Amorphous Layer Research Articles

Enhancing cement hydration by core/shell PS@SiO2 nanoparticles

Nanoparticles are widely used in construction. Here, nano-SiO2 is employed, in a way that prevents agglomeration of the nanoparticles, as pozzolanic material to improve Portland cement hydration and to improve the properties of the concrete. To explore the effect of nano-SiO2 and core-shell PS@SiO2 on cement properties, spherical polystyrene particles were prepared by dispersion polymerization of styrene in polar solvents and characterized by FTIR and E-SEM. The core shells PS@SiO2 were synthesized by Stöber method. The results showed an amorphous nano-SiO2 layer can be deposited uniformly on polystyrene particles. This core/shell structure was reducing the aggregation of nano-SiO2 effectively. It was shown that PS@SiO2 particles improved the concrete performances compared to blended cement with nano-SiO2 due to the agglomeration affect. Highlights • Core/shell PS@SiO2 nanoparticles with a uniform coating layer were prepared. • As-prepared nanoparticles were characterized by a variety of advanced methods. • Nanoparticles accelerate hydration and lower the spatial weight of cement paste. • Core/shell nanoparticles improve cement hydration much better than nano-SiO2.

Amorphous nitrogen-doped carbon layers forming the interfacial channel for rapid charge transfer in ZnIn2S4/BiVO4 Z-scheme photocatalyst for enhancing organic pollutants degradation with simultaneous hydrogen evolution

Efficient photocatalytic hydrogen evolution from the organic wastewater represents an ideal solution for simultaneously addressing energy shortages and environmental pollution. However, the sluggish transport of photogenerated carriers at contact interface poses a key obstacle to enhancing photocatalytic activity. Here, ZnIn2S4/BiVO4@N-C (ZIS/BVO@N-C) Z-scheme photocatalysts were successfully constructed by a simple hydrothermal-impregnation method. ZIS/BVO@N-C-10% demonstrated outstanding photocatalytic performance, achieving a hydrogen evolution rate of 2695.68 μmol·g−1·h−1 and a degradation rate of 492.96 mmol·g−1·h−1 under visible light, surpassing those of ZIS (851.52 μmol·g−1·h−1 and 174.83 mmol·g−1·h−1) and ZIS/BVO-10% (1228.98 μmol·g−1·h−1 and 277.78 mmol·g−1·h−1). Characterization results and density functional theory (DFT) calculations revealed that the introduction of the N-C layer reduced interfacial impedance and enhanced the strength of interfacial electric field, overcoming the interfacial barrier and improving the photogenerated separation and migration efficiency at the interface, and ultimately enhancing the photocatalytic activity of ZIS/BVO@N-C. Based on experimental and characterization results, the photocatalytic mechanism of ZIS/BVO@N-C Z-scheme has been proposed. Furthermore, ZIS/BVO@N-C exhibited excellent stability, highlighting its potential for practical applications. This work also presents a new strategy for designing highly active Z-scheme photocatalysts for organic wastewater treatment and simultaneous hydrogen energy recovery.

Low-cost O2 plasma activation assisted direct bonding of β-Ga2O3 and Si substrates in air

This study presents a novel technique for directly bonding β-Ga2O3 and Si substrates using O2 plasma activation at room temperature. The activation process resulted in excellent surface hydrophilicity and roughness. Annealing in an N2 atmosphere revealed a bonding strength of 6.23 MPa, with partial fracture of the Si substrate. The bonding interface was observed by TEM and EDS. A distorted amorphous intermediate layer with a thickness of 100 nm and amorphous bubbles were observed in the bonding interface. In addition, the Ga, O, and Si elements were diffused and enriched, forming approximately 30 nm nodules at the bonding interface. This method offers a promising approach for integrating wide bandgap semiconductor materials in devices, bypassing the need for vacuum treatment.

Heterogeneous Ni-Boride/Phosphide Anchored Amorphous B-C Layer for Overall Water Electrocatalysis.

The rational design of efficient and economical bifunctional electrocatalysts remained a challenge for overall water electrolysis. In this work, the Ni-boride/ phosphide particles anchored amorphous B-doped carbon layer with hierarchical porous characteristics in Ni foam (Ni3P/Ni3B/B-C/NF) was fabricated for overall water splitting. The Boroncarbide (B4C) power was filled and fixed in the NF interspace through the electroplating and electroless plating, and then annealed in vacuum high temperature. The amorphous B-C layer derived from the B4 C not only speeded up the electron transport, but also cooperate with Ni-boride/phosphide to enhance the electrocatalytic activity for HER and OER synergistically. Furthermore, the hierarchical porous architecture of Ni3P/Ni3B/B-C/NF increased space utilization to load more active materials. The self-supported Ni3P/Ni3B/B-C/NF electrode possessed a low overpotential of 212 and 280 mV to deliver 100 mA cm-2 for HER and OER, respectively, and high stability for 48 h. In particular, the electrolyzer constituted with the Ni3P/Ni3B/B-C/NF bifunctional electrocatalyst only required a voltage of 1.59 V at 50 mA cm-2 for water electrocatalysis under alkaline medium, and demonstrated long-term stability for 48 h. This study provides a new technical path for the development of bifunctional of transition metal borides to promote the application of hydrogen production from water splitting.

Synthesis, characterisation and in vitro anticancer activity of conjugated protease inhibitor-silver nanoparticles (AgNPs-PI) against human breast MCF-7 and prostate PC-3 cancer cell lines.

The conjugated silver nanoparticles using biomolecules have attracted great attention of researchers because physical dimensions and surface chemistry play important roles in toxicity and biocompatibility of AgNPs. Hence, in the current study, synthesis of bio-conjugated AgNPs with protein protease inhibitor (PI) isolated from Streptomyces spp. is reported. UV-visible spectra of PI and AgNPs showed stronger peaks at 280 and 405nm, confirming the synthesis of conjugated AgNPs-PI. TEM and SEM images of AgNPs-PI showed spherical-shaped nanoparticles with a slight increase in particle size and thin amorphous layer around the surface of silver nanomaterial. Circular dichroism, FT-IR and fluorescence spectral studies confirmed AgNPs-PI conjugation. Conjugated AgNPs-PI showed excellent anticancer potential than AgNPs and protease inhibitor separately on human breast MCF-7 and prostate PC-3 cell lines. The findings revealed that surface modification of AgNPs with protein protease inhibitor stabilised the nanomaterial and increased its anticancer activity.

Analysis of the Structure of Heavy Ion Irradiated LaFeO3 Using Grazing Angle X-ray Absorption Spectroscopy.

Crystalline ceramics are candidate materials for the immobilization of radionuclides, particularly transuranics (such as U, Pu, and Am), arising from the nuclear fuel cycle. Due to the α-decay of transuranics and the associated recoil of the parent nucleus, crystalline materials may eventually be rendered amorphous through changes to the crystal lattice caused by these recoil events. Previous work has shown irradiation of titanate-based ceramics to change the local cation environment significantly, particularly in the case of Ti which was shown to change from 6- to 5-fold coordination. Here, this work expands the Ti-based study to investigate the behavior in Fe-based materials, using LaFeO3 as an example material. Irradiation was simulated by heavy ion implantation of the bulk LaFeO3 ceramic, with the resulting amorphous layer characterized with grazing angle X-ray absorption spectroscopy (GA-XAS). Insights into the Fe speciation changes exhibited by the amorphized surface layer were provided through quantitative analysis, including pre-edge analysis, and modeling of the extended X-ray absorption fine structure (EXAFS), of the GA-XAS data.

Surface topography and subsurface structure evolution in laser micro polishing of monocrystalline silicon

Ultra-smooth silicon surfaces, crucial in short-wave optics, can be marred by surface defects and subsurface damage incurred during machining, thereby affecting the imaging quality and transmission efficiency of optical components. Laser micro-polishing emerges as a versatile and efficient technique for ultra-precision polishing. This study aims to scrutinize the surface topography and subsurface structural evolution of monocrystalline silicon wafers during laser micro-polishing experimentally and to formulate an accessible evaluation model that incorporates multiple process parameters for optimal polishing results. As laser fluence escalates, the polishing process can be divided into six regimes: bulge, coalescence, smoothness, groove, ripple, and ablation. Each regime's crystal structure evolution is analyzed using Raman spectroscopy, demonstrating a close relationship with the surface expansion preceding the melting of monocrystalline silicon. Surface roughness diminishes from 6 nm to 0.7 nm, and an optimal crystalline quality devoid of an amorphous layer, residual stress, or significant subsurface damage is achieved. Amorphous silicon, 20 μm thick, is converted into monocrystalline silicon through recrystallization, and subsurface distortions and dislocations are rectified due to silicon atom redistribution. Moreover, a mapping relationship between multiple process parameters and surface polishing effects is established. A dimensionless fluence considering multiple parameters is derived, and a predictive model for process parameter optimization to secure optimal polishing results is proposed.

Strength and toughness of semicrystalline polymer fibers: Influence of molecular chain entanglement

The mechanical properties of oriented semicrystalline polymers fibers are mainly determined by the semicrystalline morphology in which lamellar crystals and disordered amorphous layers are in staggered arrangement. As a stress transmission channel, amorphous entanglement network can affect the strength and toughness of fiber together with crystalline phase. In this study, the relationship between mechanical properties and amorphous entanglement of oriented poly (l-lactic acid) fibers was clarified by studying the cyclic loading characteristics. Based on the Haward-Thakray model of semi-crystalline polymers, the energy contributions of the crystalline phase and the amorphous phase are separated. During the deformation of oriented fiber, the crystal will be broken under the action of tight entanglement network, and the entanglement network can transfer stress well without failure under the action of straight chain. Therefore, although the crystalline phase and the amorphous phase jointly bear the strength, the toughness and fracture behavior mainly affected by the entangled network of the amorphous phase.

Surface aspects of novel Bio-HEAs MAO-treated in a Ca-, P-, and Mg-rich electrolyte

This study evaluated the effect of alloying elements, applied voltage, and bioactive species (Ca, P, and Mg) enrichment during the micro-arc oxidation (MAO) treatment of novel high entropy alloys (HEAs) targeted for biomedical applications. The non-equiatomic TiZrNbTaMo (TaMo), TiZrNbTaMn (TaMn), and TiZrNbFeMo (FeMo) samples were submitted to MAO treatment at distinct voltages (100, 200, and 300 V), then their chemical, phase, and morphological aspects were evaluated by x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM and TEM). Finally, the preliminary physicochemical behavior regarding contact angle and surface energy in distilled water at room temperature was evaluated. The results indicated that the alloying elements played a global role in the bulk’s phase composition, possessing distinct proportions of BCC and HCP phases. The MAO-treated surfaces depicted different mechanisms of anodic oxide growth and dielectric breakdown, forming the typical porous surface at distinct applied voltages. The bioactive species (Ca, P, and Mg) were gradually enriched in the oxide layer, composed of distinct nano-crystalline and amorphous layers that are typical of MAO-treated surfaces. As a result, roughness, contact angle and surface energy values of the MAO-treated samples were affected by the applied voltage and the bulk’s chemical composition, indicating potential for use in the biomedical field, especially as long-term implants and bone fixation devices.

FeSiAl soft magnetic composite with double Al2O3 insulation layers for simultaneous high mechanical and magnetic properties

FeSiAl-based soft magnetic composites (SMCs), prepared from insulated FeSiAl powders, are widely applied in electronic devices. However, it is still challenging to achieve high magnetic and mechanical properties simultaneously due to the undesirable insulation layer. Here, double Al2O3 insulation layers are prepared for FeSiAl SMC. Atomic-scale characterizations reveal an in-situ epitaxial Al2O3 layer at FeSiAl surface under the catalysis of NaAlO2, and an outer amorphous Al2O3 layer by subsequent NaAlO2 hydrolysis. The above structure ensures effective insulation of FeSiAl powders and excellent magnetic properties of the FeSiAl/NaAlO2 SMC, with permeability of 101 and power loss of 128 mW/cm3 (50 mT, 100 kHz) respectively. Moreover, in-situ Al2O3/amorphous Al2O3 on FeSiAl matrix also leads to distinguished crush strength of 36.5 MPa for the core sample, which is ascribed to the enhanced adhesion at different interfaces as evidenced by similar local oxygen coordination and low strain distribution. This work provides a novel method to fabricate high-performance FeSiAl SMCs.

MnO@Mn2O3 Nanocrystals Embedded in Biochar Networks for Sustainable Anode of Lithium-ion Batteries

MnO is an alternative for commercial graphite as anode material for lithium-ion batteries (LIBs), if the issue of unstable performance caused by volume changes, poor conductivity, and changes in valence state of Mn is addressed. In this study, a series of nano MnO/biochar-containing composite materials were prepared with Mn(NO3)2, urea and pomelo peel as raw materials, via simple hydrothermal treatment and calcination, as anode materials for LIBs, where the biochar was used as inexpensive conductive medium and volume buffer. The electrochemical performance of the composite materials shows complicated correlation with the biochar contents, which associate with different carbonization temperatures. Elaborate characterizations with XRD, SEM, TEM, and Mn 2p, Mn 3s XPS spectra were conducted and jointly analyzed, which revealed that the surface of MnO nanocrystals undergoes different degrees of oxidation. The thickness of the surface amorphous Mn2O3 layer on the MnO nanocrystals influences the long-term electrochemical stability more significantly than the circumstances of biochar encapsulation, which was proved through cyclic voltammetry (CV) measurements. A composite material with moderate biochar content and thin layer of Mn2O3 coating on MnO nanocrystals will show more stable electrochemical performance. Based on this principle, one regulated composite material (MnOx/BC-650) gives an ultra-stable capacity of 446.9 mAh∙g−1 at 500 mA∙g−1 after 200 cycles. This study provides new insight for both revealing the true structure of manganese oxides and developing long-term stable MnO-containing anode materials for LIBs.

Zero Voltage-Degradation of Li2MnO3 with Ultrathin Amorphous Li─Mn─O Coating.

Manganese-based lithium-rich layered oxides (Mn-LLOs) are promising candidate cathode materials for lithium-ion batteries, however, the severe voltage decay during cycling is the most concern for their practical applications. Herein, an Mn-based composite nanostructure constructed Li2MnO3 (LMO@Li2MnO3) is developed via an ultrathin amorphous functional oxide LixMnOy coating at the grain surface. Due to the thin and universal LMO amorphous surface layer etched from the lithiation process by the high-concentration alkaline solution, the structural and interfacial stability of Li2MnO3 are enhanced apparently, showing the significantly improved voltage maintenance, cycle stability, and energy density. In particular, the LMO@Li2MnO3 cathode exhibits zero voltage decay over 200 cycles. Combining with ex situ spectroscopic and microscopic techniques, the Mn2+/4+ coexisted behavior of the amorphous LMO is revealed, which enables the stable electrochemistry of Li2MnO3. This work provides new possible routes for suppressing the voltage decay of Mn-LLOs by modifying with the composite functional unit construction.

Oxidation and mechanical properties of SiC fibers after high temperature exposure in air and steam

SiC fibers are widely used in composites exposed to high temperature oxidizing environments. The present study compares the oxidation behavior of SiC fibers and the associated changes in tensile strength upon their exposure to dry air and steam for up to 50 hours at temperatures from 950°C to 1350°C. In both cases, the scale thickness and oxide microstructure were analyzed by scanning electron microscopy. When the SiC fibers were oxidized in air, a crack-free amorphous oxide layer formed at temperatures up to 1200°C, whereas a cracked, crystallized oxide layer was found at 1350°C. By contrast under steam environment, a crystalline oxide forms at 950°C for oxidation times longer than 30 h. In both environments, the fiber strength decreased with increasing exposure time and temperature, the degradation being faster after oxidation in steam compared to dry air. This appears to relate to residual stress in the oxide scale and a reduction in the cross section of the load-bearing unoxidized SiC. An increase in defect size may also contribute to the loss of strength. The oxide scale follows parabolic growth kinetics in both dry air and in steam from 950°C to 1350°C, except at 1350°C for over 30 hours. The oxidation rate in steam is faster than that in dry air, with activation energies of 79.8±1.4 kJ/mol in steam and 153.6±3.4 kJ/mol in dry air, respectively. This work is relevant to the application of SiC fibers and SiC fiber reinforced composites in air and steam environments at high temperature.

Reststrahlen band infrared damping, microwave transparent AlN/polymeric film filters

The low-temperature (t ≈ 20–30 °C) technology of hybrid helicon-arc ion-plasma deposition to grow the amorphous AlN layers on polymeric substrates for getting the IR blocking filters was used. Flexible substrates based on Mylar, Polyethylene Terephthalate/BaSO4 filling and Teflon polymeric films were applied to grow the AlN layers having the Reststrahlen Band at λ∼11–17 μm for filters, which are damping the IR radiation in this spectral region. The Polyvinyl chloride polymeric films without coatings and the Mylar/AlN structures were used to make composed damping filters for spectral range λ∼7.5–25 μm. The transparency of such composed filters in the spectral range λ ∼7.5–25 μm can suppress about 96–98 % of radiation from the objects being at t ∼310 K. In this spectral range, the objects radiate ∼75 % of the total radiated power from a black body in the full EM band spectra. An explanation of the behavior's peculiarities of the spectral dependences of the IR reflectance of polymeric films/AlN structures with using the classical dielectric function model was proposed. The transparency of all polymeric/AlN structures in the microwave frequency range (ν = 60–270 GHz) gains T ≥ 80–90 %.

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.

Preparation of integrated carbon fiber stitched fabric reinforced (SiBCN) ceramic/resin double-layered composites for ablation resistance, thermal insulation and compression resistance performance

This paper reports a novel integrated carbon fiber fabric reinforced ceramic/resin double-layered composite. The composites were prepared by a low energy consumption process of stratified impregnate pyrolysis. The double-layered composites consist of an amorphous SiBCN ceramic upper layer and a SiBCN resin bottom layer. In the ablation experiment, the temperature of the composite material's ablated surface exceeded 1850 °C, while the temperature of the backside remained below 70 °C within 60 s of ablation. Even after 90 s of ablation, the backside temperature was still significantly lower than the theoretical application temperature of SiBCN resin. The ablated surface has no visible pits or cracks. The maximum mass ablation rate and line ablation rate were −0.01259 mg/s and 0.000933 mm/s, respectively. High-density amorphous SiBCN ceramic layer effectively play the role of high temperature and ablation resistance. In addition, the compressive strengths of the composites before and after ablation were above 340 MPa. Integrated composites that combine anti-ablation, insulation, and compression resistance have potential in aerospace applications.

Robust Self‐powered Optoelectronic Synapses Based on Epitaxial InSe/GaN Heterojunction with Interfacial Charge‐Trapping Layer

AbstractNeuromorphic devices that parallelize perception, preprocessing, and computation functions are expected to play a significant role in future non‐von Neumann architecture computers. Herein, a new retina‐inspired broadband self‐powered optoelectronic synaptic device based on 2D/3D heterojunction of epitaxial InSe on GaN(0001) is reported. Few‐layer n‐type InSe is grown on p‐type GaN by physical vapor deposition in an ultra‐high vacuum (UHV) environment. The devices are fabricated using a shadow mask assisted UHV electrode deposition technique. High‐resolution transmission electron microscopy images reveal that an atomically thin amorphous layer, which induces highly efficient charge trapping, is formed at the InSe/GaN interface. The photoresponse spans from visible to near‐infrared, and the response time is prolonged to 103 ms owing to the deep trapping levels. Thus, synaptic functions, including excitatory postsynaptic current, paired‐pulse facilitation with a high index of up to 170%, short‐term plasticity, and high‐pass filtering characteristics, are realized. Additionally, the synapses demonstrated the merit of realizing image sharpening and arithmetic operations on the same device under infrared and visible light illumination. This study provides a new platform of 2D/3D heterostructures for robust optoelectronic synapses that may find applications in post‐Moore era neuromorphic vision systems.

Effect of combined laser shock peening and nitrogen implantation on the microstructure and tribology of M50 bearing steel

The M50 bearing steel underwent a combined treatment of laser shock peening (LSP) and nitrogen ion implantation. The microstructure, surface mechanical properties and tribological behaviors were evaluated. Comparative analysis with the untreated sample revealed significant improvements in surface nano-hardness, increasing from 7.51 GPa to 11.35 GPa, 11.51 GPa, and 12.62 GPa for samples subjected to LSP, ion implantation, and combined strengthening, respectively. Correspondingly, surface compressive residual stress showed notable increases from −15.55 MPa to −1043.76 MPa, −451.34 MPa, and −1276.13 MPa, respectively. The improved surface mechanical properties observed in the combined strengthened sample are likely due to the synergistic effects of the combined strengthening. In friction tests, the combined strengthened sample exhibited the lowest friction coefficient, attributed to the presence of a metal nitride layer and a thicker amorphous layer. Wear mechanisms transitioned from fatigue spalling for the untreated specimen to slight wear and the formation of an oxidative adhesion layer after LSP and ion implantation. Remarkably, the surface of the combined strengthened specimen demonstrated minimal wear, with only an oxidative adhesion layer present.

Residual stress and subsurface damage in sapphire ultra-precision grinding

This study conducted experiments on ultra-precision grinding of sapphire using various strategies. It evaluated surface and subsurface characteristics across multiple dimensions, including morphology, scale, mechanical properties, residual stresses, lattice distortions, in-service properties, and chemical components. The research aimed to explore the intrinsic relationship between these behaviours. The findings revealed that both semi-finish grinding and ultra-precision grinding achieved ductile and low-roughness surfaces, with surface hardness enhancement near the grinding surface. Additionally, Raman spectra wave shifts were able to distinguish residual stresses at different grinding strategies, with larger stresses observed in ultra-precision grinding compared to semi-finish grinding and rough grinding. Furthermore, dense etching dislocation pits were observed on the ultra-precision grinding surface, responding to the scale of residual stress. The presence of larger subsurface cracks in semi-finish grinding and rough grinding was found to contribute to the release of residual stress. Moreover, ultra-precision grinding significantly reduced subsurface damage compared to rough grinding, with a reduction from 23.8 μm to 4.3 μm. Photothermal absorption during rough grinding was noted to be over 10 times higher than in ultra-precision grinding. Transmission electron microscopy (TEM) analysis revealed that subsurface damage included microcrack-induced line defects and uniform plastic deformation areas. This damage involved lattice aberrations, dislocations, stacking faults, and thin amorphous layers. The hardness and modulus of the subsurface damage layer were observed to decrease. Additionally, Raman spectra wave shifts were able to distinguish the subsurface damage layer in ultra-precision grinding. Energy-dispersive X-ray spectroscopy (EDS) analysis showed no change in the chemical components of the subsurface damage layer. Furthermore, a model was proposed to evaluate subsurface damage based on residual stress, and the mechanism of residual stress inducing damage in ultra-precision grinding was further analysed.

Impact of Amorphous LiF Coating Layers on Cathode‐Electrolyte Interfaces in Solid‐State Batteries

AbstractHigh interfacial resistance between electrodes and solid‐state electrolyte is the major cause for the failure of all‐solid‐state Li‐ion batteries. Spontaneous (electro)chemical reactions and poor Li‐ion diffusion at the interfaces are closely related to this increased impedance. Although introducing a coating layer can mitigate interfacial reactions and structural reconstruction, it may also lead to poor Li‐ion diffusion. Balancing this trade‐off therefore is crucial for the design of coating layer materials. In this study, the impact of the amorphous LiF (a‐LiF) coating layer on interfacial structural reconstruction and Li‐ion diffusion at the LiCoO2/Li6PS5Cl solid‐state interface is explicitly elucidated via machine‐learning‐assisted molecular dynamics (MD) simulations. It is found that the a‐LiF can effectively protect the P‐S tetrahedron local structures in Li6PS5Cl but cannot suppress the formation of side product S2 dimers. It is further discovered that once the a‐LiF coating exceeds a certain critical thickness, emergence of ordered local structures will inhibit Li‐ion diffusion. The simulations propose that the optimal thickness of the coating layer is around 1 nm. Overall, the work provides a microscopic understanding for effects of the a‐LiF coating layer on the structural and kinetic properties of cathode‐solid electrolyte interfaces and can guide the design of interfacial coating materials for solid‐state batteries.