Metals Au Research Articles

Recent chemical methods for metals recovery from printed circuit boards: A review

AbstractAs the volume of e-waste continues to rise, it is crucial to sustainably manage printed circuit boards (PCBs) and their valuable metal components. PCBs are ubiquitous in modern society, powering a variety of electronic devices. The metal resource crisis and the imperative for a low-carbon circular economy have accelerated the development of e-waste recycling technology. High-value discarded PCBs represent a vital component of e-waste. However, discarded PCBs are deemed hazardous to the ecosystem due to the presence of heavy metals and brominated organic polymers. Thus, recycling metals from discarded PCBs is not only a strategic necessity for fostering a green ecological civilisation but also a crucial guarantee for ensuring a safe supply of mineral resources. This comprehensive review gives the profound details of PCBs, and the performance of and advances in the latest chemical metal recovery methods. Reviewing the latest metal recovery processes, we explored the application of diverse leaching agents, including ionic liquids (ILs), deep eutectic solvents (DESs), organic acids and amino acids. These solvents were assessed in terms of their recovery efficiencies, and most of them demonstrated excellent leaching performance. The role of optimising leaching parameters such as concentration, oxidants, pH, particle size, solid-to-liquid ratios (S/L), temperature, and contact time is underscored, offering insights into achieving sustainable PCB recycling practices. Most of these recent leaching methods successfully extracted base metals (Cu, Fe, Zn, Sn, etc.), as well as precious metals (Au and Ag), achieving leaching efficiencies exceeding 90.0%. Interestingly, their effectiveness can compete with that of traditional hydrometallurgical methods.

Emerging Non-Noble-Metal Atomic Layer Deposited Copper as Seeds for Electroless Copper Deposition.

Copper metal catalyst seeds have recently triggered much research interest for the development of low-cost and high-performance metallic catalysts with industrial applications. Herein, we present metallic Cu catalyst seeds deposited by an atomic layer deposition method on polymer substrates. The atomic layer deposited Cu (ALD-Cu) can ideally substitute noble metals Ag, Au, and Pd to catalyze Cu electroless deposition. The optimized deposition temperature and growth cycles of an ALD-Cu catalyzed seed layer have been obtained to achieve a flexible printed circuit (FPC) with a high performance electroless plating deposited Cu (ELD-Cu) film. The ELD-Cu films on the ALD-Cu catalyst seeds grown display a uniform and dense deposition with a low resistivity of 1.74 μΩ·cm, even in the through via and trench of substates. Furthermore, the ALD-Cu-catalyzed ELD-Cu circuits and LED devices fabricated on treated PI also demonstrate excellent conductive and mechanical features. The remarkable conductive and mechanical characteristics of the ALD-Cu seed catalyzed ELD-Cu process demonstrate its tremendous potential in high-density integrated FPC applications.

Ultrahigh Nonlinear Responses from MXene Plasmons in the Short-Wave Infrared Range.

Surface plasmons in 2D materials such as graphene exhibit exceptional field confinement. However, the low electron density of majority of 2D materials, which are semiconductors or semimetals, has limited their plasmons to mid-wave or long-wave infrared regime. This study demonstrates that a 2D Ti3C2Tx MXene with high electron density can not only support strong plasmon confinement with an acoustic plasmon mode in the short-wave infrared region, but also provide ultrahigh nonlinear responses. The acoustic MXene plasmons (AMPs) in the MXene (Ti3C2Tx)-insulator (SiO2)-metal (Au) nanostructure generate in the 1.5-6.0 µm wavelength range, exhibiting a two orders of magnitude reduction in wavelength compared to wavelength in free space. Furthermore, AMP resonators with patterned Au rods exhibit a record-high nonlinear absorption coefficient of 1.37 × 10-2 mW-1 at wavelength of 1.56 µm, ≈3 orders of magnitude greater than the highest value recorded for other 2D materials. These results indicate that MXenes can overcome fundamental plasmon wavelength limitations of previously studied 2D materials, providing groundbreaking opportunities in nonlinear optical applications, including all-optical processing and ultrafast optical switching.

High performance methyl salicylate gas sensor based on noble metal (Au, Pt) decorated WO3 nanofibers

Methyl salicylate (MeSa) is known as a volatile plant pathogen biomarker and a chemical warfare agent simulant. Herein, high performance MeSa gas sensors were developed by optimizing morphology and composition of noble metal decorated tungsten trioxide (WO3) nanofibers. Using optimized nanofibers, 100 ppb of MeSa were readily sensed in dry air whereas the calculated low limit of detection (LLOD) is expected to be in a few tens of ppb. Pt-WO3 (1.1 at% Pt) nanofibers also show an excellent selectivity over other volatile organic compounds including aromatic compounds (i.e., benzene, toluene, ethyl benzene, p-xylene). Systematic characterization of sensors in environments with different oxygen contents indicated that surface carrier concentration significantly altered as a function of Au and Pt content. Although 1.7 at% Au-WO3 nanofibers based sensor has higher sensing response toward MeSa, 1.1 at% Pt-WO3 nanofibers were found to be a more promising sensing material for MeSa detection because of higher selectivity over other VOCs and lower calculated LLOD ( ∼41 ppb).

Efficient recovery of Cr(VI), Au(III), and Pd(II) using physically crosslinked aminoclay/polyvinyl alcohol composite microgels generated by microfluidics

Chemically crosslinked hydrogel adsorbents are typically produced using highly toxic agents for crosslinking, posing risks to both human health and the environment. In this study, we successfully demonstrated the fabrication of a physically crosslinked Fe–aminoclay (AC)/polyvinyl alcohol (PVA) composite microgel. This was achieved using a microfluidic approach to generate water-in-oil-in-water (W/O/W) double-emulsion droplets, eliminating the need for chemical crosslinkers. Compared to its chemically crosslinked counterpart, this physically crosslinked Fe–AC/PVA microgel showed superior performance in recovering the metals Cr(VI), Au(III), and Pd(II) from an aqueous solution. This enhanced capability was attributed to the abundance of free amine functional groups and a microgel structure that was conducive to metal ion adsorption. The physically crosslinked microgel demonstrated a maximum adsorption capacity of 203.7 mg/g for Cr(VI), 241.3 mg/g for Au(III), and 275.8 mg/g for Pd(II), compared to 144.3, 181.1, and 222.5 mg/g, respectively, for the chemically crosslinked microgel. The adsorption isotherms and kinetics for these metals conformed to the Sips isotherm and pseudo-second-order models, respectively, suggesting that chemical adsorption was the dominant mechanism. Furthermore, embedding magnetic nanoparticles in the Fe–AC/PVA microgel enabled straightforward separation and regeneration from an aqueous solution. The Fe–AC/PVA composite microgel also demonstrated excellent reusability, maintaining an adsorption efficiency of over 78 % across five consecutive cycles.

Two-Coordinate Thermally Activated Delayed Fluorescence Coinage Metal Complexes: Molecular Design, Photophysical Characters, and Device Application.

Since the emergence of the first green light emission from a fluorescent thin-film organic light emitting diode (OLED) in the mid-1980s, a global consumer market for OLED displays has flourished over the past few decades. This growth can primarily be attributed to the development of noble metal phosphorescent emitters that facilitated remarkable gains in electrical conversion efficiency, a broadened color gamut, and vibrant image quality for OLED displays. Despite these achievements, the limited abundance of noble metals in the Earth's crust has spurred ongoing efforts to discover cost-effective electroluminescent materials. One particularly promising avenue is the exploration of thermally activated delayed fluorescence (TADF), a mechanism with the potential to fully harness excitons in OLEDs. Recently, investigations have unveiled TADF in a series of two-coordinate coinage metal (Cu, Ag, and Au) complexes. These organometallic TADF materials exhibit distinctive behavior in comparison to their organic counterparts. They offer benefits such as tunable emissive colors, short TADF emission lifetimes, high luminescent quantum yields, and reasonable stability. Impressively, both vacuum-deposited and solution-processed OLEDs incorporating these materials have achieved outstanding performance. This review encompasses various facets on two-coordinate TADF coinage metal complexes, including molecular design, photophysical characterizations, elucidation of structure-property relationships, and OLED applications.

Interface polarity brings a way to modulate magneto-optical effect of cubic Ni2+/Fe3+ co-doped Bi25FeO40 film: Implications in piezoelectricity

Cubic Sillenite Bi25FeO40 (BFO) could become a new magneto-optical material due to its high concentration of Bi3+ and no birefringence. But its weak magnetism causes the magneto-optical properties to be far from the requirements of practical applications. Doping magnetic Fe3+ and Ni2+ ions to improve the magnetism and magneto-optical properties of BFO (Bi19Ni2.8Fe4.2O40) film on fluorine-doped tin oxide (BNFO/FTO) is discussed in this paper. Another focus of this paper is to discuss the magneto-optical properties modulated by the electric field. The cubic BNFO film has weak piezoelectric effects, which makes it difficult to modulate its magneto-optical effect by electric field. A polarity symmetry induced by the Schottky junction between Au metal layer and BNFO semiconductor layer (Au/BNFO) compensates for cubic symmetry, and the piezoelectric effect can be improved. By applying an electric field, its magnetic circular dichroism (MCD) ellipticity |ΨF| gradually decreases as a direct current voltage from 0 V to 10 V in a magnetic field of 2500 Oe, demonstrating the feasibility of this strategy. These results indicate a new way for highly symmetric magneto-optical materials to modulate magneto-optical effects in electric fields.

A sustainable redox-active electrocatalyst utilizing natural quercetin-infused MWCNT for ultra-sensitive detection of environmental Cr(VI) contaminants

Hexavalent chromium (Cr(VI)), classified as a Group 1 carcinogen, is a widely acknowledged water pollutant, posing significant public health risks. The persisting challenge involves the development of sensitive and cost-effective methods for the detection and monitoring of Cr(VI) species at the concentration level recommended by the World Health Organization (WHO), which is 50 ppb (960 nM), in water sources. In the electrochemical detection of Cr(VI), modified electrodes utilizing precious metals (Au and Ag) and toxic organic redox mediators (Thionine, methylene blue, quionone, bisphenol and phenosafranine) have been employed. In this work, as an new platform, green electrochemical approach based on parsley-plant based natural quercetin (Qn-Redox) infused MWCNT modified glassy carbon electrode, designated as GCE/MWCNT@Qn-Redox, has been introduced for highly-effective electrocatalytic reduction and sensing of Cr(VI) species in pH 2 KCl-HCl solution. The as prepared GCE/MWCNT@Qn-Redox showed highly redox active surface confined peak at Eo = 0.550 V vs Ag/AgCl with surface excess value, 10.31 × 10−9 mol cm−2. Extensive physicochemical, spectroscopic, molecular characterization, and electrochemical control experiments confirm the identity of the entrapped molecular species in the green electrode as quercetin. By using scanning-electrochemical technique, the electroactive site of the green-electrode was imaged using Fe(CN)63−/Fe(CN)64− redox couple. The green-electrode showed excellent electrocatalytic Cr(VI) reduction signal where the Qn-Redox peak appears without any fouling problem. As a practical application, a portable batch-injection analysis coupled with three-in-one screen-printed electrode modified with MWCNT@Qn-Redox, which exhibitted a detection limit of 203 nM (S/N = 3), has been demonstrated for real time monitoring of toxic Cr(VI) species in tannery industries contaminated water samples. Given the electrochemical foundation of this approach, it holds promise for various sustainable electroanalytical assays in the future.

Metal (Cu, Ag, and Au) Doping-Induced Tunable Optical Properties of Cadmium Hydroxide for Optoelectronic Applications

Metal (Cu, Ag, and Au) Doping-Induced Tunable Optical Properties of Cadmium Hydroxide for Optoelectronic Applications

Modeling Hexaazacylcododeca Metal Complexes as a Radical Trapping Antioxidant: Prospects as a Potential Drug

AbstractFree radicals produced due to the disturbance in homeostasis bring about oxidative stress causing various diseases. This oxidative stress can be prevented by using antioxidants. In this article, a hexaazacylcododeca copper complex is reported as a radical‐trapping antioxidant (RTA). A detailed mechanistic study suggests that the designed complex is capable of trapping six radicals. The study confirms Path 6 as the most probable pathway, which is the radical addition to the ethene moiety of the complex. Moreover, it has a lower N−H bond dissociation enthalpy (BDE) than the recently reported bis(thiosemicarbazone) copper complex suggesting it could be a better antioxidant. In addition, the effect of different metals (Co, Fe, Pt, Ca, Ba, Sr, Au, Ag, Ni, and Zn) in their antiradical activity has been studied which suggests that among the studied metal complexes the Cu metal complex is the best metal complex for radical trapping. Further, the drug‐likeness is tested with the Lipinski filter along with the absorption, distribution, metabolism, and excretion (ADME) properties. Lastly, docking analysis tested against proteins responsible for ferroptosis shows that the modeled RTA can inhibit such diseases. Thus, it can be proposed that the designed RTA is a potential drug candidate.

Design of metallization layers for PZT piezoelectric ceramics and joining to 4J29 Kovar alloy

To enhance the bonding strength of PZT ceramics/4J29 Kovar alloy joints, the metallization layers on PZT ceramics were strategically designed, fabricated, and optimized. Subsequently, the metallized PZT ceramics were successfully joined with the 4J29 Kovar alloy using Sn-3.0Ag-0.5Cu (SAC305) solder. In this study, the wetting behavior, joining mechanism and the effect of metallization layers thickness on the joining strength were investigated. The (Ti + Ni + Au) multilayer structure enhances wetting, as Au dissolves into the solder to improve wetting, while Ni serves as a barrier to prevent direct contact between the solder and Ti, thereby ensuring the integrity of the metallization layer. The joining mechanism for PZT ceramics/solder and solder/4J29 Kovar alloy involves the reaction between Ni (in the metallization layer) and Sn (in the solder), and Sn diffusion into 4J29 Kovar alloy, respectively. The highest joint strength of 29.0±1.4 MPa was achieved with (Ti + Ni + Au) metallization layers (Ti:100 nm, Ni:1000 nm, Au:300 nm), marking a 120% improvement over the adhesive currently used for joining PZT ceramics to 4J29 Kovar alloy. Our work presents a promising method for joining PZT ceramics with 4J29 Kovar alloy, which is applied in transducers as a core component for oil logging.

Novel magnetic bimetallic AuCu catalyst for reduction of nitroarenes and degradation of organic dyes.

Herein, core-shell magnetic nanoparticles are modified with imidazolium-tagged phosphine and propylene glycol moieties and used for the stabilization of bimetallic AuCu nanoparticles. The structure and morphology of the prepared material are identified with SEM, TEM, XRD, XPS, atomic absorption spectroscopy, Fourier translation infrared spectroscopy, and a vibrating sample magnetometer. This hydrophilic magnetic bimetallic catalyst is applied in the reduction of toxic nitroarenes and reductive degradation of hazardous organic dyes such as methyl orange (MO), methyl red (MR), and rhodamine B (RhB), as well as in the degradation of tetracycline (TC). This magnetic AuCu catalyst indicated superior activity in all three mentioned reactions in comparison with its single metal Au and Cu analogs. This catalyst is recycled for 17 consecutive runs in the reduction of 4-nitrophenol to 4-aminophenol without a significant decrease in catalytic activity and recycled catalyst is characterized.

Interfacial bonding mechanisms of sintered Cu nanoparticles on different metallization surfaces

Cu nanoparticle sintering bonding is a low-cost die-attach method compared with Ag nanoparticles for power electronic packaging. The joint strength highly depends on the surface metallization of the devices. In present study, the interfacial sintering behavior of copper nanoparticle film (CNF) on different metallizations (Au, Ag, and Cu) was studied. The CNF exhibited a superior shear strength (115 MPa) on Cu substrates when sintered at 250 °C-15 MPa, much higher than that on Ag and Au metallized substrates. The interface connection ratio of bondline-substrate showed the same trend as the shear strength. The neck formation at the bonding interfaces showed no orientation preference. The lateral diffusion of Cu atoms on substrates dominated the sintering bonding, rather than the longitudinal diffusion. The Cu metallization showed much faster lateral diffusion than the Ag and Au metallization, which was confirmed by the neck growth of monolayer nanoparticle sintering and the molecular dynamics (MD) simulation.

Finite element analysis of thermal sensitivity of copper nanorods, nanoellipsoids, nanospheres and core-shells for hyperthermia application

Hyperthermia is a cancer treatment strategy that involves raising the temperature of the afflicted tissues without disrupting the surrounding tissues. This study is focused on finite element analysis of copper, nanoellipsoids, nanorods, nanospheres and core-shells for potential hyperthermia application. The temperature of copper nanostructures was elevated using an external source to the desired temperature to destroy the cancerous cell. The COMSOL Multiphysics package was used to calculate how long it would take to achieve the desired temperature using different nanostructures of copper. Thermal sensitivity of the tested nanostructures was checked by putting them in a spherical domain of tissue. It was observed that copper nano-rod attained the highest temperature of 43.3 °C compared to other geometries. It was also found that these geometries attained thermal equilibrium just after 0.5 μs. However, the copper nano-ellipsoid had a higher core volume, which is utilized to determine the thermal sensitivity of the nanostructures. Noble metal (Au) coating was first found to be better than PEG polymer coating for investigating core–shell structures. The Au coating on the surface of the copper core resulted in a gradual decrease in temperature with an increasing volume coverage ratio. These results conclude that copper nanostructures can be suitable candidates for hyperthermia.

NMR Spectroscopic Signatures of Cationic Surface Sites from Supported Coinage Metals Interacting with N-Heterocyclic Carbenes.

N-heterocyclic carbenes (NHCs) have been extensively studied to modulate the reactivity of molecular catalysts, colloids, and their supported analogues, being isolated sites, clusters, or nanoparticles. While the interaction of NHCs on metal surfaces has been discussed in great detail, showing specific coordination chemistry depending on the type of NHC ligands, much less is known when the metal is dispersed on oxide supports, as in heterogeneous catalysts. Herein, we study the interaction of NHC ligands with Au surface sites dispersed on silica, a nonreducible oxide support. We identify the easy formation of bis-NHC ligated Au(I) surface sites parallel to what is found on metallic Au surfaces. These species display a specific 13C NMR spectroscopic signature that clearly distinguishes them from the mono-NHC Au(I) surface sites or supported imidazoliums. We find that bis-ligated surface species are not unique to supported Au(I) species and are found for the corresponding Ag(I) and Cu(I) species, as well as for the isolobal surface silanols. Furthermore, the interaction of NHC ligand with silica-supported Au nanoparticles also yields bis-NHC ligated Au(I) surface sites, indicating that metal atoms can also be easily extracted from nanoparticles, further illustrating the dynamics of these systems and the overall favorable formation of such bis-ligated species across a range of systems, besides what has been found on crystalline metal facets.

Al2O3-Coated Bonding Wire with Electrical Insulation & Promoted Adhesion

Conventional bond wires composed of Au, Ag, & Cu don’t meet market demands for strong adhesion, electrical insulation, and corrosion passivation due to their conductive metallic surfaces. We propose a solution through the applications of a ceramic (Al2O3) coating at nanometer scales on these metal wires, thereby improving their adhesion to encapsulation, electrical insulation, and resistance to corrosion. We used ALD (Atomic Layer Deposition) methods to coat Au and Ag metal wires with diameters ranging from 18um to 48um (0.7mil~1.9mil) with Al2O3. Our paper details the innovative processes we used to incubate the idea of Al2O3 coating on conventional bond wires, focusing on wire bondability and dependability. Our findings demonstrate enhanced electrical insulation between crossing wires and increased reliability related to the wires’ adhesion to encapsulation.

Potentiating Immunogenic Cell Death in Cold Tumor with Functional Living Materials of FeAu-Methylene Blue Composites.

Low immunogenicity, absence of tumor-infiltrating lymphocytes and immunosuppressive microenvironment of immune cold tumors are the main bottlenecks leading to unfavorable prognosis. Here, an integrated tumor bioimaging and multimodal therapeutic strategy is developed, which converts immune cold into hot by modulating oxidative stress levels, enhancing photo-killing efficacy, inducing immunogenic cell death and inhibiting the immune checkpoint. On that occasion, the unique tumor microenvironment can be harnessed to biosynthesize in situ self-assembly iron complexes and fluorescent gold nanoclusters from metal ions Fe(II) and Au(III) for active targeting and real-time visualization of the tumors, simultaneously regulating reactive oxygen species levels within tumors via peroxidase-like activity. Furthermore, methylene blue (MB)-mediated photodynamic therapy promotes the release of damage-associated molecular patterns (DAMPs), which acts as in situ tumor vaccine and further induces dendritic cells maturation, augments the infiltration of antitumor T cells and significantly impedes the primary tumor growth and proliferation. More strikingly, by synergizing with the programmed cell death receptor-1 (PD-1) checkpoint inhibitor, the immunosuppressive microenvironment is remodeled and the survival time of model mice is prolonged. In summary, this paradigm utilizes the tumor-specific microenvironment to boost robust and durable systemic antitumor immunity, providing a novel opportunity for precision cancer theranostics.

Rapid Synthesis of Noble Metal Colloids by Plasma-Liquid Interactions.

The interactions between plasma and liquids cause complex physical and chemical reactions at the gas-liquid contact surface, producing numerous chemically active particles that can rapidly reduce noble metal ions. This study uses atmospheric-pressure surface dielectric barrier discharge (DBD) plasma to treat ethanol aqueous solutions containing noble metal precursors, and stable gold, platinum, and palladium colloids are obtained within a few minutes. To evaluate the mechanism of the reduction of noble metal precursors by atmospheric-pressure surface DBD plasma, the corresponding metal colloids are prepared first by activating an ethanol aqueous solution with plasma and then adding noble metal precursors. It is found that the long-lived active species hydrogen peroxide (H2O2) plays a dominant role in the synthesis process, which has distinct effects on different metal ions. When HAuCl4 and H2PdCl4 are used as precursors, H2O2 acts as a reducing agent, and AuCl4- and PdCl42- ions can be reduced to metallic Au and Pd. However, when AgNO3 is the precursor, H2O2 acts as an oxidising agent, and Ag+ ions cannot be reduced to obtain metal colloids because metallic Ag can be dissolved in H2O2 under acidic conditions. A similar phenomenon was also observed for the preparation of Pd colloid-PA with a plasma-activated ethanol aqueous solution using Pd(NO3)2 as a Pd precursor.

Advanced protein-embedded bimetallic nanocomposite optimized for in vivo fluorescence and magnetic resonance bimodal imaging

HypothesisThe development of bimodal imaging probes represents a hot topic of current research. Herein, we deal with developing an innovative bimodal contrast agent enabling fluorescence imaging (FI)/magnetic resonance imaging (MRI) and, simultaneously, consisting of biocompatible nanostructures. Optimized synthesis of advanced protein-embedded bimetallic (APEBM) nanocomposite containing luminescent gold nanoclusters (AuNC) and superparamagnetic iron oxide nanoparticles (SPION), suitable for in vivo dual-modal FI/MR imaging is reported. ExperimentsThe APEBM nanocomposite was prepared by a specific sequential one-pot green synthetic approach that is optimized to increase metals (Au, Fe) content and, consequently, the imaging ability of the resulting nanostructures. The protein matrix, represented by serum albumin, was intentionally chosen, and used since it creates an efficient protein corona for both types of optically/magnetically-susceptible nanostructures (AuNC, SPION) and ensures biocompatibility of the resulting APEBM nanocomposite although it contains elevated metal concentrations (approx. 1 mg·mL−1 of Au, around 0.3 mg·mL−1 of Fe). In vitro and in vivo imaging was performed. FindingsSuccessful in vivo FI and MRI recorded in healthy mice corroborated the applicability of the APEBM nanocomposite and, simultaneously, served as a proof of concept concerning the potential future exploitation of this new FI/MRI bimodal contrast agent in preclinical and clinical practice.

First‐Principles Study of Schottky Barrier Heights on Metal/4H‐SiC Polar Interfaces

4H‐SiC based devices have garnered significant interest within the realm of high‐voltage and high‐frequency electronic equipment. Schottky barrier heights (SBHs) play a pivotal role in determining the properties of metal/4H‐SiC contacts and holding significance for electrical performance of 4H‐SiC devices. Herein, the first‐principles method is utilized to investigate the interface properties between various metals (Sc, Mg, Zr, Ag, Al, Ru, Rh, Pd, Ni, Au, Ir, and Pt) and 4H‐SiC. The results reveal an approximate linear relationship between SBH and work function of these metals. Fermi‐level pinning factors are determined to be 0.27 and 0.32 for the Si‐face and C‐face interfaces, respectively. The disparity in pinning factors arises from polarization differences between the two interfaces, which stem from uneven net charge distribution on the Si‐face and C‐face. Meanwhile, the SBH values indicate a strong pinning effect, due to the charge transfer occurring at the metal/4H‐SiC interface. Through further analysis of layer density and differential charge density, the interatomic interaction and charge transfer between metal and SiC atoms are analyzed. This work offers fundamental insights into the structural changes in metal/4H‐SiC interfaces and provides valuable guidance in the potential prediction and optimization of device performance.