such as high mechanical strength and modulus, low density, high-temperature resistance, which is a promising material for high temperature structural materials or thermal insulator. In this work, a flexible SiC nanofiber batt was fabricated from the cotton fiber batt by sol-gel carbothermal reduction reaction. The fluffy carbonized porous cotton batt was used as a template for the fabrication of sponge-liked SiC nanofiber batt composed of single crystalline β-SiC fibers. It exhibits good compressive flexibility, ultra-high porosity (a specific surface area was 30.90 m²/g), excellent high-temperature stability (ranging from −196 °C in liquid nitrogen to 1300 °C under the flame of butane blowtorch) and low thermal conductivity (0.02 W/(m·K) at room temperature). The SiC nanofiber batt, which has low density, excellent high-temperature resistance and oxidation resistance, is a promising material for high-temperature structural materials or thermal insulators under extreme conditions. The facile fabrication method of SiC nanofiber batt from common cotton batt provides a novel technique for economic industrial production of high temperature thermal insulation material.

Ultrathin amorphous NaIrRuOx nanosheets with rich oxygen vacancies for efficient acidic water oxidation

Developing highly active and durable catalysts for H2O/O2 conversion is particularly important in water electrolyzers for renewable hydrogen energy. Herein, we prepared ultrathin amorphous NaIrRuOx nanosheets (NSs) with a thickness of 1.2 nm with a large number of oxygen vacancies using a simple molten salt method. The NaIrRuOx NSs exhibits a low overpotential (η10, 10 mA cm−2) of 214 mV, and 8.6 and 45.7 times enhanced mass activitynoble metal at 1.53 V vs. RHE, as compared to the commercial RuO2 and IrO2, respectively. Furthermore, the NaIrRuOx NSs shows excellent corrosion and oxidation resistance in acidic oxygen evolution reaction (OER), as confirmed by a negligible potential increase after 100 h of continuous electrolysis. In a homemade PEMWE, a membrane electrode using NaIrRuOx NSs as the anode catalyst can achieve cell voltages of 1.74 V at 1 A cm−2 and operate stably at 1 A cm−2 for 350 h. Theoretical calculations indicated that the intercalation of Na+ into IrRuOx weakens the adsorption strength of OER intermediates, thus reducing the energy consumption in the conversion from O* to OOH*, and thus significantly improving the OER performance.

High temperature oxidation behavior of CoCrFeNiMo0.2 high-entropy alloy coatings produced by laser cladding

The oxidation behavior of CoCrFeNiMo0.2 high-entropy alloy laser cladding coatings at 700°C and 900°C was investigated. The oxidation kinetics of the alloys at all temperatures followed a parabolic behavior, with the oxidation rates increasing significantly with increasing temperature. The alloy exhibits excellent oxidation resistance at 700 °C. Compared with the original alloy structure, the segregation of Mo element in the alloy is more serious after high-temperature treatment. Compared with 700 °C, the oxidation degree of the alloy is more intense at 900 °C. The reaction between iron and chromium oxides forms a chromite layer, and the rapid diffusion of iron ions in the layer forms an outer layer of iron oxides. As the oxidation proceeds, the oxide film is separated from the metal, and the chromium oxide layer grows between the spinel layer and the metal. The thermodynamics of the reaction was calculated, the oxidation mechanism of the alloy was explored, and a high-temperature model of the alloy was developed. This study expands the potential applications of high entropy alloys in surface engineering.