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At least 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Zr(Ni2As)2 by Materials Project

Zr(Ni2As)2 crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Zr2+ is bonded to six equivalent As3- atoms to form a mixture of edge and corner-sharing ZrAs6 octahedra. The corner-sharing octahedral tilt angles are 41°. There are two shorter (2.84 Å) and four longer (2.87 Å) Zr–As bond lengths. Ni1+ is bonded in a trigonal non-coplanar geometry to three equivalent As3- atoms. All Ni–As bond lengths are 2.36 Å. As3- is bonded in a 9-coordinate geometry to three equivalent Zr2+ and six equivalent Ni1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zr(NF3)2 by Materials Project

ZrF4(NF)2 crystallizes in the orthorhombic Pca2_1 space group. The structure is one-dimensional and consists of sixteen monofluoroamine molecules and four ZrF4 ribbons oriented in the (1, 0, 0) direction. In each ZrF4 ribbon, there are two inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded to six F1- atoms to form a mixture of distorted corner and face-sharing ZrF6 octahedra. The corner-sharing octahedral tilt angles are 34°. There are a spread of Zr–F bond distances ranging from 1.92–2.20 Å. In the second Zr4+ site, Zr4+ is bonded to six F1- atoms to form a mixture of distorted corner and face-sharing ZrF6 octahedra. The corner-sharing octahedral tilt angles are 34°. There are a spread of Zr–F bond distances ranging from 1.92–2.24 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Zr4+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Zr4+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Zr4+ atom. In the fourth F1- site, F1- is bonded in an L-shaped geometry to two Zr4+ atoms. In the fifth F1- site, F1- is bonded in an L-shaped geometry to two Zr4+ atoms. In the sixth F1- site, F1- is bonded in an L-shaped geometry to two Zr4+ atoms. In the seventh F1- site, F1- is bonded in a bent 150 degrees geometry to two Zr4+ atoms. In the eighth F1- site, F1- is bonded in a single-bond geometry to one Zr4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zr(SiPd)3 by Materials Project

Zr(PdSi)3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Zr4+ is bonded to eight equivalent Si4- atoms to form distorted ZrSi8 hexagonal bipyramids that share corners with four equivalent PdSi4 tetrahedra, edges with four equivalent ZrSi8 hexagonal bipyramids, edges with two equivalent PdSi4 tetrahedra, and faces with four equivalent ZrSi8 hexagonal bipyramids. There are four shorter (2.81 Å) and four longer (2.95 Å) Zr–Si bond lengths. There are two inequivalent Pd+2.67+ sites. In the first Pd+2.67+ site, Pd+2.67+ is bonded to four Si4- atoms to form PdSi4 tetrahedra that share corners with four equivalent ZrSi8 hexagonal bipyramids, corners with two equivalent PdSi4 tetrahedra, and edges with two equivalent ZrSi8 hexagonal bipyramids. There are two shorter (2.43 Å) and two longer (2.50 Å) Pd–Si bond lengths. In the second Pd+2.67+ site, Pd+2.67+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Pd–Si bond distances ranging from 2.51–2.58 Å. There are two inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 8-coordinate geometry to four equivalent Zr4+, three Pd+2.67+, and one Si4- atom. The Si–Si bond length is 2.36 Å. In the second Si4- site, Si4- is bonded in a 8-coordinate geometry to eight Pd+2.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

An experimentally validated mesoscale model for the effective thermal conductivity of U-Zr fuels

An experimentally validated mesoscale model was developed to simulate the effective thermal conductivity (ETC) of metallic U and U–Zr nuclear fuels. The effects of microstructure, temperature, composition, and interfacial thermal resistance (ITR) were investigated. Companion experiments were conducted to validate the model. The numerical simulations clearly demonstrate that accounting for the interface (Kapitza) thermal resistance and Zr precipitation is necessary to improve the model predictions. The dependence of the effective Kapitza resistance of depleted-U and U-10Zr on temperature was determined. Finally, for both materials, the largest difference between the model calculations and the experimental data was about 4.5%, which is within the precision of the experimental measurements.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2024

Breaking Barriers in Chalcogenide Perovskite Synthesis: A Generalized Framework for Fabrication of BaMS 3 (M═Ti, Zr, Hf) Materials

Abstract Chalcogenide perovskites have garnered increasing attention as stable, non‐toxic alternatives to lead halide perovskites. However, their conventional synthesis at high temperatures (>1000 °C) has hindered widespread adoption. Recent studies have developed low‐to‐moderate temperature synthesis methods (<600 °C) using reactive precursors, yet a comprehensive understanding of the pivotal factors affecting reproducibility and repeatability remains elusive. This study delineates the critical factors in the low‐temperature synthesis of BaMS 3 (M═Zr, Hf, Ti) compounds and presents a generalized framework. Innovative approaches are developed for synthesizing BaMS 3 compounds using this framework involving organometallics for solution deposition. The molecular precursor routes, employing metal acetylacetonates to generate soluble metal–sulfur bonded complexes and metal–organic compounds to produce soluble metal‐thiolate, metal‐isothiocyanate, and metal‐trithiocarbonate species, are demonstrated to yield carbon‐free BaMS 3 . These methods have achieved the most contiguous films of BaZrS 3 and BaHfS 3 using solution deposition to date. Furthermore, a hybrid solution processing method involving stacking sputter‐deposited Zr and solution‐deposited BaS layers is employed to synthesize a contiguous, oxygen‐free BaZrS 3 film. The diffuse reflectance measurements indicate a direct bandgap of ≈ 1.85 eV for the BaZrS 3 films and ≈ 2.1 eV for the BaHfS 3 film under investigation.

25 ENERGY STORAGE↗
DOE OSTI2022

CeO 2 Doping of Hf 0.5 Zr 0.5 O 2 Thin Films for High Endurance Ferroelectric Memories

Ferroelectric switching is demonstrated in CeO 2 -doped Hf 0.5 Zr 0.5 O 2 (HZCO) thin films with application in back-end-of-line compatible embedded memories. At low cerium oxide doping concentrations (2.0–5.6 mol%), the ferroelectric orthorhombic phase is stabilized after annealing at temperatures below 400 °C. HZCO ferroelectrics show reliable switching characteristics beyond 10 11 cycles in TiN/HZCO/TiN capacitors, several orders of magnitude greater than identically processed Hf 0.5 Zr 0.5 O 2 (HZO) capacitors, without sacrificing polarization and retention. Internal photoemission and photoconductivity experiments show that CeO 2 -doping introduces in-gap states in HZCO that are nearly aligned with TiN Fermi level, facilitating electron injection through these states. Furthermore, the enhanced average bulk conduction, which may lead to more uniform thermal dissipation in the HZCO films, delays irreversible degradation via breakdown that leads to device failure after repeated programming cycles.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Phase Transformation Driven by Oxygen Vacancy Redistribution as the Mechanism of Ferroelectric Hf 0.5 Zr 0.5 O 2 Fatigue

As a promising candidate for nonvolatile memory devices, the hafnia-based ferroelectric system has recently been a hot research topic. Although significant progress has been made over the past decade, the endurance problem is still an obstacle to its final application. In perovskite-based ferroelectrics, such as the well-studied Pb[Zr x Ti 1-x ]O 3 (PZT) family, polarization fatigue has been discussed within the framework of the interaction of charged defects (such as oxygen vacancies) with the moving domains during the switching process, particularly at the electrode-ferroelectric interface. Armed with this background, a hypothesis is set out to test that a similar mechanism can be in play with the hafnia-based ferroelectrics. The conducting perovskite La-Sr-Mn-O is used as the contact electrode to create La 0.67 Sr 0.33 MnO 3 / Hf 0.5 Zr 0.5 O 2 (HZO)/ La 0.67 Sr 0.33 MnO 3 capacitor structures deposited on SrTiO 3 -Si substrates. Nanoscale X-ray diffraction is performed on single capacitors, and a structural phase transition from polar o-phase toward non-polar m-phase is demonstrated during the bipolar switching process. The energy landscape of multiphase HZO has been calculated at varying oxygen vacancy concentrations. Based on both theoretical and experimental results, it is found that a polar to non-polar phase transformation caused by oxygen vacancy redistribution during electric cycling is a likely explanation for fatigue in HZO.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Linker Vacancy Engineering of a Robust ftw–type Zr–MOF for Hexane Isomers Separation

Discrimination of physically similar molecules by porous solids represents an important yet challenging task in industrially relevant chemical separations. Precisely controlled pore dimension and/or tailored pore surface functionality are crucial to achieve high-efficiency separation. Metal-organic frameworks (MOFs) are promising candidates for these challenging separations in light of their structural diversity as well as highly adjustable pore dimension/functionality. We report here a microporous, ftw-type Zr-based MOF structure, HIAM-410 (HIAM=Hoffmann Institute of Advanced Materials), built on hexanuclear Zr 6 cluster and pyrene-1,3,6,8-tetracarboxylate (ptc 4– ). Its crystallographic structure has been determined using continuous rotation electron diffraction (cRED) technique combined with Rietveld refinement against powder X-ray diffraction data, aided by low-dose high-resolution transmission electron microscopy (HRTEM) imaging. The compound features exceptional framework stability that is comparable to the prototype MOF UiO-66. Interestingly, the linker vacancies in the pristine MOF structure could be partially restored by post-synthetic linker insertion. Its separation capability of hexane isomers is enhanced substantially upon the linker vacancy engineering. As a result, the restored structure exhibits efficient splitting of monobranched and dibranched hexane isomers at both room temperature and industrially relevant temperature.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Gallium‐Doping Effects on Structure, Lithium‐Conduction, and Thermochemical Stability of Li 7‐3 x Ga x La 3 Zr 2 O 12 Garnet‐Type Electrolytes

Abstract One of the most promising electrolytes for all‐solid‐state lithium batteries is Li 7 La 3 Zr 2 O 12 . Previously, their thermodynamic stability, Li‐ion conductivity, and structural features induced by Ga‐doping have not been empirically determined or correlated. Here, their interplay was examined for Li 7−3 x Ga x La 3 Zr 2 O 12 with target x Ga=0, 0.25, 0.50, 0.75, and 1.00 atoms per formula unit (apfu). Formation enthalpies, obtained with calorimetry and found to be exothermic at all compositions, linearly decreased in stability with increased x Ga. At dilute x Ga substitution, the formation enthalpy curve shifted stepwise endothermically, and the conductivity increased to a maximum, coinciding with 0.529 Ga apfu. This correlated with percolation threshold analysis (0.558 Ga apfu). Further substitution (0.787 Ga apfu) produced a large decrease in the stability and conductivity due to a large increase in point defects and blocked Li‐migration pathways. At x Ga=1.140 apfu, a small exothermic shift was related to defect cluster organization extending the Li hopping distance and decreased Li‐ion conductivity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

NASICON Li 1.2 Mg 0.1 Zr 1.9 (PO 4 ) 3 Solid Electrolyte for an All‐Solid‐State Li‐Metal Battery

Abstract A thin solid electrolyte with a high Li + conductivity is used to separate the metallic lithium anode and the cathode in an all‐solid‐state Li‐metal battery. However, most solid Li‐ion electrolytes have a small electrochemical stability window, large interfacial resistance, and cannot block lithium‐dendrite growth when lithium is plated on charging of the cell. Mg 2+ stabilizes a rhombohedral NASICON‐structured solid electrolyte of the formula Li 1.2 Mg 0.1 Zr 1.9 (PO 4 ) 3 (LMZP). This solid electrolyte has Li‐ion conductivity two orders of magnitude higher at 25 °C than that of the triclinic LiZr 2 (PO 4 ) 3 . 7 Li and 6 Li NMR confirm the Li‐ions in two different crystallographic sites of the NASICON framework with 85% of the Li‐ions having a relatively higher mobility than the other 15%. The anode–electrolyte interface is further investigated with symmetric Li/LMZP/Li cell testing, while the cathode–electrolyte interface is explored with an all‐solid‐state Li/LMZP/LiFePO 4 cell. The enhanced performance of these cells enabled by the Li 1.2 Mg 0.1 Zr 1.9 (PO 4 ) 3 solid electrolyte is stable upon repeated charge/discharge cycling.

Zhou, Qiongyu↗
DOE OSTI2021

Local ordering in disordered Nd x Zr 1-x O 2-0.5x pyrochlore as observed using neutron total scattering

Pyrochlore complex oxides (A 2 B 2 O 7 ) are an important class of fluorite-derivative ceramics with exceptional chemical and structural versatility which make them ideal model systems for studying disordering mechanisms over a range of spatial scales. Here, neutron total scattering methods were used to analyze the structural behavior in the non-stoichiometric series Nd x Zr 1-x O 2-0.5x (0.5 ≤ x ≤ 0.23) as a function of Nd content, x. Characterization of the structure functions using Rietveld refinement and the pair distribution functions with small-box refinement reveal complex disordering pathways; the average, long-range phase changes over a very narrow compositional range from pyrochlore ($Fd\bar{3}m$) to defect fluorite ($Fm\bar{3}m$) through full randomization of the cation and anion sublattices at x ~ 0.31, while the local, short-range structure continuously adopts a weberite-type atomic arrangement (C222 1 ). Comparison to a previously studied Ho 2 Ti 2-x Zr x O 7 solid solution series reveals how changes in chemical composition and stoichiometry modify defect formation and determine how disordering progresses across different length scales in pyrochlore oxides.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Additively manufactured novel Al-Cu-Sc-Zr alloy: Microstructure and mechanical properties

An in-depth understanding of microstructure and resultant properties is paramount in the design of a novel alloy system, especially for additive manufacturing (AM). The present investigation aims to characterize a prototypical AM Al alloy with great potential for structural applications. An Al-1.5Cu-0.8Sc-0.4Zr alloy designed using integrated computational material engineering was printed using the laser powder bed fusion AM process. This novel alloy shows promising combination of strength and ductility in as-built and peak-aged conditions. This improvement in the tensile properties is attributed to the presence of both coherent L1 2 Al 3 Sc/Al 3 (Sc,Zr) precipitates and Cu-rich regions. The microstructures were studied via extensive microscopy at different length scales using X-ray microscopy, scanning electron microscopy, and transmission electron microscopy. Fractography revealed that the columnar grain boundaries in as-built condition allow easy slip transfer as compared to the equiaxed grains, with the apex of the melt pool acting as the crack nucleation site. Furthermore, the peak aged condition resulted in improved strength while marginally sacrificing ductility due to precipitates decorating dislocations, grain boundaries and melt pool boundaries thus acting as obstacles to slip transfer.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Creep deformation and cavitation in an additively manufactured Al-8.6Cu-0.4Mn-0.9Zr (wt%) alloy

Creep deformation and cavitation were investigated at 300 ºC in both tension and compression for an additively manufactured Al-8.6Cu-0.5Mn-0.9Zr (wt%) alloy in the as-fabricated state and after various aging treatments (aging at 300 °C/200 h or 350 °C/24 h and overaging at 400 °C/200 h). Creep mechanisms at 300 °C were determined by relating the measured creep response to corresponding microstructural and X-ray computed tomography observations. In compression, alloys in the as-fabricated and two aging conditions exhibited similarly high creep resistance. Overaging (400 °C/200 h) led to substantial coarsening of intragranular θ-Al2Cu precipitates and an expected drop in their Orowan strengthening contribution. In tension, minimum strain rates comparable to those in compression were obtained at any given stress; however, upon accumulation of some plastic strain in the matrix, creep cavities started to form, leading to accelerated tertiary stage creep deformation and rupture. Cavitation occurred exclusively along melt pool boundaries due to locally enhanced diffusion enabled by (i) large grain-boundary area in adjacent fine-grained zones and (ii) localization of creep strain in nearby heat-affected zones. Although cavity growth was initially diffusion-controlled, its rate was determined by matrix creep rate, consistent with constrained cavity growth mechanisms. This study reveals how microstructural complexities induced by the additive manufacturing process affect the creep and cavitation behavior of Al-Cu-Mn-Zr alloys. The underlying creep and cavitation mechanisms uncovered in this study point to pathways that improve the high-temperature properties of additively manufactured alloys.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Influence of thermal treatment on structure and catalytic performance of ceria-zirconia supported copper oxide (CuO x /Ce y Zr 1-y O 2 ) catalysts for CO oxidation

Copper oxide (CuO x ) supported on ceria-zirconia (Ce y Zr 1-y O 2 , y = 1.0, 0.5, 0.0) catalysts were investigated to elucidate the effects of thermal treatment on their physicochemical properties and catalytic performance in carbon monoxide (CO) oxidation. Here, the catalysts were synthesized via a one-pot chemical vapor deposition (OP-CVD) method at 700˚C and 900˚C with controlled Cu loading. Characterization techniques, including synchrotron X-ray diffraction (S-XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma spectroscopy (ICP), and N 2 adsorption-desorption, were implemented to probe the crystalline structure, molecular and electronic structure, oxygen vacancies, specific surface area (SSA) and metal loading. CO oxidation was chosen as a model reaction to explore the structure-catalytic performance relationship. A ∼100% CO conversion was achieved at < 150˚C, particularly with the CuO x /CeO 2 catalyst calcined at 700˚C. In contrast, calcination at 900˚C caused a ∼90% decrease in SSA and a ∼24% increase in T 50 . Activity tests revealed that increasing ZrO 2 content lowered CO oxidation activity despite generating more defect sites. In-situ measurement of the 700 °C calcined samples revealed the presence of stable and unstable defects in CuO x /Ce 0.5 Zr 0.5 O 2 and CeO 2 respectively, which play a key role in the activity of the catalysts. The results highlight that catalytic performance is closely related to the SSA. Furthermore, an optimum calcination temperature favor significant oxygen vacancy formation with required CuO x -support interactions, enhancing redox properties and catalytic performance.

36 MATERIALS SCIENCE↗
DOE OSTI2025

The effect of copper additives on hybrid Zr-based chemical conversion coating morphology and chemical compositions

In the realm of corrosion protection, Zr-based conversion coatings offer an environmentally friendly, chromate-free alternative to conventional coating. This study uses advanced X-ray, electron microscopy and electrochemical testing techniques to better understand the impact of varying Cu²⁺ ion concentrations on the characteristics of Zr-based coatings on Fe substrates. Our findings demonstrate that within the tested conditions, higher Cu²⁺ additive concentrations at 40 ppm enhance surface characteristics, increasing stability towards anti-corrosion capability, particularly under NaCl treatment. Conversely, at a lower Cu²⁺ concentration of 20 ppm, coatings exhibited more significant dissolution of Cu clusters and increased vulnerability to chloride-induced degradation. X-ray photoelectron spectroscopy and synchrotron X-ray fluorescence (XRF) and X-ray absorption near edge structure (XANES) spectroscopy analyses revealed Cu²⁺ formation in Cu20, while Cu40 retained its metallic state (Cu⁰) with a slower reaction rate. Cu20 offers some protection but lacks durability, whereas in Cu40, lower I corr , and enhance corrosion resistance, making it ideal for protective coatings in salt-water environments. This study underscores the importance of balancing Cu²⁺ ions concentration in the coating solution to optimize performance, highlighting the role of Cu in enhancing both surface properties and long-term stability.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Spectroscopic evaluation of tribologically-induced changes in surface chemistry of Zr-based bulk metallic glass

Bulk metallic glasses (BMGs) are promising structural materials owing to their high elastic limit and yield strength-to-weight ratio. While BMGs also exhibit attractive tribological properties (e.g., high wear resistance), the scientific basis for this behavior is not yet established. In particular, tribologically-induced changes in surface chemistry upon sliding are still an open topic of research. Here, we evaluated by X-ray photoelectron spectroscopy (XPS) the evolution of the surface chemistry of Vitreloy 105 (a Zr-rich BMG) upon sliding under different contact conditions against a tungsten carbide countersurface. The spectroscopic results indicate that the relative fraction of the metallic elements in the near-surface region is not affected by the sliding speed when the applied contact pressure is lower than 1.37 GPa, while a decrease in metallic zirconium was observed at lower sliding speeds and higher applied contact pressure (i.e., 1.71 GPa). Based on the spectroscopic results, a model is proposed for the effect of mechanical stress on the extent of oxidation of the near-surface region of Zr-based BMGs. In conclusion, the results of this work provide novel insights into the surface phenomena occurring on BMGs upon sliding and add significantly to our understanding of the tribological response of this class of promising structural materials.

Bulk metallic glasses↗
DOE OSTI2020

W-ZrC composites prepared by reactive melt infiltration of Zr 2 Cu alloy into binder jet 3D printed WC preforms

W-ZrC composites were successfully prepared by reactive melt infiltration (RMI) of stoichiometric and excess amounts of Zr 2 Cu into sintered and un-sintered WC preforms made from binder jet 3D printing. The focus of this work was to study the conversion of reactant powders and liquid infiltrant with varying preform density and infiltrant amount by controlling the processing time to reach high conversion yield while understanding the phase composition, microstructure, and hardness. To investigate the effect of time, the reactive melt infiltration was conducted at 1400 °C for 2, 4 and 8 h in a furnace with 96% Ar - 4% H2 gas atmosphere. The increase in reaction time from 2 to 8 h increased the W and W 2 C phase contents and decreased the ZrC phase content when using sintered WC preforms. Samples prepared from un-sintered WC preforms exhibited improved reactive melt infiltration compared to sintered samples, and there was no detectable W 2 C phase and nearly full consumption of WC. Similar to sintered WC samples, the content of W and ZrC phases increased with the increase in time from 2 to 8 h. The interfaces and phases at reaction interfaces were investigated using electron diffraction analysis and S/TEM-EDS to understand material stability; the phases were identified and consistent with XRD analysis. Additionally, there was no Cu present at the interfaces. Increasing the amount of infiltrant led to better reactive melt infiltration. In general, the hardness increased with reaction time and the highest Vickers hardness was found in the W-ZrC sample formed from sintered WC reacted with excess Zr 2 Cu. Finally, this research addresses the critical comparison of sintering and RMI time and shows that by using un-sintered samples for 8 h we are able to achieve W-ZrC composites with fewer undesired phases.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Tailoring Cu-Zr gradient nanoglass structures: Influence of nanoparticle size and cooling rates on glass-glass interfaces

The study of gradient nanoglasses (GNGs) has gained attention due to their unique mechanical properties and potential applications in advanced materials. This study employs molecular dynamics simulations to synthesize a GNG using Cu-Zr metallic glass nanoparticles (NPs) sized from 3 to 15 nm. The NPs were produced by melting and quenching metallic clusters at a relatively slow quench rate of 10 9 K/s. The synthesis of GNG is elucidated along with the characterization of its heterogeneous metallic glass nanostructure. A seamless GNG structure is formed through cold compression of Cu 64 Zr 36 amorphous NPs of varying sizes. The influence of NP size on the GNG structure is investigated, utilizing deeply relaxed NPs, which exhibit a characteristic Cu segregation pattern on their surfaces. The results highlight an increase in structural heterogeneity due to heterogeneous mass transport and the development of local composition and density variations caused by Cu segregation at glass-glass interfaces (GGIs). A reduction in NP size is correlated with decreased Cu atomic displacements and local density at GGIs, suggesting that larger NPs may produce stronger GGIs. This research presents a novel methodology for synthesizing heterogeneous metallic glasses, demonstrating the capacity to control and customize nanostructure heterogeneity through the manipulation of NP sizes and cooling rates. Furthermore, these findings enhance our understanding of structural evolution during nanoglass synthesis and lay the foundation for further exploration in nanomaterial synthesis and characterization.

36 MATERIALS SCIENCE↗