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Metal‐semiconductor interfaces are crucial components of optoelectronic and electrical devices, the performance of which hinges on intricate dynamics involving charge transport and mechanical interaction at the interface. Nevertheless, structural changes upon photoexcitation and subsequent carrier transportation at the interface, which crucially impact hot carrier stability and lifetime, remain elusive. To address this long‐standing problem, they investigated the electron dynamics and resulting structural changes at the Au/TiO2 interface using ultrafast electron diffraction (UED). The analysis of the UED data reveals that interlayer electron transfer from metal to semiconductor generates a strong coupling between the two layers, offering a new way for ultrafast heat transfer through the interface and leading to a coherent structural vibration that plays a critical role in propagating mechanical stress. These findings provide insights into the relationship between electron transfer and interfacial mechanical and thermal properties. [ABSTRACT FROM AUTHOR]

In order to enhance the hardness and wear resistance of 316L alloy, a strengthening phase was incorporated and laser-directed energy deposition was utilized to create a composite deposition layer consisting of coarse WC/316L, fine WC/316L, and coarse/fine WC/316L. Microstructural observations, phase composition analysis, Vickers hardness testing, interfacial coupling analysis, x-ray diffraction (XRD), and evaluation of friction-wear performance were systematically performed on the deposited samples. These investigations were undertaken to elucidate the impact of incorporating WC particles on both microstructural features and wear characteristics. Results showed that the average grain size of the composite deposition sample with coarse WC/316L decreased by 24% compared to 316L, with a 15.9% increase in hardness and a 97.6% decrease in wear rate. Similarly, the fine WC/316L composite deposition sample saw a 23% reduction in grain size, a 6.4% hardness increase, and a 62.4% decrease in wear rate compared to 316L. The hardness increased by 6.4%. The wear rate decreased by 62.4%. The coarse/fine WC/316L composite deposition samples exhibited a 34% decrease in average grain size, a 35.9% hardness increase, and a 99.1% decrease in wear rate compared to 316L. The addition of WC significantly enhanced the properties of 316L alloy, with coarse/fine WC showing the most significant improvements in microhardness and wear resistance. [ABSTRACT FROM AUTHOR]

Hollow semiconductor nanostructures with direct Z-scheme heterojunction have significant advantages for photocatalytic reactions, and optimizing the interfacial charge transmission of Z-scheme heterojunction is the hinge to achieve excellent solar conversion efficiency. In this work, tubular Ni1-xCoxS2-CdS heterostructures with reinforced Z-scheme charge transmission were constructed through an In-metal-organic framework (MOF) templated strategy. The Z-scheme charge transfer mechanism was sufficiently confirmed by combining density functional theory (DFT) calculation, X-ray photoelectron spectroscopy (XPS), surface photovoltage spectroscopy (SPV), and radical testing results. Crucially, the use of sodium citrate complexant contributes to the formation of intimate heterointerface, and the Fermi level gap between CdS and NiS2 is enlarged through Co doping into NiS2, which enhances the built-in electric field and photo-carriers transmission driving force for Ni1-xCoxS2-CdS heterojunction, resulting in an evidently promoted activity toward H2 evolution reaction (HER). Under visible-light (λ > 400 nm) irradiation, the Ni1-xCoxS2-CdS composite with 10 mol% Co doping and 80 wt.% CdS (NC0.10S-80% CdS) achieved an outstanding HER rate up to 35.94 mmol·g-1·h-1 (corresponding to the apparent quantum efficiency of 34.7% at 420 nm), approximately 76.4 times that of 3 wt.% Pt-loaded CdS and it is much superior to that of most CdS-based photocatalysts ever reported. Moreover, the good photocatalytic durability of Ni1-xCoxS2-CdS heterostructures was validated by cycling and long-term HER tests. This work could inspire the development of high-performance Z-scheme heterojunction via optimizing the morphology and interfacial charge transmission. [ABSTRACT FROM AUTHOR]

In research out of the sustainable electrochemical energy storage material, NiCo-LDH/MnO 2 composite has been prepared via simple hydrothermal method. The experimental characterizations of XRD, SEM/TEM and XPS have been utilized to explore the structure and morphology of prepared composite. The needle-like MnO 2 was found adhered to NiCo-LDH sheet. The composite's electrochemical properties were evaluated through cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. It has been realized that the MnO 2 dosage not only changes the composite's microstructure but also affects its electrochemical properties. The best specific capacitance (2602 F g−1 at a current density of 1 A g−1) was achieved for the composite sample with 38% MnO 2 (mass), which is almost two times high from the same composite in previous reports. With the sample, the assembled asymmetric supercapacitor exhibits a remarkable energy density of 19.56 Wh.Kg−1 at 800.29 W Kg−1. It could be attributed to the synergetic effects of two components as well as their good interfacial coupling. The good electrochemical activity makes our synthesized composite feasible to be applied as electrode material and provides valuable insights for the development of smart capacitors utilizing NiCo-LDH. [ABSTRACT FROM AUTHOR]

Abstract Metal‐semiconductor interfaces are crucial components of optoelectronic and electrical devices, the performance of which hinges on intricate dynamics involving charge transport and mechanical interaction at the interface. Nevertheless, structural changes upon photoexcitation and subsequent carrier transportation at the interface, which crucially impact hot carrier stability and lifetime, remain elusive. To address this long‐standing problem, they investigated the electron dynamics and resulting structural changes at the Au/TiO2 interface using ultrafast electron diffraction (UED). The analysis of the UED data reveals that interlayer electron transfer from metal to semiconductor generates a strong coupling between the two layers, offering a new way for ultrafast heat transfer through the interface and leading to a coherent structural vibration that plays a critical role in propagating mechanical stress. These findings provide insights into the relationship between electron transfer and interfacial mechanical and thermal properties.

To maximize the active sites and accelerate the electron transfer are of significant importance for developing efficient MoS 2 -based catalysts towards hydrogen evolution reaction (HER). Herein, we report a facile one-step construction of three-dimensional assembly in which Co doped MoS 2 nanoflowers are attached on partially sulfided nickel foam (Co–MoS 2 /Ni 3 S 2 /Ni). The three-dimensional structure enables maximum exposure of the active sites. Besides, interfacial interaction between MoS 2 and Ni 3 S 2 accelerates the electron transfer kinetics and increases the electrochemically active surface area. Additionally, electronic synergy effect of Co to MoS 2 promotes the formation of 1T-MoS 2 phase. Consequently, the optimized Co–MoS 2 /Ni 3 S 2 /Ni catalyst shows a superior HER performance with low overpotentials of 43 mV and 201 mV to achieve the current densities of 10 mA/cm2 and 100 mA/cm2, as well as an excellent stability of 11 h. Besides, Co–MoS 2 /Ni 3 S 2 /Ni has a small Tafel slope of 53 mV dec−1 which indicates a combined Volmer-Heyrovsky mechanism during the HER process. This work provides a novel insight for designing excellent MoS 2 -based HER catalysts through electronic modulation and interfacial engineering. [Display omitted] • One-step construction of three-dimensional Co–MoS 2 /Ni 3 S 2 /Ni assembly was realized. • Interfacial effect and electronic modulation are conducive to improving the HER activity of MoS 2. • Low overpotential of 43 mV to reach current density at 10 mA cm−2 was achieved. • The Co–MoS 2 /Ni 3 S 2 /Ni shows excellent stability in alkaline media. [ABSTRACT FROM AUTHOR]

• The symmetry of MoS 2 could be broken showing typical optical anisotropic property. • The MoS 2 /BiOCl exhibits polarization-sensitive photodetection with dichroic ratio of 1.10. • The type II band alignment can significantly reduce the dark noise current and enhance the value of specific detectivity. While MoS 2 as a two-dimensional semiconductor exhibits light-intensity broadband photodetection and can be synthesized using a 12-inch wafer-scale growth technique, its isotropic optical properties limit its application in multi-dimensional photodetection including polarization, intensity and wavelength photodetection. In this study, BiOCl flakes with optical anisotropy are employed to fabricate MoS 2 /BiOCl van der Waals (vdW) heterojunction. Characterizing with Raman spectroscopy, second harmonic generation (SHG), and kelvin probe force microscope (KPFM), strong interfacial coupling between MoS 2 and BiOCl is observed, which is potent enough to break the symmetry of MoS 2 , resulting in distinctive anisotropic optical properties. The electrical and photoelectrical properties of MoS 2 /BiOCl vdW heterojunction-based phototransistors are studied. The highest responsivity and specific detectivity under 460 nm illumination reaches 188 A/W and 5 × 1013 Jones, respectively. Moreover, the photocurrent of MoS 2 /BiOCl phototransistor exhibits typical polarization-sensitive behavior at 633 nm with a polarization dichroic ratio of 1.10, which is caused by the uniaxial strain from the interfacial coupling. This study paves the way for the development of a room-temperature multi-dimensional photodetector based on symmetry-broken MoS 2. [ABSTRACT FROM AUTHOR]

• High pressure drives the rapid implantation of polyaniline in host [VO n ] lattices. • Bipolar protonation provides abundant active sites for ion/electron mobility. • Interfacial coupling bonds effectively relieve the intercalation stress of V 2 O 5. • Charge storage process with multiple ions was elucidated by in situ FTIR/Raman. • AZIBs exhibits ultrahigh-rate and ultralong-life zinc ions storage performance. Durable cathode materials with high specific capacity are essential for aqueous zinc ion batteries (AZIBs). However, vanadium-based materials endure irreversible structural collapse, sluggish diffusion kinetics, and low working voltage. In this study, we propose a unique pressure-driven molecule implantation (PMI) strategy to fabricate a laminar organic–inorganic hybrid cathode (PMI-VO) for AZIBs by coupling polyaniline (PANI) with vanadium oxide. The bipolar protonation of implanted electroactive PANI provides abundant active sites for ion/electron transfer and Zn2+/H+ storage in PMI-VO. Importantly, the formed C-V-O interfacial coupling bonds in the cycling process effectively relieve the intercalation stress and strengthen the redox kinetics and structural integrity of V 2 O 5. In situ infrared spectroscopy and theoretical calculations reveal the PMI-induced multiple ions storage mechanisms in the PMI-VO cathode. Accordingly, PMI-VO cathode performs a superior specific capacity of 522 mAh∙g−1 at 0.2 A∙g−1, a high operating voltage of 0.86 V, a high energy density (387.4 Wh∙kg−1), and splendid long-life stability (over 15,000 cycles at 20 A∙g−1 with 191 mAh∙g−1). Therefore, this pressure-driven molecule implantation strategy provides a pioneering method to fabricate superior cathode materials of advanced AZIBs. [ABSTRACT FROM AUTHOR]

Probing and manipulating the intriguing nonlinear optical responses in van der Waals (vdW) ferroelectrics offer opportunities for their applications in nanophotonics. Here, we report the observation of giant and tunable second-harmonic generation (SHG) in ferroelectric CuInP 2 S 6 (CIPS) and CIPS/MoS 2 heterostructures. The results show that CIPS, ranging from multilayer to bulk-like samples, all exhibit strong SHG with giant anisotropy. The SHG anisotropy is attributed to the local strain along the a -axis that naturally exists in CIPS, as evidenced by piezoresponse force microscopy measurement. We further realized the strong modulation of SHG in CIPS by interfacing with monolayer MoS 2 . A combination of polarization, temperature, and thickness-dependent SHG and photoluminescence analyses shows that the nonlinear optical signal control in CIPS/MoS 2 heterostructures is unrelated to the polar symmetry of CIPS and MoS 2 but is driven by light absorption-mediated interfacial coupling. Our study provides a material platform based on vdW ferroelectric heterostructures for achieving dynamic control of nonlinear optical responses, which shows great potential applications in modern nanophotonics.

Metal-semiconductor interfaces are crucial components of optoelectronic and electrical devices, the performance of which hinges on intricate dynamics involving charge transport and mechanical interaction at the interface. Nevertheless, structural changes upon photoexcitation and subsequent carrier transportation at the interface, which crucially impact hot carrier stability and lifetime, remain elusive. To address this long-standing problem, they investigated the electron dynamics and resulting structural changes at the Au/TiO 2 interface using ultrafast electron diffraction (UED). The analysis of the UED data reveals that interlayer electron transfer from metal to semiconductor generates a strong coupling between the two layers, offering a new way for ultrafast heat transfer through the interface and leading to a coherent structural vibration that plays a critical role in propagating mechanical stress. These findings provide insights into the relationship between electron transfer and interfacial mechanical and thermal properties., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Due to promising functionalities that may dramatically enhance spintronics performance, antiferromagnets are the subject of intensive research for developing the next-generation active elements to replace ferromagnets. In particular, the recent experimental demonstration of tunneling magnetoresistance and electrical switching using chiral antiferromagnets has sparked expectations for the practical integration of antiferromagnetic materials into device architectures. To further develop the technology to manipulate the magnetic anisotropies in all-antiferromagnetic devices, it is essential to realize exchange bias through the interface between antiferromagnetic multilayers. Here, the first observation on the omnidirectional exchange bias at an all-antiferromagnetic polycrystalline heterointerface is reported. This experiment demonstrates that the interfacial energy causing the exchange bias between the chiral-antiferromagnet Mn 3 Sn/collinear-antiferromagnet MnN layers is comparable to those found at the conventional ferromagnet/antiferromagnet interface at room temperature. In sharp contrast with previous reports using ferromagnets, the magnetic field control of the unidirectional anisotropy is found to be omnidirectional due to the absence of the shape anisotropy in the antiferromagnetic multilayer. The realization of the omnidirectional exchange bias at the interface between polycrystalline antiferromagnets on amorphous templates, highly compatible with existing Si-based devices, paves the way for developing ultra-low power and ultra-high speed memory devices based on antiferromagnets., (© 2024 The Authors. Advanced Materials published by Wiley‐VCH GmbH.)

• Antiferromagnetics-based coercivity control in hematite/permalloy heterostructures. • Magnetic and structural studies of epitaxial hematite thin films across the Morin transition. • Thickness dependence of the Interfacial coupling between hematite and permalloy across Morin transition. Interfacial effects between antiferromagnetic (AFM) and ferromagnetic (FM) materials have long been a center of magnetism studies. Aside from the exchange bias occurring at the AFM/FM interface, controlling the coercivity is another significant topic in magnetic recordings. The coercivity of FM materials is often determined through varying grain size, alloy composition, density of defects, etc., which is set during material growth and offers limited room for modification after growth. Hematite (α - F e 2 O 3) is an AFM material that undergoes a temperature-controlled spin-flip transition, the so-called Morin transition. This transition gives an extra degree of freedom making hematite an intriguing component to study the exchange coupling when interfaced with an FM material. In this work, changes in the magnetic properties of soft magnetic permalloy (N i 81 F e 19 , or Py) thin films grown on hematite were studied across the Morin transition. Surprisingly, these samples showed a remarkable change in coercivity during the Morin transition. We attribute this effect to the magnetic domain mixture of hematite during the Morin transition. Our findings present a novel method of controlling the coercivity of plain ferromagnetic thin films. [ABSTRACT FROM AUTHOR]

Sewage containing heavy metal ions (HMIs) has caused serious damage to ecological environment and human health when discharged without treatment. In this work, a practical filter has been made with cellulose/zinc oxide/magnesium hydroxide (CelZnMg) ternary composite prepared via a simple hydrothermal method. The characterizations show that granular ZnO and lamellar Mg(OH) 2 evenly distribute on cellulose. The electrostatic attraction drives the coupling of cellulose and ZnO/Mg(OH) 2 , and the formed CelZnMg is significantly stabilized by interfacial hydrogen bonds and dative bonds. On the other hand, the cellulose substrate also immobilizes the recovered HMIs and completely and easily separates them from wastewater. The ternary composite has outstanding bifunctional performance. Its Mg(OH) 2 component offers high HMIs-removing capability; for instance, q max of Cd2+ and Cu2+ in 400 mL 500 mg·L–1 solution reaches 693.2 and 764.6 mg·g–1 respectively. The ZnO moiety endows the antibacterial property, which inhibits the growth of Staphylococcus aureus and Escherichia coli. The inhibition effect indicates that cellulose in the composite is stable during application. Due to its multiple merits, the CelZnMg filter would be a perspective candidate for the use as water treatment agent. [Display omitted] • Biobased fibrous cellulose composite is prepared by a simple hydrothermal method. • Granular ZnO and lamellar Mg(OH) 2 evenly and chemically anchor on cellulose. • Chemical and structural stability is enhanced by incorporating ZnO. • Mg(OH) 2 plays the key role in HMIs, which also slightly raises antibacterial effect. • Cellulose immobilizes recovered HMIs and completely avoids the secondary pollution. [ABSTRACT FROM AUTHOR]

Benefiting from abundant sodium resources, sodium-ion batteries (SIBs) have attracted abundant interest in the past decade, which hold great practical prospects for future large-scale energy storage applications. However, sluggish reaction kinetics are the main obstacle to the development of high-performance SIBs. Herein, nitrogen-doped carbon-coated MoSe 2 (MoSe 2 @NC) nanosheets are developed by a facile hydrothermal with subsequent calcination strategy. The expanded crystalline planes of MoSe 2 facilitate the insertion/extraction kinetics of Na+. The coated nitrogen-doped carbon layers effectively enhance the electric conductivity and restrict the agglomeration of MoSe 2. The Mo–C bonding formed by interfacial coupling between the MoSe 2 and nitrogen-doped carbons facilitates the charge transfer in the MoSe 2 @NC. As a result, the MoSe 2 @NC anode exhibits a reversible discharge capacity of 427.6 mAh g−1 at 0.1 A g−1 with a high cyclic stability of 337.9 mAh g−1 after 200 cycles at 0.5 A g−1. The N-doped carbon layers effectively restrict the agglomeration of MoSe 2 , and the expanded crystalline planes with strong interfacial Mo–C bonding facilitate the insertion/extraction reaction kinetics. [Display omitted] • The expanded crystalline planes of MoSe 2 @NC facilitate the insertion/extraction reaction kinetics. • The coated N-doped carbon layers effectively enhance the electric conductivity and restrict the agglomeration of MoSe 2. • The interfacial coupling of Mo–C bonding between the MoSe 2 and N-doped carbons facilitates the charge transfer. [ABSTRACT FROM AUTHOR]

The generally nonpolar SrTiO 3 has attracted more attention recently because of its possibly induced novel polar states and related paraelectric-ferroelectric phase transitions. By using controlled pulsed laser deposition, high-quality, ultrathin, and strained SrTiO 3 layers were obtained. Here, transmission electron microscopy and theoretical simulations have unveiled highly polar states in SrTiO 3 films even down to one unit cell at room temperature, which were stabilized in the PbTiO 3 /SrTiO 3 /PbTiO 3 sandwich structures by in-plane tensile strain and interfacial coupling, as evidenced by large tetragonality (∼1.05), notable polar ion displacement (0.019 nm), and thus ultrahigh spontaneous polarization (up to ∼50 μC/cm 2 ). These values are nearly comparable to those of the strong ferroelectrics as the PbZr x Ti 1- x O 3 family. Our findings provide an effective and practical approach for integrating large strain states into oxide films and inducing polarization in nonpolar materials, which may broaden the functionality of nonpolar oxides and pave the way for the discovery of new electronic materials.

[Display omitted] • Amorphous-crystalline interface coupling deign is proposed for active OER catalyst. • It is demonstrated by crystalline Fe 2 O 3 supported ultrathin amorphous NiFe(OH) x. • Reduced surface charge accumulation and promoted high valence Ni state is confirmed. • Enhanced OER activity is achieved in AEM electrolyzer at high current density. Amorphous NiFe-based oxyhydroxides can provide abundant active sites for oxygen evolution reaction (OER) in alkaline water splitting, but their disordered atomic arrangement leads to severe charge accumulation and electrochemical polarization at high current density. To address this issue, a crystalline Fe 2 O 3 supported ultrathin amorphous NiFe oxy-hydroxide amorphous-crystalline interface coupling design is proposed. In this design, the interfacial Fe3+ in Fe 2 O 3 as a strong Lewis acid is conducive for trapping the electrons in amorphous NiFe(OH) x , reducing the surface charge accumulation, electrochemical polarization, and improves its OER performance. Meanwhile, in-situ Raman, in-situ IR and XPS analysis reveal that, the electrons transfer is accompanied with Ni2+ oxidation into the highly OER active Ni3+ species. Benefited from this design, the OER overpotentials of the resulting NiFe(OH) x /Fe 2 O 3 NAs catalyst are measured to be 111 and 233 mV at 10 and 100 mA cm−2, respectively, superior than many reported OER electrocatalysts. The anion exchange membrane water electrolyzer using NiFe(OH) x /Fe 2 O 3 NAs delivers a current density of 600 mA cm−2 at a small cell voltage of 1.75 V, and exhibits excellent stability performance in high-current–density condition. This work provides a promising alternative strategy for the development of high-performance amorphous OER catalysts. [ABSTRACT FROM AUTHOR]