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Elucidating the mechanical forces between two solid surfaces immersed in a communal liquid environment is crucial for understanding and controlling adhesion, friction, and electrochemistry in many technologies. Although traditional models can adequately describe long-range mechanical forces, they require substantial modifications in the nanometric region where electronic effects become important. A hybrid quantum–classical model is employed herein to investigate the separation-dependent disjoining pressure between two metal surfaces immersed in an electrolyte solution under potential control. We find that the pressure between surfaces transits from a long-range electrostatic interaction, attractive or repulsive depending on the charging conditions of surfaces, to a strong short-range van der Waals attraction and then an even strong Pauli repulsion due to the redistribution of electrons. The underlying mechanism of the transition, especially the attractive–repulsive one in the short-range region, is elucidated. This work contributes to the understanding of electrotunable friction and lubrication in a liquid environment. [ABSTRACT FROM AUTHOR]

Electronic friction and Langevin dynamics is a popular mixed quantum–classical method for simulating the nonadiabatic dynamics of molecules interacting with metal surfaces, as it can be computationally more efficient than fully quantum approaches. In this work, we extend the theory of electronic friction within the hierarchical equations of motion formalism to models with a position-dependent metal–molecule coupling. We show that the addition of a position-dependent metal–molecule coupling adds new contributions to the electronic friction and other forces, which are highly relevant for many physical processes. Our expressions for the electronic forces within the Langevin equation are valid both in and out of equilibrium and for molecular models containing strong interactions. We demonstrate the approach by applying it to different models of interest. [ABSTRACT FROM AUTHOR]

Reaction barriers for molecules dissociating on metal surfaces (as relevant to heterogeneous catalysis) are often difficult to predict accurately with density functional theory (DFT). Although the results obtained for several dissociative chemisorption reactions via DFT in the generalized gradient approximation (GGA), in meta-GGA, and for GGA exchange + van der Waals correlation scatter around the true reaction barrier, there is an entire class of dissociative chemisorption reactions for which GGA-type functionals collectively underestimate the reaction barrier. Little is known why GGA-DFT collectively fails in some cases and not in others, and we do not know whether other methods suffer from the same inconsistency. Here, we present barrier heights for dissociative chemisorption reactions obtained from the random phase approximation in the adiabatic-connection fluctuation-dissipation theorem (ACFDT-RPA) and from hybrid functionals with different amounts of exact exchange. By comparing the results obtained for the dissociative chemisorption reaction of H2 on Al(110) (where GGA-DFT collectively underestimates the barrier) and H2 on Cu(111) (where GGA-DFT scatters around the true barrier), we can gauge whether the inconsistent description of the systems persists for hybrid functionals and ACFDT-RPA. We find hybrid functionals to improve the relative description of the two systems, but to fall short of chemical accuracy. ACFDT-RPA improves the results further and leads to chemically accurate barriers for both systems. Together with an analysis of the density of states and the results from selected GGA, meta-GGA, and GGA exchange + van der Waals correlation functionals, these results allow us to discuss possible origins for the inconsistent behavior of GGA-based functionals for molecule–metal reaction barriers. [ABSTRACT FROM AUTHOR]

Solid–water interfaces are ubiquitous in nature and technology. In particular, technologies evolving in the green transition, such as electrocatalysis, heavily rely on the junction of an electrolyte and an electrode as a central part of the device. For the understanding of atomic-scale processes taking place at the electrolyte–electrode interface, density functional theory (DFT) has become the de facto standard. The validation of DFT's ability to simulate the interfacial solid/water interaction is crucial, and ideal simulation setups need to be identified in order to prevent avoidable systematic errors. Here, we develop a rigorous sampling protocol for benchmarking the adsorption/desorption energetics of water on metallic surfaces against experimental temperature programmed desorption, single crystal adsorption calorimetry, and thermal energy atom scattering. We screened DFT's quality on a series of transition metal surfaces, applying three of the most common exchange–correlation approximations: PBE-D3, RPBE-D3, and BEEF-vdW. We find that all three xc-functionals reflect the pseudo-zeroth order desorption of water rooted in the combination of attractive adsorbate–adsorbate interactions and their saturation at low and intermediate coverages, respectively. However, both RPBE-D3 and BEEF-vdW lead to more accurate water adsorption strengths, while PBE-D3 clearly overbinds near-surface water. We relate the variations in binding strength to specific variations in water–metal and water–water interactions, highlighting the structural consequences inherent in an uninformed choice of simulation parameters. Our study gives atomistic insight into water's complex adsorption equilibrium. Furthermore, it represents a guideline for future DFT-based simulations of solvated solid interfaces by providing an assessment of systematic errors in specific setups. [ABSTRACT FROM AUTHOR]

The orientation and rearrangement of water on a gold electrode significantly influences its physicochemical heterogeneous performance. Despite numerous experimental and theoretical studies aimed at uncovering the structural characteristics of interfacial water, the orientational behavior resulting from electrode-induced rearrangements remains a subject of ongoing debate. Here, we employed molecular dynamics simulations to investigate the adaptive structure and dynamics properties of interfacial water on Au(111) and Au(100) surfaces by considering a polarizable model for Au atoms in comparison with the non-polarizable model. Compared to the nonpolarizable systems, the polarization effect can enhance the interaction between water molecules and the gold surface. Unexpectedly, the rotational dynamics directly associated with the orientational behavior of water adjacent to the gold surface is accelerated, thereby reducing the hydrogen bond lifetime. The underlying mechanism for this anomalous phenomenon originates from the polarization effect, which induces the attraction of the positive hydrogen atoms to the surface by the negative image charge. This leads to a change in orientation that disrupts the hydrogen bonds in the first water layer and subsequently accelerates reorientation dynamics of water molecules adjacent to the gold surface. These results shed light on the intricate interplay between polarization effects and water molecule dynamics on metal surfaces, establishing the foundation for the rational regulation of the orientation of interfacial water. [ABSTRACT FROM AUTHOR]

Metals exhibit nonequilibrium electron and lattice subsystems at transient times following femtosecond laser excitation. In the past four decades, various optical spectroscopy and time-resolved diffraction methods have been used to study electron–phonon coupling and the effects of underlying dynamical processes. Here, we take advantage of the surface specificity of reflection ultrafast electron diffraction (UED) to examine the structural dynamics of photoexcited metal surfaces, which are apparently slower in recovery than predicted by thermal diffusion from the profile of absorbed energy. Fast diffusion of hot electrons is found to critically reduce surface excitation and affect the temporal dependence of the increased atomic motions on not only the ultrashort but also sub-nanosecond times. Whereas the two-temperature model with the accepted physical constants of platinum can reproduce the observed surface lattice dynamics, gold is found to exhibit appreciably larger-than-expected dynamic vibrational amplitudes of surface atoms while keeping the commonly used electron–phonon coupling constant. Such surface behavioral difference at transient times can be understood in the context of the different strengths of binding to surface atoms for the two metals. In addition, with the quantitative agreements between diffraction and theoretical results, we provide convincing evidence that surface structural dynamics can be reliably obtained by reflection UED even in the presence of laser-induced transient electric fields. [ABSTRACT FROM AUTHOR]

Surface-specific sum frequency generation vibrational spectroscopy is applied to study the molecular configuration of short-chain n-alkanethiol self-assembled monolayers (SAMs with n = 2–6) on the Au surface. For monolayers with n ≥ 3, the alkanethiols are upright-oriented, with the CH3 tilt angle varying between ∼33° and ∼46° in clear even–odd dependency. The ethanethiol monolayer (n = 2) is, however, found to exhibit a distinct lying-down configuration with a larger methyl tilt angle (67°–79°) and a smaller CH2 tilt angle (56°–68°). Such a unique configurational transition from n = 2 to n ≥ 3 discloses the steric effect owing to chain–chain interaction among neighboring molecules. Through density functional theory calculations, the transition is further confirmed to be energetically favorable for thiols on a defective reconstructed Au(111) surface but not on the pristine one. Our study highlights the roles of the chain–chain interaction and the substrate surface atomic structure when organizing SAMs, offering a strategic pathway for exploiting their applications. [ABSTRACT FROM AUTHOR]

A novel mixed quantum–classical approach to simulating nonadiabatic dynamics of molecules at metal surfaces is presented. The method combines the numerically exact hierarchical equations of motion approach for the quantum electronic degrees of freedom with Langevin dynamics for the classical degrees of freedom, namely, low-frequency vibrational modes within the molecule. The approach extends previous mixed quantum–classical methods based on Langevin equations to models containing strong electron–electron or quantum electronic–vibrational interactions, while maintaining a nonperturbative and non-Markovian treatment of the molecule–metal coupling. To demonstrate the approach, nonequilibrium transport observables are calculated for a molecular nanojunction containing strong interactions. [ABSTRACT FROM AUTHOR]

Many studies have investigated the mass outflows generated when a planar shock transits an imperfect ("defected") metal surface, where the defects are symmetric triangular or sinusoidal grooves. Yet a fundamental question remains unanswered: how does the quantity of outflow mass and its maximum velocity vary as a function of the groove cross-sectional aspect ratio? We identify two sets of missing experiments that must be addressed to answer the question. The aspect ratio (groove depth over width) is equivalently represented by θ , the cross-sectional half angle, or by η 0 k , the amplitude multiplied by an effective wavenumber. Low θ (high η 0 k) grooves comprise the first set of missing experiments, which are necessary to determine the validity of theoretical predictions of the nonlinear regime (η 0 k ≥ 1 , θ < 57.5 °). The second set of missing experiments are those in which the volume of the groove (or equivalently, the axial cross-sectional area) has been held constant as θ or η 0 k are varied. Such experiments are necessary to independently measure the effects of variations in groove volume and groove aspect ratio on the resulting jets. [ABSTRACT FROM AUTHOR]

In this work, spin transport in ferroelectric tunnel junctions with composite barriers and magnetic electrodes is investigated theoretically using spin-dependent screening theory. The shape of the insulator barrier and the electronic structure of the ferromagnetic electrode inevitably affect the spin transport properties. Interestingly, we find that when the Fermi level approaches the bottom of the minority-spin band of the electrode, an approximately ±100% bidirectional spin-filtering effect can be realized due to the included exchange potential with an appropriate electronic band structure of electrodes. Additionally, electrically induced magnetic reconstruction would occur on the electrode surface due to spin-dependent band bending. Our study significantly deepens the current understanding of spin-dependent screening on metal surfaces and at metal/ferroelectric interfaces and provides a feasible method for achieving the interface magnetoelectric effect. [ABSTRACT FROM AUTHOR]

Sc0.18Al0.82N/GaN with state-of-the-art x-ray diffraction figures of merit grown by metal modulated epitaxy under metal-rich conditions and a low substrate temperature of 400 °C is demonstrated to have improved crystalline order [250 arc sec for the (0002) reflection and 469 arc sec for the (10 1 ¯ 5)] compared to a previous state-of-the-art sample grown at a more conventional temperature of 650 °C. While both samples show a columnar structure, the higher substrate temperature sample has a good symmetric rocking curve (RC) of 229 arc sec, but unlike the lower temperature sample, the RC of the (10 1 ¯ 5) asymmetric reflection could not be measured, indicating a more columnar structure common among ScAlN films. Local lattice constant maps (LLCMs) from 4D-STEM depict abrupt strain relaxation within ∼2 nm from the ScAlN/GaN interface for the sample grown at Tsub = 400 °C. Since these LLCMs suggest a lattice mismatch in the a-lattice constant, and since the films show a sudden roughening, the composition for lattice match to GaN may be less than the accepted 18%–20% Sc, consistent with the average GaN lattice match from lattice constant values reported in the literature of 12%. Compared to traditional III-Nitrides, ScAlN films have substantially more screw and mixed-type threading dislocations, suggesting substantial shear forces that result in significant twist and distortion leading to orthorhombic diffraction patterns as viewed from plan-view TEM in the Tsub = 650 °C sample. These results offer the possibility of ScAlN integration into low-thermal-budget processes including CMOS but further indicate that structural understanding of ScAlN remains lacking. [ABSTRACT FROM AUTHOR]

The rates and pathways of chemical reactions at metal surfaces can be strongly influenced by energy dissipation due to the nonadiabatic excitation of metallic conduction electrons. The introduction of frictional forces to account for this dissipation has been quite successful in situations for which the nonadiabatic coupling is weak. However, in cases where nonadiabatic coupling is strong, such as when electron transfer occurs, the friction model is likely to break down. Ryabinkin and Izmaylov have proposed 2-state and 3-state alternatives to the friction model for introducing electronic dissipation in molecular dynamics simulations. Here, we examine their 2-state model using some simple examples of atom–surface scattering. We find that, with the addition of decoherence, the 2-state model can produce quite promising results. [ABSTRACT FROM AUTHOR]

Ion-induced electron emission (IIEE) is an important process whereby ions impinging on a material surface lead to net emission of electrons into the vacuum. While relevant for multiple applications, IIEE is a critical process of electric thruster (ET) operation and testing for space propulsion, and, as such, it must be carefully quantified for safe and reliable ET performance. IIEE is a complex physical phenomenon, which involves a number of ion-material and ion-electron processes, and is a complex function of ion mass, energy, and angle, as well as host material properties, such as mass and electronic structure. In this paper, we develop a discrete model of kinetic IIEE to gain a more accurate picture of the electric thruster chamber and facility material degradation processes. The model is based on three main developments: (i) the use of modern electronic and nuclear stopping databases, (ii) the use of the stopping and range of ions in matter to track all ion and recoil trajectories inside the target material, and (iii) the use of a scattering Monte Carlo approach to track the trajectories of all mobilized electrons from the point of first energy transfer until full thermalization or escape. This represents a substantial advantage in terms of physical accuracy over existing semi-analytical models commonly used to calculate kinetic IIEE. We apply the model to Ar, Kr, and Xe irradiation of W and Fe surfaces and calculate excitation spectra as a function of ion depth, energy, and angle of incidence. We also obtain minimum threshold ion energies for net nonzero yield for each ion species in both Fe and W and calculate full IIEE yields as a function of ion energy and incidence angle. Our results can be used to assess the effect of kinetic electron emission in models of full ET facility testing and operation. [ABSTRACT FROM AUTHOR]

The molecular dynamics with electronic friction (MDEF) approach can accurately describe nonadiabatic effects at metal surfaces in the weakly nonadiabatic limit. That being said, the MDEF approach treats nuclear motion classically such that the nuclear quantum effects are completely missing in the approach. To address this limitation, we combine Electronic Friction with Ring Polymer Molecular Dynamics (EF-RPMD). In particular, we apply the averaged electronic friction from the metal surface to the centroid mode of the ring polymer. We benchmark our approach against quantum dynamics to show that EF-RPMD can accurately capture zero-point energy as well as transition dynamics. In addition, we show that EF-RPMD can correctly predict the electronic transfer rate near metal surfaces in the tunneling limit as well as the barrier crossing limit. We expect that our approach will be very useful to study nonadiabatic dynamics near metal surfaces when nuclear quantum effects become essential. [ABSTRACT FROM AUTHOR]

The immobilization of Re(I) complexes onto metal oxide surfaces presents an elegant strategy to enhance their stability and reusability toward photocatalytic CO2 reduction. In this study, the photocatalytic performance of fac-[ClRe(CO)3(dcbH2)], where dcbH2 = 4,4′-dicarboxylic acid-2,2′-bipyridine, anchored onto the surface of 1%m/m CuO/Nb2O5 was investigated. Following adsorption, the turnover number for CO production (TONCO) in DMF/TEOA increased significantly, from ten in solution to 370 under visible light irradiation, surpassing the TONCO observed for the complex onto pristine Nb2O5 or CuO surfaces. The CuO/Nb2O5 heterostructure allows for efficient electron injection by the Re(I) center, promoting efficient charge separation. At same time CuO clusters introduce a new absorption band above 550 nm that contributes for the photoreduction of the reaction intermediates, leading to a more efficient CO evolution and minimization of side reactions. [ABSTRACT FROM AUTHOR]

Reliable nanoswitch operation requires low contact voltages and stable electrical contact resistance (E C R). Surface cleanliness is crucial to prevent nanomechanical switch failure, which can occur due to the presence of insulating adventitious hydrocarbon films. In situ O2 plasma cleaning is effective but oxidizes metal surfaces. Here, the noble metal Pt, which forms PtOx, is employed to form electrodes. Previous studies report on PtOx electrical resistivity, but the effects of PtOx evolution at contacting interfaces due to electrical and mechanical stimuli have not been explored. This study investigates the impact of PtOx on E C R at low contact voltages under hot switching, cold switching, and mechanical cycling conditions. An increase in E C R upon plasma cleaning indicates the presence of a resistive PtOx layer. After hot and cold switch cycling at applied voltages of 300 mV or less, a low stable E C R is achieved. A higher contact voltage accelerates E C R stabilization. The results are consistent with PtOx film volatilization, which is primarily due to Joule heating rather than mechanical rupture. This investigation advances the understanding of interface evolution in plasma-cleaned nanoswitches. [ABSTRACT FROM AUTHOR]

Fluorescent emitters are quenched near the surfaces of metals via rapid energy transfer to the metal, via surface plasmons, waveguide modes, and absorption. Commonly, this quenching is reduced by introducing a polymeric or dielectric spacer but requires large distances, at least a fraction of the wavelength, between the metal and chromophore. Using the classical theory for a dipole above a metal/dielectric substrate, we investigate the fluorescent yield for emitters above a wide range of metals and spacers. For metals with low loss and low plasma frequencies, a high index spacer is shown to be advantageous for obtaining higher fluorescent yield in an "island of emission" at finely tuned spacer thickness just 20–30 nm from the metal surface. For such metal–dielectric combinations, fluorophores can be placed surprisingly close to the metal surface while remaining significantly emissive. [ABSTRACT FROM AUTHOR]

Alkali halides are known to exhibit interface electronic states (IES) when deposited on metal surfaces with ultra-thin coverage. Here, we examine the IES formed by sub-monolayer RbI growth on Ag(111), which exhibits spatial variations in electronic structure in surprising contrast to the results previously obtained for other alkali halides. We find that this spatially dependent behavior can be qualitatively modeled by using a two-dimensional cosine potential commensurate with the moiré superstructure, where the IES is constructed from the well-known analytical solutions to the Mathieu equation. Our results indicate this potential is more corrugated than for similar potentials reported for other alkali halides, a result of substrate–adlayer charge transfer interactions that are stronger for RbI. This two-dimensional effective potential leads to anisotropy in the effective electron mass, in surprising contrast to previous results for other alkali halides, which report a single isotropic mass. [ABSTRACT FROM AUTHOR]

Ligand-decorated metal surfaces play a pivotal role in various areas of chemistry, particularly in selective catalysis. Molecular dynamics simulations at the molecular mechanics level of theory are best adapted to gain complementary insights to experiments regarding the structure and dynamics of such organic films. However, standard force fields tend to capture only weak physisorption interactions. This is inadequate for ligands that are strongly adsorbed such as carboxylates on metal surfaces. To address this limitation, we employ the Gaussian Lennard-Jones (GLJ) potential, which incorporates an attractive Gaussian potential between the surface and ligand atoms. Here, we develop this approach for the interaction between cobalt surfaces and carboxylate ligands. The accuracy of the GLJ approach is validated through the analysis of the interaction of oxygen with two distinct cobalt surfaces. The accuracy of this method reaches a root mean square deviation (RMSD) of about 3 kcal/mol across all probed configurations, which corresponds to a percentage error of roughly 4%. Application of the GLJ force field to the dynamics of the organic layer on these surfaces reveals how the ligand concentration influences the film order, and highlights differing mobility in the x and y directions, attributable to surface corrugation on Co(11 2 ̄ 0). GLJ is versatile, suitable for a broad range of metal/ligand systems, and can, subsequently, be utilized to study the organic film on the adsorption/desorption of reactants and products during a catalytic process. [ABSTRACT FROM AUTHOR]

The formation process of Pd-based bimetallic nanoparticles synthesized by co-sputtering is investigated by performing in situ morphological observation using resistive spectroscopy. The segregation of the metal with lower surface energy on the nanoparticle surface is observed, and it is found that the formation process of the alloy nanoparticles tends to be similar to that of the nanoparticles composed of the core metal even when the atomic fraction of the shell metal is higher than that of the core metal. The co-sputtering process is simulated by the molecular dynamics analysis, and the observed formation process is theoretically confirmed. [ABSTRACT FROM AUTHOR]

Micro–nano symbiotic superamphiphobic surfaces can prevent liquids from adhering to metal surfaces and, as a result, improve their corrosion resistance, self-cleaning performance, pollution resistance, and ice resistance. However, the fabrication of stable and controllable micro–nano symbiotic superamphiphobic structures on metal surfaces commonly used in industry remains a significant challenge. In this study, a laser-electrochemical hybrid subtractive–additive manufacturing method was proposed and developed for preparing copper superamphiphobic surfaces. Both experimental and fluid simulation studies were carried out. Utilizing this novel hybrid method, the controllable preparation of superamphiphobic micro–nano symbiotic structures was realized. The experimental results showed that the prepared surfaces had excellent superamphiphobic properties following subsequent modification with low surface energy substances. The contact angles of water droplets and oil droplets on the surface following electrodeposition treatment reached values of 161 ± 4° and 151 ± 4°, respectively, which showed that the prepared surface possessed perfect superamphiphobicity. Both the fabrication method and the test results provided useful insights for the preparation of stable and controllable superamphiphobic structures on metal surfaces in the future. [ABSTRACT FROM AUTHOR]

Standard thermoreflectance-based measurements have been routinely taken on thin metal transducer (Au or Al) deposited samples. This is based on the fundamental hypothesis that the reflectance change (ΔR/R) of the metal surface is directly and linearly related to the temperature change (ΔT), within a wide but finite temperature range (Trange). The quantitative study on Trange has been ignored for a long time, which would possibly cause severe measurement issues and impede the possible new applications that the thermoreflectance measurements are taken on new metals or even directly on non-metals. Here, we present an approach that combines multiple probe wavelengths' nanosecond transient thermoreflectance technique with a transient temperature rise model to study the linear relation. This method enables fast and accurate determination of the Trange and the proportional coefficient (commonly called the thermoreflectance coefficient, Cth). We studied the commonly used metal transducers (Au and Al) and found that Au illuminated at 532 nm has a considerably larger Trange (from room T to at least 225 °C), with respect to Al illuminated at 785 nm (room T to 150 °C). The linear relationships of uncommon Ni and Ti metals are valid from room temperature to ∼115 °C, illuminated at 785 and 660 nm, respectively. Non-linearity was observed for Al, Ni, and Ti metals when the temperature was elevated above the quantified Trange. This method enables a facile and reliable platform to characterize thermoreflectance properties and better understand the mechanism of thermoreflectance linear relationship. [ABSTRACT FROM AUTHOR]

In the previous study Wang and Dou [J. Chem. Phys. 158, 224109 (2023)], we have derived a Floquet classical master equation (FCME) to treat nonadiabatic dynamics near metal surfaces under Floquet engineering. We have also proposed a trajectory surface hopping algorithm to solve the FCME. In this study, we map the FCME into a Floquet Fokker–Planck equation in the limit of fast Floquet driving and fast electron motion as compared to nuclear motion. The Fokker–Planck equation is then being solved using Langevin dynamics with explicit friction and random force from the nonadiabatic effects of hybridized electrons and Floquet states. We benchmark the Floquet electronic friction dynamics against Floquet quantum master equation and Floquet surface hopping. We find that Floquet driving results in a violation of the second fluctuation–dissipation theorem, which further gives rise to heating effects. [ABSTRACT FROM AUTHOR]

Although the d-band center theory can well describe the interaction between gas molecules and transition metal surfaces, the detailed reaction process and specific adsorption conditions are unclear. Hence, in this work, we systematically studied the adsorption mechanism, adsorption conditions, and recovery time of NO and NO2 molecules on different transition metals (Cu, Ag, Au, Ni, Pd, Pt, Rh, Ru, Tc, Mo, Nb, and Zr) surfaces by first-principles. The results indicated that the charge transfers from the dz2, dxz, and dyz orbitals of substrate atoms to the HOMOs/LUMOs of NO and NO2. Moreover, we demonstrate that the interaction orbitals between the NO/NO2 and the metal atoms excellently correspond with the match of energy level and parity, and the maximum overlap of the orbital wave function. Interestingly, the excellent linear scaling between charge transfer and the d-band center, work function, and matrix element (V2ad) of metals has been confirmed. Specifically, the different recovery times of these systems at different temperatures were explored. Our results can provide a feasible way for exploring gas-sensitive materials in the experiments. [ABSTRACT FROM AUTHOR]

Chiral molecules have the potential for creating new magnetic devices by locally manipulating the magnetic properties of metallic surfaces. When chiral polypeptides chemisorb onto ferromagnets, they can induce magnetization locally by spin exchange interactions. However, direct imaging of surface magnetization changes induced by chiral molecules was not previously realized. Here, we use magneto-optical Kerr microscopy to image domains in thin films and show that chiral polypeptides strongly pin domains, increasing the coercive field locally. In our study, we also observe a rotation of the easy magnetic axis toward the out-of-plane, depending on the sample's domain size and the adsorption area. These findings show the potential of chiral molecules to control and manipulate magnetization and open new avenues for future research on the relationship between chirality and magnetization. [ABSTRACT FROM AUTHOR]

Hydrogen atom scattering on metal surfaces is investigated based on a simplified Newns–Anderson model. Both the nuclear and electronic degrees of freedom are treated quantum mechanically. By partitioning all the surface electronic states as the bath, the hierarchical equations of motion method for the fermionic bath is employed to simulate the scattering dynamics. It is found that, with a reasonable set of parameters, the main features of the recent experimental studies of hydrogen atom scattering on metal surfaces can be reproduced. Vibrational states on the chemisorption state whose energies are close to the incident energy are found to play an important role, and the scattering process is dominated by a single-pass electronic transition forth and back between the diabatic physisorption and chemisorption states. Further study on the effects of the atom-surface coupling strength reveals that, upon increasing the atom-surface coupling strength, the scattering mechanism changes from typical nonadiabatic transitions to dynamics in the electronic friction regime. [ABSTRACT FROM AUTHOR]

The secondary electron spectrum (SES) contains complex surface information and is widely used in surface analysis technology. A theoretical model of the SES for metals was proposed to reveal the effect of the surface potential barrier on the SES. In our model, an improved inner secondary electron energy distribution was established according to the free electron gas model. The transmission coefficient of inner secondary electrons was determined by solving the density of electronic states. Finally, the model was verified by our experiments, and the effects of the coverage fraction and potential barrier height, width, and form on the SES were comprehensively analyzed. The results show that H2O adsorption lowers the barrier height and enhances the tunneling effect, resulting in the most probable energy shifting toward the low-energy end and full width at half maximum narrowing. In addition, increasing or broadening the barrier can weaken the secondary electron tunneling effect, reduce the secondary electron number, and increase the most probable energy and the full width at half maximum. The model in this paper provides a reliable analysis method for studying the SES under different surface barriers for metals. Relevant results have significant value for the analysis of scanning electron microscopy images and optimization of secondary electron detection systems. [ABSTRACT FROM AUTHOR]

Surface chemistry of MXenes is of great interest as the terminations can define the intrinsic properties of this family of materials. The diverse and tunable terminations also distinguish MXenes from many other 2D materials. Conventional fluoride‐containing reagents etching approaches resulted in MXenes with mixed fluoro‐, oxo‐, and hydroxyl surface groups. The relatively strong chemical bonding of MXenes' surface metal atoms with oxygen and fluorine makes post‐synthetic covalent surface modifications of such MXenes unfavorable. In this minireview, we focus on the recent advances in MXenes with uniform surface terminations. Unconventional methods, including Lewis acidic molten salt etching (LAMS) and bottom‐up direct synthesis, have been proven successful in producing halide‐terminated MXenes. These synthetic strategies have opened new possibilities for MXenes because weaker surface chemical bonds in halide‐terminated MXenes facilitate post‐synthetic covalent surface modifications. Both computational and experimental results on surface termination‐dependent properties are summarized and discussed. Finally, we offer our perspective on the opportunities and challenges in this exciting research field. [ABSTRACT FROM AUTHOR]

This study designs a metal surface movable-microwave heating cavity with a turntable to choose an efficient and uniform microwave heating method according to the shape of the ceramic. The movement of the metal surface affects the standing wave in the cavity, causing the electric field in the cavity to change constantly during heating due to the rotating turntable and metal surface motion. This results in the absorption mode of ceramic is not constant. However, it is challenging to mesh the dynamic position of ceramic; therefore, this study proposes a transform optics method to simulate the rotating motion of the turntable and the moving motion of the metal surface. Experiments verify the correctness of the simulation model. The heating effects of fixed heating, turntable rotating and metal surface moving are compared. Finally, the effects of microwave heating on ceramics at different speeds and moving rates are discussed. [ABSTRACT FROM AUTHOR]

The rapidly growing electroplating industry has led to the discharge of large amounts of wastewater containing heavy metals and organic acids. Innovative techniques are required for the efficient and effective treatment of such effluents. The present work explored electroplating wastewater treatment through new TiO2-NTs/GO/SnO2 electrodes by electro-oxidation (EO) in batch and once-through continuous system. A new electrode with excellent oxidation ability was successfully fabricated by introducing a SnO2 outer layer through a simple anodization method. Moreover, a response surface methodology (RSM)-Box-Behnken design (BBD) model was used to optimize the responses. The effects of operating conditions, i.e. pH (3–9), current (0.1–0.9 A), and time (30–180 min), on the efficiency of the process were investigated. With optimum conditions, 97.1% Cu, 95.7% Zn, 91.2% COD degradation, and 7.32 kWh/m3 energy consumption were achieved. A once-through continuous setup working at a flow rate of 5–20 mL/min was performed under optimal conditions. The electrodes remained durable even after 50 cycles. The contribution of several reactive species to the EO was examined in the presence of scavengers. Moreover, according to a toxicity study, EO can detoxify electroplating effluents. Hence, this EO process, which is low-cost and highly efficient, can be applied to the treatment of electroplating wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • NH 4 PF 6 dual beneficial role, hinders the dendritic growth and accelerate the SEI formation. • Stable lithium deposition stripping over 1500 cycles. • Operando confocal Raman spectroscopy demonstrates the electrolyte degradation in forming the SEI. Lithium-ion batteries (LiBs) with graphite as an anode and lithiated transition metal oxide as a cathode are approaching their specific energy and power theoretical values. To overcome the limitations of LiBs, lithium metal anode with high specific capacity and low negative redox potential is necessary. However, practical application in rechargeable cells is hindered by uncontrolled lithium deposition manifesting, for instance, as Li dendrite growth which can cause formation of dead Li, short circuits and cell failure. The electrochemical behaviour of a protic additive (NH 4 PF 6) in a carbonate-based electrolyte has been investigated by operando confocal Raman spectroscopy, in situ optical microscopy, and X-ray photoelectron spectroscopy, elucidating its functional mechanism. The ammonium cation promotes a chemical modification of the lithium metal anode-electrolyte interphase by producing an N -rich solid electrolyte interphase and chemically modifying the lithium surface morphology by electrochemical pitting. This novel method results in stable lithium deposition and stripping by a decreasing the local current density on the electrode, thus limiting dendritic deposition. [ABSTRACT FROM AUTHOR]

A temperature measurement system with a reflected laser beam that does not require temperature modulation was developed for the thermal design of electronic devices. The system combines a balanced photodetector and lock-in amplifier to make reflectance change measurements possible with an extremely high signal-to-noise ratio. First, to evaluate the accuracy of the reflectance change measurement, the reflectance change of a Ni thin film temperature-controlled by a heater and thermocouples was measured as a function of temperature change. To evaluate the accuracy of the temperature change measurement, the reflectance change was measured by heating a Ni thin film that imitated the wiring pattern of an electronic circuit. The experimental results showed that the standard deviation of the ratio of reflectance change from the reference reflectance was <1.00 × 10−5 at a constant temperature. Moreover, the error margin of the calculated temperature change was ±1.0% for a change of 22 °C or more from the reference temperature, and the performance was sufficient for the estimation of local temperature. [ABSTRACT FROM AUTHOR]

The Au/TiO 2 model catalyst has been extensively studied across various applications, yet its utilization in electrochemical CO 2 and CO reduction (EC CO 2 R and COR) remains underexplored. In this study, we employed the Au/TiO 2 /Ti system, prepared via a two-step process: initially forming rutile TiO 2 on metallic Ti through laser-assisted methods, followed by sputtering Au onto the surface. The experimental conditions included varying concentrations of KHCO 3 and phosphate, applied potentials, Au overlayer thickness, and laser treatment parameters for the Ti-based catalysts. The major products detected were syngas (CO and H 2), which varied with experimental settings, along with liquid formate and other hydrocarbons. The study also examined the role of surface species like *CO and H* in facilitating C–C coupling, drawing parallels to traditional Fischer-Tropsch (F-T) synthesis. Spectroscopic analyses, including XPS and UPS, were utilized to investigate interfacial electronic structures, oxidation states, and overlayer stability post-electrochemical processing. This research contributes to a deeper understanding of EC CO 2 R and COR mechanisms on Au/Ti electrodes, providing valuable insights into optimizing electrode design and operational conditions for enhanced catalytic efficiency in syngas production and direct F-T chemistry. [Display omitted] • Au/TiO 2 /Ti system was prepared by laser-assisting TiO 2 formation on Ti, followed by sputtering Au. • A tunable H 2 /CO ratio was by varying electrolyte concentrations and applied potentials in electrochemical CO 2 reduction. • Fischer-Tropsch synthesis pathway was understood through the role of *CO and H* in facilitating C–C coupling. • XPS and UPS revealed the oxidation states, interfacial electronic structures, and stability of Au overlayer. [ABSTRACT FROM AUTHOR]

Common half-cell measurements deliver oxygen reduction activities linked to the chosen scan rate, limiting their value for fundamental and comparative studies on platinum. Here we show a deconvolution of the intrinsic kinetics from the effect of surface oxygen on platinum. We find an electronic effect of the surface oxygen, substantiate a Tafel slope of ~120 mV/decade, obtain an exchange current density of 13 ± 4 µA/cm2, and an activity of 7 mA/cm2 at 900 mV. Eventually, we broaden the scope of this analysis to the effects of surface rearrangement, alloying, and supported Pt nanoparticles, the latter providing insight into discrepancies between half-cell and fuel cell measurements. We find through computational methods that binding energies of intermediates would be weakened by the presence of highly coordinated oxygen atoms. Finally, we obtain a phenomenological rate equation for the oxygen reduction and evolution reaction, suggesting that both reactions follow a shared mechanism. Catalyzing the splitting and formation of oxygen on noble metal surfaces are key reactions developing materials for electrolysis. Here, authors show on platinum that the state of a surface oxidation process is a key descriptor for the kinetics. [ABSTRACT FROM AUTHOR]

Metasurface structures have proven to be effective in enhancing terahertz sensing signals and can thus be used as sensors to improve terahertz detection sensitivity. However, the sensitivity is limited by the poor spatial overlap between the analytes and the local electric field of the metasurface. In this work, a novel design of a floating bilayer metasurface structure for terahertz sensing is proposed and investigated. This structure supports a sharp toroidal dipole resonance and can concentrate near‐field energy on the analyte and metal atoms rather than on the substrate surface by floating the metal atoms. Consequently, the sensitivity is significantly improved to as high as 362 GHz RIU−1; theoretically, this is approximately 2.6 times higher than that of the common metasurface. The ability of the floating bilayer metasurface to quantitatively detect chlorothalonil is experimentally demonstrated. The resonance peak shows a significant frequency shift of 7 GHz for a change of 0.0001 mg dL−1 in chlorothalonil concentration, reaching up to 86 GHz when the change in chlorothalonil concentration is 100 mg dL−1; this is approximately 6.6 times higher than that of the common metasurface. This work provides opportunities for metasurface to realize ultrasensitive sensing in the terahertz regime. [ABSTRACT FROM AUTHOR]

We experimentally demonstrate the broadband and highly efficient inversion of the rotation direction of the terahertz circular polarization achieved by a dynamic metasurface with vanadium dioxide ( VO 2 ). This metasurface converts linear polarization into circular polarization. The rotational direction of the output circular polarization can be reversed based on the VO 2 phase transition. The VO 2 state can be dynamically switched by injecting direct current into an on-chip circuit. To improve the terahertz-wave utilization efficiency, the metasurface is operated at an incident angle of 45°, thereby eliminating the beam splitter typically used to separate the outgoing wave from the incident wave at normal incidence. To achieve broadband operation, we employ a dispersion-cancelation strategy that cancels the dispersive phase responses between orthogonal linear polarizations. This strategy was previously developed for static metasurfaces; we have applied it to the design of dynamic metasurfaces. At a center frequency of 0.99 THz, the experimental evaluation demonstrated helicity switching with conversion efficiencies of 92% and 87% for the insulating and metallic states of VO 2 , respectively. Dispersion cancelation is simultaneously achieved for the insulating and metallic states of VO 2 , resulting in a relative bandwidth of 0.26, which is 3.2 times broader than that of a previously developed efficient dynamic metasurface. [ABSTRACT FROM AUTHOR]

Bay ecosystems with unique economic and ecological value are more vulnerable to heavy metal pollution than other marine ecosystems. In South Korea, rapid economic development has exacerbated heavy metal pollution in bay environments. This study analyzed concentrations of seven heavy metals and the structure of macrobenthic community in Asan Bay. Five heavy metal indices (PLI, Pn, RI, TRI, and MERMQ) were used to assess ecological risk. Additionally, spearman correlation, biota--environment matching (BIO-ENV), and redundancy analysis (RDA) were utilized to determine the influence of heavy metals on macrobenthic communities. Although average concentrations of seven heavy metals were below sediment quality guidelines (SQGs), the average concentration of Cd was close to the threshold effects level (TEL). The nemerow pollution index (Pn) and the potential ecological risk index (RI) indicated that Cd was the primary heavy metal contributing to ecological risk. Spearman correlation, BIO-ENV, and RDA indicated that heavy metals were the main environmental factors influencing macrobenthic communities in Asan Bay. However, five heavy metal indices (PLI, Pn, RI, TRI, and MERMQ) did not show a response to the macrobenthic communities. Overall, low concentrations of heavy metals have a certain negative impact on macrobenthic communities in Asan Bay. This study can serve as an important reference for marine environmental protection and policy-making in Asan Bay. [ABSTRACT FROM AUTHOR]

Due to coastal development expansion, an increasing influx of pollutants enters the sea through riverine input and land runoff, threatening coastal ecosystems and posing a risk of eutrophication. In this study, trace metals (Fe, Mn, Cu, and Zn), and nutrients (constituents of N, P, and Si) were assessed in the summer surface seawater of Yantai Sishili Bay (YSB), Northern China focusing on the determination of concentration, spatial-temporal distribution and sources identification, while exploring their correlations. It also aimed to clarify the eutrophication status and evaluate the linear relationships between eutrophication, trace metals, and nutrients in YSB. Over three years (2021-2023), the total dissolved concentrations of Fe, Mn, Cu, and Zn ranged from 4.79-26.71, 0.19-6.41, 0.26-1.53, and 0.74-13.12 µg/L, respectively. Concurrently, nutrient concentrations including NO2-, NO3-, NH4+, PO43-, and DSi exhibited a range of 0.37-11.66, 2.04-178.30, 1.69-70.01, 0.02-16.68, and 0.02-0.71 µg/L respectively. These concentrations revealed a gradual decrease from nearshore to offshore and the temporal variation also showed significant patterns from year to year, indicating distinct regional variations. The primary contributors to the trace metals and nutrients in the study region were recognized as external contributions stemming from natural, anthropogenic, and atmospheric deposition through correlation and principal component analysis. More specifically, riverine input and coastal farming contributed large amounts of nutrients to coastal waters, threatening a potential risk of eutrophication. The eutrophication evaluation expressed below the mild eutrophication level and was far lower than the other global and Chinese bays. The linear correlation between eutrophication and trace metals revealed a weak positive correlation but a significant correlation with nutrients. Despite the absence of significant eutrophication in the bay, potential risks were identified due to identifiable sources of nutrient and trace metal inputs. The findings provided insights to guide efforts in preventing and mitigating coastal eutrophication, as well as nutrient and trace metal pollution, in coastal cities. [ABSTRACT FROM AUTHOR]

Metal oxide films are essential in most electronic devices, yet they are typically deposited at elevated temperatures by using slow, vacuum-based processes. We printed native oxide films over large areas at ambient conditions by moving a molten metal meniscus across a target substrate. The oxide gently separates from the metal through fluid instabilities that occur in the meniscus, leading to uniform films free of liquid residue. The printed oxide has a metallic interlayer that renders the films highly conductive. The metallic character of the printed films promotes wetting of trace amounts of evaporated gold that would otherwise form disconnected islands on conventional oxide surfaces. The resulting ultrathin (<10 nanometers) conductors can be patterned into flexible circuits that are transparent, mechanically robust, and electrically stable, even at elevated temperatures. [ABSTRACT FROM AUTHOR]

Nowadays, biodegradable metals and alloys, as well as their corrosion behavior, are of particular interest. The corrosion process of metals and alloys under various harsh conditions can be studied via the investigation of corrosion atom adsorption on metal surfaces. This can be performed using density functional theory-based simulations. Importantly, comprehensive analytical data obtained in simulations including parameters such as adsorption energy, the amount of charge transferred, atomic coordinates, etc., can be utilized in machine learning models to predict corrosion behavior, adsorption ability, catalytic activity, etc., of metals and alloys. In this work, data on the corrosion indicators of Zn surfaces in Cl-, S-, and O-rich harsh environments are collected. A dataset containing adsorption height, adsorption energy, partial density of states, work function values, and electronic charges of individual atoms is presented. In addition, based on these corrosion descriptors, it is found that a Cl-rich environment is less harmful for different Zn surfaces compared to an O-rich environment, and more harmful compared to a S-rich environment. [ABSTRACT FROM AUTHOR]

In this paper, a new scheme for generating a wide gamut of structural colors on the thin‐film‐stack‐based (TFSB) substrates is proposed. The TFSB surfaces consist of titanium/random gold nanoparticles (AuNPs) and titanium/ random gold and copper nanoparticles (Au+CuNPs), which can trigger more resonance absorption and widen the color gamut. The electric fields in two designed structures are simulated, and the results showed that the random distribution of AuNPs and Au+CuNPs enhance the uniform local surface plasmon resonance (LSPR) response. This enhancement is crucial in broadening the coverage of the reflection spectrum, which enables the generation of a wide range of colors, including green and red. The influence of laser parameters on the color of TFSB substrates and tested their durability in terms of time is analyzed. Finally, a color palette and made structural color patterns on TFSB by nanosecond pulsed laser are prepared. The proposed new scheme can be easily fabricated by magnetron sputtering without requiring additional procedures, which can open new perspectives in plasmonic colors. This work demonstrates that the promising potential of methods in creating a wide color gamut on metallic surfaces. Additionally, it serves as a means to store information for the preservation and protection of traditional cultures. [ABSTRACT FROM AUTHOR]

Fouling of heat exchangers in the chemical industry, oil & gas industry, district heating, power plants, among others, results in a loss of performance which leads to production stops for cleaning and therefore increased operation costs. One approach to mitigate fouling is to alter the properties of the metal surface. A coating to be successful in any plate heat exchanger (PHE) application needs to have a good adhesion to the metal but also keep the heat transfer through the metal plates as unaltered as possible. This requires a thin coating with a relatively good thermal conductivity. The plates in a PHE are subjected to plate-to-plate contact point wear when in operation which also puts an extra requirement for the coating. To be suitable, the coating needs to have a good mechanical stability to resist this plate-to-plate wear. Alfa Laval has a long experience in coating plates for diverse applications and in this paper two case studies will be presented. One in the paper industry and the other in the biofuel industry. A new type of multilayer Teflon™ coating from Chemours was used, specifically designed to show excellent fouling release properties along with limited thicknesses (30–50 microns). [ABSTRACT FROM AUTHOR]

Thick and dense graphite anodes used in lithium‐ion batteries (LIBs) suffer from sluggish reaction kinetics at the electrode level, causing Li metal plating on their surfaces and significant capacity decay at high charging currents. Thus, it is crucial to tailor electrodes based on a comprehensive understanding of the complex reaction kinetics to realize fast‐charging LIBs. A multi‐interface strategy is proposed for electrode tailoring using Al2O3 nanoparticles to enhance fast‐charging capability while suppressing Li metal plating. Molecular dynamics simulations suggest that the incorporated Al2O3 nanoparticles perturb the charge and molecule distributions in the boundary layer, forming an "interfacial highway" for facile Li+ transport at the Al2O3/electrolyte interface. This pushes Li+ deeper into the electrode and homogenizes the Li+ flux across the electrode's top surface. A full cell assembled with the Al2O3‐decorated graphite electrode (areal capacity of 4.4 mAh cm−2) exhibits excellent cyclability with a capacity retention of 83.4% over 500 cycles even at a 2C rate without any noticeable signal for undesirable Li plating. The role of interfacial highways predicted by theoretical computations is further validated using a pouch‐type full cell (500 mAh). These findings provide insights into the interfacial and microstructural design of high‐capacity graphite electrodes for fast‐charging, long‐cycling LIBs. [ABSTRACT FROM AUTHOR]

Corrosion poses a significant challenge, causing severe damage to steel infrastructures across various industries, particularly those involved in delivering fossil fuel sources. The present study introduces an innovative approach to the development of corrosion inhibitors through the synthesis of a zinc nanoparticle (Zn NP) and polystyrene (PS) composite (ZnNPs@PS composite). The synthesized composite was characterized, revealing a surface area (SBET) of 33.62 m2 g−1 and an average pore diameter (Dp) of 9 nm. The analysis was conducted using several techniques including Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, and transmission electron microscopy (TEM). The successful immobilization of Zn NPs, with an average size range of 4–50 nm, within the PS matrix was confirmed. The composite's corrosion inhibition efficiency (CIE) was evaluated using the weight loss method. Treated steel samples, after immersion in formation water, diesel fuel, and sulfuric acid (H2SO4) for 10 days at 25 °C, demonstrated CIE percentages of 94.27%, 88.18%, and 85.05%, respectively. This novel composite thus shows promising potential as an effective corrosion inhibitor for steel in various corrosive environments. [ABSTRACT FROM AUTHOR]

Li metal batteries with polymer electrolyte are of great interest for next-generation batteries for high safety and high energy density. However, uneven deposition on the lithium metal surface can greatly affect battery life. Therefore, surface modification on the Li metal become necessary to achieve good performance. Herein, an artificial solid electrolyte interface (SEI) modified lithium metal anode is prepared using cation-polymerization process, as triggered by PF5 generated from CsPF6. As a result, the polarization voltage of Li||Li symmetric battery assembled with artificial SEI-modified Li metal anode was stable with a small over-potential of 25 mV after 3000 h at current density of 1.5 mA cm−2. Electrochemical performance of Li||NCM 622 (LiNi0.6Co0.2Mn0.2O2) full cell with soft-matter polymer electrolyte is significantly improved than bare Li-metal, the capacity retention is 75% after 120 cycles with N/P = 3:1 at a cut-off voltage of 4.3 V. Our work has shed lights on the commercialization of Li metal battery with polymer electrolyte. [ABSTRACT FROM AUTHOR]

Corrosion worldwide causes large losses of metal, which is why various ways are being sought to slow it down. The aim of this study was to investigate the inhibitory effect of fennel fruit essential oil (Foeniculum vulgare Mill.) and its main component anethole. The inhibitory effect of three different concentrations of the fennel essential oil and anethole (1.0 mL/L, 1.5 mL/L, and 2.5 mL/L) in a solution of 1 M HCl at 298 K for 6 h on a sheet of low-carbon steel was investigated. The inhibitory effect was established using gravimetric methods evaluating weight loss, corrosion rate, and inhibition efficiency, as well as electrochemical methods. In gravimetric studies, the inhibition effect of the inhibitors fennel essential oil and isolate anethole at a concentration of 2.0 mL/L was 70.85% and 45.86%, respectively. The anodic polarization curve data at 298 K demonstrate that the anethole and fennel essential oil adsorption on the metal surface creates a barrier that hinders hydrogen ions' access and prevents them from being reduced on the steel surface's cathode sites. Fennel essential oil acting as a mixed type-inhibitor can replace synthetic organic substances and could become an alternative to be used as environmental corrosion inhibitors. [ABSTRACT FROM AUTHOR]

In this work, we enhanced the U-shaped network and proposed a method for detecting scratches on metal surfaces based on the Metal Surface Defect Detection U-Net (MSDD-UNet). Initially, we integrated a downsampling approach using a Space-To-Depth module and a lightweight channel attention module to address the loss of contextual information in feature maps that results from multiple convolution and pooling operations. Building on this, we developed an improved attention module that utilizes image frequency decomposition and cross-channel self-attention mechanisms, as well as the strengths of convolutional encoders and self-attention blocks. Additionally, this attention module was integrated into the skip connections between the encoder and decoder. The purpose was to capture dense contextual information, highlight small and fine target areas, and assist in localizing micro and fine scratch defects. In response to the severe foreground–background class imbalance in scratch images, a hybrid loss function combining focal loss and D i c e loss was put forward to train the model for precise scratch segmentation. Finally, experiments were conducted on two surface defect datasets. The results reveal that our proposed method is more advantageous than other state-of-the-art scratch segmentation methods. [ABSTRACT FROM AUTHOR]

Addressing issues such as susceptibility to background interference and variability in feature scales of fine-grained defects on metal surfaces, as well as the relatively poor versatility of the baseline model YOLOv8n, this study proposes a YOLO-ADS algorithm for metal surface defect detection. Firstly, a novel CSPNet with Average SPP-Fast Block (ASPPFCSPC) module is proposed to enhance the model's fusion and representation ability between local features and global background information. Secondly, the newly improved module C2f_SimDCNv2 is utilized to improve the ability of the model to extract multi-scale features. Finally, the Space-to-Depth (SPD) layer is introduced to prevent the loss of fine-grained information from small target features and reduce the redundancy between convolution operations. Experimental results demonstrate that the mean Average Precision (mAP) and Precision of the YOLO-ADS algorithm on the steel strip surface defect dataset NEU-DET reach 81.4% and 79.7%, which are severally increased by 3.5% and 6.1%, and the Frames Per Second (FPS) reaches 140.4. Meanwhile, the versatility and robustness of the model are verified on the industrial steel surface defect dataset GC10-DET, the industrial aluminum surface defect dataset APSPC and even the larger public benchmark dataset VOC2012, the mAP is respectively increased by 3.7%, 3.4% and 4.3%. Compared with the mainstream detection algorithms, YOLO-ADS algorithm is ahead of a certain advanced level in detection accuracy while maintaining a good real-time performance, which provides an efficient and feasible solution for the field of metal surface defect detection. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance (SPR) sensors are based on photon-excited surface charge density oscillations confined at metal-dielectric interfaces, which makes them highly sensitive to biological or chemical molecular bindings to functional metallic surfaces. Metal nanostructures further concentrate surface plasmons into a smaller area than the diffraction limit, thus strengthening photon-sample interactions. However, plasmonic sensors based on intensity detection provide limited resolution with long acquisition time owing to their high vulnerability to environmental and instrumental noises. Here, we demonstrate fast and precise detection of noble gas dynamics at single molecular resolution via frequency-comb-referenced plasmonic phase spectroscopy. The photon-sample interaction was enhanced by a factor of 3,852 than the physical sample thickness owing to plasmon resonance and thermophoresis-assisted optical confinement effects. By utilizing a sharp plasmonic phase slope and a high heterodyne information carrier, a small atomic-density modulation was clearly resolved at 5 Hz with a resolution of 0.06 Ar atoms per nano-hole (in 10–11 RIU) in Allan deviation at 0.2 s; a faster motion up to 200 Hz was clearly resolved. This fast and precise sensing technique can enable the in-depth analysis of fast fluid dynamics with the utmost resolution for a better understanding of biomedical, chemical, and physical events and interactions. [ABSTRACT FROM AUTHOR]

A set of Cu/ZnO/ZrO2 catalysts doped with Group‐IIIA elements (M=B, Al, Ga & In) were synthesized via a facile single‐step evaporation‐induced self‐assembly (EISA) method to tune up the catalyst basicity and modulate the structure to improve the methanol yield in CO2 hydrogenation reaction. To understand the catalyst‘s textural properties and catalytic activity, prepared catalysts were exposed to several in‐situ/ex‐situ characterization techniques like Physisorption & Chemisorption studies, XRD, XPS, TEM, and in‐situ DRIFT. The addition of group IIIA elements has a significant impact on the CO2 conversion and Methanol selectivity via tailoring the important textural properties such as metallic surface area of Cu, reducibility of catalysts, particle size, controlled oxygen vacancy, and basicity of catalyst surface. CZZ doped with Al appeared to be the best catalyst, in this study. The modified Cu‐ZnO interface via density functional theory (DFT) calculations also indicated that the CO2 adsorption energy is found to be highest for CZZAl, which is concomitant with CO2‐TPD analysis results. The lowest to highest CO2 adsorption energy order over the catalyst set follows CZZIn