Amorphous Composition Research Articles

A review of the preparation and prospects of amorphous alloys by mechanical alloying

The preparation of amorphous alloys typically involves rapid solidification from a molten state. Since 1980, when Yermo and Koch first achieved the amorphization of alloys by mechanical alloying (MA), researchers worldwide have developed a strong interest in this technique, which allows for the amorphization of alloy components in a non-equilibrium state at room temperature without the need for a liquid phase. MA has been widely applied in the fabrication of both equilibrium and non-equilibrium materials over the past few decades, and it remains a crucial technique for the production of amorphous alloys. This review selectively summarizes research on MA-produced amorphous alloys reported over the past two decades. It explores key issues of MA amorphization from the perspectives of both the mechanism of amorphization and the design of amorphous compositions through MA. The first section primarily elucidates commonly used methods for designing amorphous compositions at present, while the second section expounds on the transformation mechanism of MA amorphization. The third section summarizes the influence of alloy element additions on its properties, and the fourth section mainly illustrates the contribution of computational advancements to the exploration of amorphous mechanisms and the design of amorphous compositions. Finally, prospects for the development trend of preparing amorphous alloys through MA are discussed.

Material screening for future diffusion barriers in Cu interconnects: Modeling of binary and ternary metal alloys and detailed analysis of their barrier performance

One of the challenges in the semiconductor industry is to find new barrier materials and copper (Cu) alternative solutions in interconnects. In this work, we focused to find alternative diffusion barrier materials. Different binary (CoMo, CoRu, CoTa, CoW, MoRu, RuTa, RuW) and ternary (CoMoTa, CoRuTa, MoRuTa) metal alloys were evaluated theoretically with the Miedema model to find the amorphous phase composition range. Afterward, thin films of the alloys with various compositions were deposited by magnetron sputtering and theoretical values were compared to the experimental results. From the experimental measurements, which included grazing incidence x-ray diffraction analysis and resistivity measurements, suitable binary and ternary alloys were chosen for diffusion analysis. By annealing thin film stacks at temperatures ranging from 500 to 675°C, diffusion was induced and detected by x-ray photoelectron spectroscopy depth profiles. Seventeen alloys were evaluated by their diffusion barrier effectiveness, and five of those, which include Ru60Ta40, Ru45W55, Mo47Ru53, Mo36Ru50Ta14, and Co40Mo35Ta25, showed excellent barrier properties against copper diffusion. Furthermore, all of the stated materials have a lower resistivity than TaN. Last, the adhesion of the best performing alloys to SiCOH and Cu was evaluated by the modified edge lift-off test. Only Ru45W55 had reasonable adhesion at both interfaces. The other materials showed low adhesion strength to Cu, which would make an adhesion promoter (liner), such as cobalt, necessary for the integration.

Influence of porosity on the Umov effect in silicate and organic refractory aggregates

This study investigates the influence of porosity on the Umov effect, a phenomenon observed in the scattering of light from celestial objects. The Umov effect describes an inverse relationship between the degree of linear polarization and the object’s reflectance (geometric albedo). To study the dependence of porosity on the Umov effect, a wide range of porosity (i.e., from 0.64 to 0.99) is considered. Four types of aggregates, ballistic cluster–cluster aggregate (BCCA), ballistic particle cluster aggregate (BPCA) or ballistic agglomeration (BA), ballistic agglomeration with one migration (BAM1), and ballistic agglomeration with two migrations (BAM2) each having porosity 0.99, 0.87, 0.74, and 0.64 are considered in this study. The multi-sphere T-matrix code is utilized to calculate the linear polarization and geometric albedo (A) considering silicate and organic refractory compositions for monodisperse aggregates. The results are reported for six different wavelengths, ranging from near-ultraviolet to the visible spectrum. When the polarization maximum (Pmax) is plotted against the geometric albedo (A) on a logarithmic scale, an inverse relation is observed. This relation exhibits non-linear changes, fitted by a second-degree polynomial equation, as the porosity changes from 0.64 to 0.99. This finding constitutes one of the interesting results of our study. In addition, the study explores the effect of porosity (P) on the ratio between log(Pmax) and log(A), showing a non-linear relationship. A comparison is drawn between the results obtained from organic refractory compositions and amorphous silicate compositions, emphasizing the importance of porosity and wavelength in regulating the Umov effect. In addition, the research investigates how mixing affects the results at different wavelengths, assuming the aggregates are blends of organic refractory and amorphous silicate compositions. The computations have also been performed for polydisperse aggregates (considering BCCA, BA, BAM1, and BAM2 structures) at a wavelength of 0.45 μm for silicate compositions, which also showed a non-linear dependence as observed in the case of monodisperse aggregates.

Novel nano-thin amorphous Ta-coating on 3D-printed porous TC4 implant: Microstructure and enhanced biological effects

Bone defects caused by tumors, trauma, or other bone diseases are common in clinical practice. Titanium alloy (TC4) and tantalum (Ta) are the primary metallic materials for bone repair. However, TC4 frequently suffers from poor osseointegration and implant loosening, while the high cost of Ta limits its widespread use for reconstructing large bone defects. To address this issue, this research employs magnetron sputtering (MSP) to deposit a nano-thin amorphous Ta-coating on the 3D-printed TC4 implant. SEM examinations of compressed samples show robust interfacial bonding without shedding, while the presence of Ta within the porous structure indicates high coverage. High-resolution TEM analysis first reveals a distinct multilayer amorphous zone consisting of surface TaOx, Ta-coating, and hybrid TaOx and TiOx, along with an impact-refinement nanocrystalline TC4 zone. Insufficient energy leads to the formation of amorphous layers. Meanwhile, interfacial bonding is strengthened through the solid solution of oxygen and interfacial densification of amorphous-crystalline bonding and impact compression. Biological evaluations demonstrate that the Ta-coating exhibits superior cell proliferation and bone ingrowth effects compared to TC4 and pure Ta implants, primarily attributed to the amorphous oxide composition on the surface. This study offers novel, cost-efficient, and excellent biological performance materials for bone defect implants.

Fe‐Based Amorphous Alloy Coatings: A Review

Fe‐based amorphous alloy coatings (Fe‐AACs) have exhibited appropriate corrosion and wear resistance and improved the performance of material surfaces. This study summarizes the advances related to Fe‐based amorphous alloys pertaining to their chemical compositions and manufacturing processes and their associated effect on the amorphous structure, microstructure, and properties. In particular, Fe‐based amorphous alloy coatings produced by laser cladding are investigated to study the effect of amorphous structure, partial crystallization, and composition on the microstructure, hardness, corrosion, and wear resistance of these coatings. In addition, the effects of laser parameters (power and scanning speed) on the geometric and metallurgical characteristics of produced amorphous coatings are also covered.

Microstructure and thermal stability of crystalline/amorphous Fe/FeW nanomultilayers

The thermal stability of crystalline-amorphous interfaces was investigated in Fe/FeW nanomultilayers (NMs), where the alloy layers were amorphous in the as-sputtered state with concentrations of Fe-38 at.% W or Fe-67 at.% W. Compositionally driven devitrification, layer breakdown, and recrystallization were compared using both single-layer and multilayer configurations at temperatures ranging from 250 °C to 750 °C. Annealing of the NMs to 500 °C revealed destabilization in the Fe-67 W layers with the formation of crystalline-crystalline interfaces (CCIs) whereas the Fe-38 W layers remained intact with stable crystalline-amorphous interfaces (CAIs). Further annealing to 750 °C resulted in multilayer evolution and recrystallization, where breakdown of the CAIs was attributed to layer intermixing while the CCIs experienced intermetallic grooving and pinch-off. The influence of amorphous stability, composition, and intermetallic formation are discussed with respect to the NM breakdown mechanisms. This work highlights a promising strategy for exploring compositionally driven stability at the nanoscale in crystalline-amorphous alloys.

Design of Amorphous Alloy Composition and Optimization of Vacuum Die Casting Process Parameters Based on Co-evolutionary Algorithm

Design of Amorphous Alloy Composition and Optimization of Vacuum Die Casting Process Parameters Based on Co-evolutionary Algorithm

Optical red shift spectra in CuxGe32S68-x films for infrared and solar cell window applications

The physical characteristics of Cu-doped ternary glasses have been analyzed. The CuxGe32S68 − x (x = 0.0, 4.0, 7.0, 10.0 and 13.0 at.%) chalcogenide alloys have been manufactured by the conventional melt quenching method. The glass densities (ρ) increase with the Cu amounts, whereas the main atomic volume (Vm) decreases. Transmission and reflectance were measured in the wavelength range of 0.35–2.5 μm. The generated envelops (RM and Rm) of reflectance spectra were used to calculate the film thickness (t), the refractive index (n), and the extinction coefficient (k). With the increase in Cu contents from 0.0 to 13.0 at.%., the n values increased from 2.07 to 2.43, whereas the optical gap (Eg) decreased from 2.81 eV to 2.42 eV. The obtained results were explained in terms of electronic polarizability, plasma frequency, metallization parameter, and refraction losses, which have been calculated to understand the need for amorphous chalcogenide compositions that can be applied for optical device purposes. The effect of Cu content on the non-linear index of refraction (n2) and third-order susceptibility (χ (3)) has been studied. The value of n2 increased from 13.88 × 10−12 to 60.2 × 10−12 esu, whereas the value of χ (3) rose from 7.6 × 10−11 to 38.83 × 10−13 esu with the addition of denser and higher atomic radius elements Cu in the CGS system. Overall, the composition of Cu13Ge32S55 is suitable, as all-optical parameters show the maximum values that can be used for optical device purposes.

Regulation of static and dynamic magnetic properties of amorphous FeCoZr composition gradient films by Zr doping

A series of amorphous FeCoZr composition gradient monolayer films with varying Zr contents was prepared on the Si(100) substrate using RF magnetron sputtering. The effects of the Zr sputtering power PZr on the static and dynamic magnetic properties of FeCoZr films were systematically investigated. The results demonstrate that the introduction of the Zr element as a composition gradient into FeCo films not only improves the soft magnetic properties of the films but also enhances their in-plane uniaxial magnetic anisotropy. In particular, the doping of Zr elements leads to the destruction of FeCo lattice, inducing a transformation of the films from polycrystalline to amorphous state, resulting in a significant decrease in coercivity (Hc reduced by 82%) and surface roughness (Ra reduced by 78%). In addition, as PZr increases from 30 to 70 W, the anisotropy fields Hk of the films increase from 128 to 340 Oe, and the resonance frequency fr increases from 4.24 to 5.23 GHz. By fitting the permeability spectrum using the LLG equation, it is found that FeCoZr composition gradient films exhibit a lower damping coefficient α of around 0.011–0.014, indicating the reduction of energy loss during magnetization dynamics. These findings highlight the potential applications of FeCoZr composition gradient films in the field of high-frequency microwaves.

Tribological properties of laser-cladded Fe-based amorphous composite coatings under dry and lubricated sliding

Fe-based amorphous composite coatings are promising surface coating materials, because of their low cost, high hardness, and superior wear resistance. In the present study, Fe-based composite coatings with various amorphous contents (35.9–59.3%) were deposited onto 1045 steel via laser cladding, and the influence of laser-cladding parameters on the amorphous content was analysed. The cross sections of the coating layer and ground coating surface were then characterised in terms of the microstructure, phase composition, amorphous content, grain size, and microhardness. Importantly, the tribological properties of coatings with various amorphous contents under both dry and lubricated sliding conditions with light and heavy loads were systematically investigated. The microstructure of the crystalline/amorphous mixture was found to be a function of the temperature gradient, cooling rate, and chemical composition. The high microhardness was related to the amorphous content and grain size. The tribological properties were found to be insensitive to the amorphous content under both dry and lubricated conditions under light and heavy loads. The manifold morphologies of the wear tracks and the transition of the wear mechanism were the result of the combined effects of the amorphous content, phase composition, and size and distribution of the crystalline phase.

Modulating Barrier Properties of Stereocomplex Polylactide: The Polymorphism Mechanism and Its Relationship with Rigid Amorphous Fraction.

The barrier properties of semicrystalline polymers are crucial for their performance and their use as packaging materials. This work uncovers the mechanism of polymorphism modification (α, α' and stereocomplex-crystals) and its combined effect on the oxygen and water vapor barrier properties of semicrystalline stereocomplex polylactide (SCPLA). A polymorphic selective filler-type nucleator was employed to eliminate the temperature effect on the development of polymorphism and rigid amorphous fraction (RAF), allowing correlations of barrier properties with different crystal forms and RAF combinations under the same amorphous composition (SCPLA). The oxygen and water vapor barrier performances strongly correlated with crystallinity and crystal form but were not monotonically related to the RAF quantity. The study proposes that the chain conformation of intermediate phases between the crystalline and amorphous phases differs with the associated crystal forms, thereby leading to different RAF "qualities" and contributing to different gas diffusion and solubility coefficients of the amorphous regions. RAF's per unit excess free volume may be varied with crystal forms, for instance: α' ≫ SC > α. Therefore, SCPLA with α' crystals exhibited high oxygen and water vapor permeabilities. Those with high SC and α crystals showed similar barrier behaviors governed by Henry's law dissolution and followed a linear "two-phase" relationship with total crystallinity.

Inelastic relaxation processes in amorphous sodium silicates

AbstractDuring fracture amorphous oxides exhibit irreversible processes, including inelastic and nonrecoverable relaxation effects in the process zone surrounding the crack tip. Here, classical molecular dynamics simulations were used with a reactive forcefield to evaluate inelastic relaxation processes in five amorphous sodium silicate compositions. Overall, the 20% Na2O‐SiO2(NS20) composition exhibited the most inelastic relaxation, followed by the 15% Na2O‐SiO2(NS15) composition, the 25% Na2O‐SiO2(NS25) composition, and finally the 10% (NS10) and 30% (NS30) Na2O‐SiO2 compositions. Coordination analysis of the Na+ ions identified that during inelastic relaxation the Na+ ions were increasingly coordinated by nonbridging oxygens (NBOs) for the NS10 and NS15 compositions, which was supported by radial analysis of the O‐Na‐O bond angles surrounding the crack tip. Across the sodium silicate compositional range, two different inelastic relaxation mechanism were identified based on the amount of bridging oxygens (BOs) and NBOs in the Na+ ion coordination shell. At lower (NS10) and higher (NS30) sodium compositions, the entire structured relaxed toward the crack tip. In contrast at intermediate sodium concentrations (NS20) the Na+ ion migrates toward the crack tip separately from the network structure. By developing a fundamental understanding of how modified silica systems respond to static stress fields, we will be able to predict how varying amorphous silicate systems exhibit slow crack growth.

Evaluation of As-Received Green Liquor Dregs and Biomass Ash Residues from a Pulp and Paper Industry as Raw Materials for Geopolymers

This study aimed to investigate the impact of as-received biomass fly ashes (BFA) and green liquor dregs obtained from a pulp and paper plant in Brazil as substitutes for metakaolin in geopolymeric formulations. The properties of this type of waste material vary widely between different industrial plants. This study refrains from subjecting the waste materials to any form of pretreatment, taking into account their organic matter and particle size heterogeneity, requiring extensive characterization to evaluate their influence on the compressive strength, apparent open porosity, and water absorption of the geopolymeric samples. The objective was to assess their potential for upcycling purposes as an alternative to energy-intensive materials, such as ordinary Portland cement (OPC) and advanced ceramics. This potential arises from the ability of alkali-activated materials (AAM) to undergo curing at ambient temperatures, coupled with the possibility of compositions primarily derived from waste materials. To improve the sustainability of the products, the amorphous content of the raw material, which is more reactive than crystalline phases, was quantified and used as the base for mixture ratios. This approach aimed to reduce the requirement for alkaline activators, which have significant environmental impacts, while also increasing the waste content in the formulation. The incorporation of waste materials into the geopolymer matrix generally led to a reduction in the compressive strength compared to the benchmark metakaolin sample (19.4 MPa) but did not present a trend. The dregs led to values of 4.1 MPa at 25 wt% and 7.1 MPa at 50 wt%, a behavior that is somewhat counterintuitive, and BFA at 10 wt% presented 5.7 MPa. Nevertheless, the apparent open porosity remained at high levels for all the samples, close to 50%, and the compressive strength of most of them was over the values obtained for the metakaolin-only samples with mixture ratios calculated from the total composition instead of the amorphous composition. The decrease in strength and the increase in porosity were attributed to the specific characteristics of the waste materials, such as their high crystallinity, presence of organic matter, heterogeneous particle composition, and size. Overall, this study provides insight into the variations in geopolymerization based on the bulk and amorphous content of the aluminosilicate sources and how the characteristics of the waste materials influence the geopolymer matrix. It also highlights how calculating mixture ratios based on the amorphous composition improves the possibility of waste valorization through alkali activation. Additionally, it suggests that BFA and dregs might be effectively utilized in applications other than OPC substitution, such as adsorption, filtration, and catalysis.

High-Throughput Synthesis and Characterization Screening of Mg-Cu-Y Metallic Glass

Bulk metallic glasses can exhibit novel material properties for engineering scale components, but the experimental discovery of new alloy compositions is time intensive and thwarts the rate of discovery. This study presents an experimental, high-throughput methodology to increase the speed of discovery for potential bulk metallic glass alloys. A well-documented system, Mg-Cu-Y, was used as a model system. A laser additive manufacturing technique, directed energy deposition, was used for the in situ alloying of elemental powders to synthesize discrete compositions in the ternary system. The laser processing technique can supply the necessary cooling rates of 103–104 Ks−1 for bulk metallic glass formation. The in situ alloying enables the rapid synthesis of compositional libraries with larger sample sizes and discrete compositions than are provided by combinatorial thin films. Approximately 1000 discrete compositions can be synthesized in a day. Surface smoothness, as discerned by optical reflectivity, can suggest glass-forming alloys. X-ray diffraction coupled with energy dispersive X-ray spectroscopy can further refine amorphous alloy signatures and compositions. Transmission electron microscopy confirms amorphous samples. The tiered rate of amorphous alloy synthesis and characterization can survey a large compositional space and permits a glass-forming range to be identified within one week, making the process at least three orders of magnitude faster than other discrete composition techniques such as arc-melting or melt-spinning.

Prediction of glass-forming ability in ternary alloys based on machine learning method

In this paper, six machine learning (ML) models including k-nearest neighbour, adaptive boosting, gradient boosting regression tree, extreme gradient boosting tree, support vector regression (SVR) and random forest were built in the frame of ternary alloys to predict the critical size of glass formation (Dmax) based on 840 alloy data. Composition, atomic size difference, enthalpy of mixing, electronegativity difference, and valence electron concentration were selected as input features. The features were selected by Pearson correlation analysis and target value of Dmax was transformed into the logarithmic form. The determination coefficient and root mean square error were used to evaluate the prediction performance of models. The result showed that the SVR model has a good generalization ability. Additionally, the prediction ability of SVR was verified in Zr−Al−Co and La−Al−Co alloy systems. It is thus suggested that ML has great potential in predicting and pinpointing the amorphous composition with good glass-forming ability.

Optical and optoelectronic properties of (Ge2S8)100-xTex thin films for IR optical device fabrication

A detailed study of the optical and optoelectronic properties of (Ge2S8)100-xTex thin films for optical device fabrication is described in the present paper. Thin films of melt-quenched chalcogenide samples were deposited, on ultrasonically cleaned glass substrates, employing thermal evaporation technique. Transmission spectra were used to calculate the refractive index (n) and extinction coefficients (k). The refractive index increases from 2.187 to 2.329 by adding Te = 0 to 12. Dispersion parameters are evaluated using the WDD single oscillator model. The dielectric parameters real (εr) and imaginary (εi), electric modulus (M) and dielectric loss (tan δ) are used to evaluate the relaxation process in different compositions of (Ge2S8)100-xTex thin films. To further grasp the importance of amorphous chalcogenide compositions, we compute their optical conductivity (σ*op), electronic polarizability (αp), plasma frequency (ωp), metallization parameter (M), and refraction losses (RL) in optical devices. The dependency of Te content on the nonlinear refractive index (n2) and third-order susceptibility (χ(3)) is also calculated by an empirical formula, and it is found that the value of n2 increases from 11.938 × 10−12 to 20.615 × 10−12 esu, and the value of χ(3) rises from 6.8 × 10−13 to 12.472×10−13 esu with the addition of denser and higher atomic radius elements Te in the Ge-S system. The overall composition of Ge17.6S70.4Te12 is suitable as all-optical parameters show the maximum values that can be used for optical device purposes.

Mutual influence of the morphology and growth kinetics in binary crystalline blends of poly(butylene terephthalate) and polyarylate

The spherulitic morphology and crystallization behaviors of binary crystalline blends of poly(butylene terephthalate) (PBT) and polyarylate (PAr), based on bisphenol A, (27:73 isophthalic:terephthalic acids), are investigated herein. PBT and PAr crystallize simultaneously or sequentially; various crystallization behaviors and morphologies are observed. In the PBT-rich blends, PAr does not crystallize; the PBT spherulites coarsen as the PAr concentration increases. Non-crystallizable PAr is trapped inside the spherulites. The PBT spherulitic growth rate decreases when PAr is added and remains constant thereafter. For the 50/50 blends, PBT and PAr crystallize simultaneously, and their spherulites co-exist separately. The spherulitic growth rate of PBT increases with time while PAr is crystallizing, but it remains constant if PAr crystallizes prior. At a crystallization temperature of 250 °C, only PAr crystallizes; the non-crystallizable PBT is expelled from the PAr spherulites because the crystallization rate of PAr is low. The spherulites of PAr do not fill the space in the final crystallization stage. The crystallization rate of the binary crystalline PBT/PAr blends was notably influenced by the prior crystallization of the other component, and was due to the change of the amorphous composition in addition to the constraints of the crystals on the chain mobility.

A predicting model for determination of glass-forming compositions in Hf-Cu-Al(Ti, Ni) systems

One of the unsolved fundamental problems in the production of bulk metallic glasses (BMGs) is related to the development of a method/model for predicting local areas of amorphization in metallic glasses. Despite decades of intensive research, there are no reliable and physically based methods for predicting the compositions of multicomponent metal alloys with high glass-forming ability. Here, we propose a new model for predicting BMG compositions with approbation on Hf-Cu-Al(Ti,Ni) systems. Using new parameters ΘX−Y(X),ΘX−Y(Y), we predict the areas of formation of glass-forming compositions through search for a minimum of product of PHSS and Г parameters (where, PHSS - product of mixing enthalpy, configurational entropy and mismatch entropy; Г – geometric factor). Also, the proposed model predicts amorphous compositions in metallic systems by analyzing PHSS versus Dmax (maximum critical diameter). As a result, Hf0.23Cu0.65Ti0.12, Hf0.54Cu0.18Ni0.28, Hf0.42Cu0.48Al0.10 were successfully identified as the compositions with the best glass-forming ability (GFA).Our findings open up prospects for the development of reliable theoretical methods for predicting new metallic glasses.

Tuning Amorphous Selenium Composition with Tellurium to Improve Quantum Efficiency at Long Wavelengths and High Applied Fields.

Amorphous selenium (a-Se) is a large-area compatible photoconductor that has received significant attention toward the development of UV and X-ray detectors for a wide range of applications in medical imaging, life science, high-energy physics, and nuclear radiation detection. A subset of applications require detection of photons with spectral coverage from UV to infrared wavelengths. In this work, we present a systematic study utilizing density functional theory simulations and experimental studies to investigate optical and electrical properties of a-Se alloyed with tellurium (Te). We report hole and electron mobilities and conversion efficiencies for a-Se1-xTex (x = 0, 0.03, 0.05, 0.08) devices as a function of applied field, along with band gaps and comparisons to previous studies. For the first time, these values are reported at high electric field (>10 V/μm), demonstrating recovery of quantum efficiency in Se-Te alloys. A comparison to the Onsager model for a-Se demonstrates the strong field dependence in the thermalization length and expands on the role of defect states in device performance.

A hydrogel-assisting surface-confined corrosion strategy toward self-supported amorphous NiFe-layered double hydroxides enabling high-performance hybrid solid-state supercapacitors

Layered double hydroxides (LDHs) are promising energy materials for supercapacitors. It is demonstrated that the integrated performance of the amorphous LDHs is superior to that of crystalline materials. However, it is still a great obstacle to producing amorphous LDHs. Herein, a simple and facile strategy is proposed to synthesize the self-supported amorphous NiFe-LDHs using a surface-confined method. The corrosion process takes place in a cost-effective hydrogel at ambient temperature and pressure, which can synchronously change the chemical structure and morphology of the NiFe-LDHs. This method is also proved to be effective in fabricating S-doped amorphous NiFe-LDHs. The as-prepared products show excellent electrochemical performance in the charge-discharge process with fast kinetics, low impedance, good stability, and significant capacity, which is superior to most reported crystalline electrode materials. Moreover, the assembled hybrid solid-state supercapacitor devices display excellent capacitive performance including high energy density, superb rate capability and outstanding long-term cycling stability. This work offers a new sight into economically synthesizing amorphous mixed-metal compositions for high-performance supercapacitors.