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In the field of perovskite solar cells (PSCs), the research on defects in the buried interface has been relatively limited due to its non-exposure; however, this interface significantly impacts the performance enhancement of inverted PSCs. This study employs phenylethylammonium chloride (PEACl) molecules as a buffer layer to modify the buried interface of p-i-n structured PSCs, aiming to enhance the uniformity of self-assembled monolayers (SAMs) and facilitate the uniform nucleation and growth of perovskite films on the substrate. Furthermore, the introduction of the PEACl buffer layer effectively passivates defects at the bottom of the perovskite layer and notably enhances the crystal quality of the perovskite film by mitigating residual stress, thereby reducing nonradiative recombination loss. Following these optimizations, the MA-free PSCs treated with PEACl achieve a power conversion efficiency (PCE) of 24.11%, with significant improvements in storage, thermal stability, and operational stability. Particularly noteworthy is the device's performance in an unencapsulated state, whereas after 1,500 hours of continuous light operation stability testing, it retains 97% of its original efficiency. This study not only enriches the systematic understanding of the characteristics of the buried interface in PSCs but also contributes significantly to advancing the commercial production of perovskite photovoltaic technology. [ABSTRACT FROM AUTHOR]

This article proposes a new Ultra-Violet (UV)-C Light emitting Diode (LED) structure based on orderly aligned Quaternary Nitride alloy based specially-designed quantized quantum barrier. In this article, we theoretically investigate the performance such as internal quantum efficiency (IQE), efficiency droop etc. of proposed structure and also compare it with the reference UV-C LED structure. In this proposed structure, there is no sudden potential barrier as in case of reference structure because of the strain compensation provided by the quantized periodic Superlattice-AlxInyGa(1-x–y)N/ AlaGabN quantum barrier. Active region epilayer crystal orientation balanced by introducing 'In' molar content in alternate sub-layers of quantum barrier (QB). This allows for stronger carrier confinement in the active region, which enhances IQE to 72% from 32% (reference structure) and reduction in efficiency droop from 11% to 0.05% at current density of 200 A-cm−2. The variation in the density of states (DOS) for carrier allocation due to strain balance in the quantum barrier compared to the quantum wells (QW) is responsible for the significant increase in the electro-optical efficiency of the light emitting device. [ABSTRACT FROM AUTHOR]

Metallic heterostructural nanocrystals (HNCs) hold immense potential in electrocatalytic carbon dioxide reduction reaction (CO2RR) owing to their abundant active sites and high intrinsic activity. However, a significant challenge still remains in achieving controlled nucleation and growth sites for HNCs on supports and comprehending the influence of the structure–activity relationship on electrocatalytic CO2RR performance. This work presents a photochemical self-assembly technique without the necessity for reducing agents or facet-specific capping agents. By controlling lattice mismatch and manipulating transfer paths of photo-generated carriers, we can precisely direct the growth sites and nucleation of nanocrystals, enabling the self-assembly of supported core–shell and Janus nanostructures. Compared to Pd(T)@Au core–shell HNCs with the same loading, Pd cube–Au Janus HNCs exhibit significantly enhanced selectivity and stability toward carbon monoxide (CO) production in CO2RR at less negative potentials. The Pd cube–Au Janus HNC electrocatalyst achieved a Faradaic efficiency (FE) of 92.6 ± 3.5% for CO electroreduction, accompanied by a current density of 72.3 mA·cm−2 at −0.58 V. This work provides an effective strategy for designing advanced supported tandem electrocatalysts to boost the selectivity and durability test of CO2RR. [ABSTRACT FROM AUTHOR]

The present study elucidated the formation mechanism of γ′ rafting related to dislocation motion and clarified that γ′ rafting could be divided into the mismatch-driven stage I and diffusion-controlled stage II. This transition arose from the dual effects of dislocations: relaxing lattice mismatch and boosting elements diffusion. In detail, once the elastic misfit stress was nearly released by forming dense dislocation networks, the effective bulk diffusivity and the mobility of matrix dislocations would control the subsequent γ′ rafting. This study offered insights into the rafting of γ′ phase and proposed valuable suggestions to improve the microstructural stability of Ni-based single crystal superalloys.

This article is aimed at understanding of the complex design of metalorganic chemical vapour deposition ‐grown InGaN‐based red light‐emitting diode (LED) structure. The contribution of different elements of red LED structure to the stress distribution and threading dislocation density (TDD) evolution is theoretically investigated. For this purpose a self‐consistent modeling of the structure growth process is used, taking into account stress‐modulated indium incorporation, mismatch stress relaxation by threading dislocations and V‐pits, and nucleation of new threading dislocations. The simulation results, consisting of composition, stress, and TDD profiles, are then utilized for modeling of device operation, which allows to analyze contribution of different elements to the heterostructure operation. [ABSTRACT FROM AUTHOR]

BiFe0.91Zr0.09O3 (9BFZrO)/LaNiO3 (LNO)/MgO and 9BFZrO/LNO/Si multilayers were prepared by the sol–gel method using MgO and Si single crystals as substrates, and LNO films with a thickness of approximately 50 nm were deposited by magnetron sputtering to form bottom electrodes and transition layers. The effects of different substrates on the crystal structure, phase composition, oxygen vacancy content, ferroelectric properties, dielectric properties, leakage mechanism, and ageing properties of the 9BFZrO films were systematically analysed. X-ray diffraction showed that the prepared 9BFZrO thin films had a structure composed of both rhombic R3c and orthogonal Pnma phases, and the films prepared on the MgO substrate contained a significant amount of the R3c phase. SEM analysis showed that the thin film prepared on the MgO substrate had a relatively large grain size. X-ray photoelectron spectroscopy showed that the Fe2+ content and oxygen vacancy defect concentration of the MgO substrate samples were relatively low. The thin film prepared on the MgO substrate has a high residual polarization strength (2Pr = 60.28 μC/cm2) and a low leakage current density (4.71 × 10−6 A/cm2). After 90 days of room-temperature ageing, the residual polarization strength (2Pr) of the film on the MgO substrate decreased by 16.8%, with a lower ageing degree and better stability. [ABSTRACT FROM AUTHOR]

The influence of different calcium-containing alloys on inclusions in high-Al steel is investigated in the current study. The effects of SiCa, AlCa20, AlCa75 and FeSi alloys on the modification of solid inclusions in molten steel are compared, and the mechanism of inclusion evolution is revealed based on the non-uniform distribution of elements and the lattice mismatch between the inclusion particles. The results show that the Ca yield of FeSi alloy is 26%, which is significantly higher than that of other alloys (<5%). In addition, the calcium treatment by FeSi alloy causes less aspiration of molten steel, which is conducive to avoiding the increase of AlN in high-Al steel. After calcium treatment, the primary Al2O3 particles in steel are transformed into CaO-Al2O3-CaS and CaO-Al2O3-MgO complex inclusions, while AlN can only be precipitated in the form of a single particle, or precipitated from the transformed CaO · 2Al2O3 oxide. In general, FeSi alloy has the best effect on the modification of Al2O3 inclusions, which can maximize the transformation of solid particles into liquid inclusions in steel liquid without introducing too much impurities. [ABSTRACT FROM AUTHOR]

Mesocrystals are ordered nanoparticle superstructures, often with internal porosity, which receive much recent research interest in catalysis, energy storage, sensors, and biomedicine area. Understanding the mechanism of synthetic routes is essential for precise control of size and structure that affect the function of mesocrystals. The classical synthetic strategy of mesocrystal was formed via self-assembly of nanoparticles with a faceted inorganic core but a denser (or thicker) shell of organic molecules. However, the potential materials and synthetic handles still need to be explored to meet new applications. In this work, we develop a non-classical synthetic strategy for organic molecules, such as tetrakis (4-hydroxyphenyl) ethylene (TPE-4OH), tetrakis (4-bromophenyl) ethylene (TPE-4Br), and benzopinacole, to produce mesocrystals with composed of microrod arrays via co-solvent-induced crystal transformation. The aligned nanorods are grown epitaxially onto organic microplates, directed by small lattice mismatch between plates and rods. Thus, the present work offers general synthetic handle for establishing well-organized organic mesocrystals. [ABSTRACT FROM AUTHOR]

During the past decades, group-III nitrides have emerged as a new impetus for the development of semiconductor industry and attracted significant attentions in different fields. Among them, indium-bearing group-III nitrides, such as InGaN, InAlN and their quaternary alloy InAlGaN show an adjustable bandgap in wide range including visible spectrum and ultraviolet spectrum, and their excellent electronic properties have been predicted by theoretical calculations. Therefore, indium-bearing group-III nitrides demonstrate great potential as solid lighting and photoelectric detection materials. However, the growth of high-quality indium-bearing group-III nitrides is hindered by the phase segregation of indium component and the lattice mismatch between substrate and epitaxial layer. Tremendous efforts have been paid to solve these issues, and remarkable results have been achieved accordingly. This review mainly focuses on the impressive results of theoretical calculation on properties of indium-bearing group-III nitrides and the breakthroughs in their epitaxial growth, together with the development of electron devices and photoelectric devices based on indium-bearing group-III nitrides. Based on the recent progress, the prospective for the future evolution of indium-bearing group-III nitrides and devices is speculated ultimately. This review provides a guideline for better understanding of the development of indium-bearing group-III nitrides and devices. [ABSTRACT FROM AUTHOR]

In this paper, strong photoluminescence near-infrared (NIR)-emitting CdHgTe/ZnTe nanocrystals were synthesized using different thiol ligands 3-mercaptopropionic acid (MPA), L-Cysteine (L-Cys), and glutathione (GSH). This research utilizes a novel temperature-controlled microwave-assisted methodology via freezing-thawing (F-T) progress to synthesize superior CdHgTe/ZnTe core-shell nanocrystals. The study reveals that the photoluminescence quantum yields are markedly influenced by the synthesis parameters, including component types, concentration levels, and the choice of surface ligands. Different technologies including UV-vis, photoluminescence spectroscopy, transmission electron microscopy, powder X-ray diffraction and X-ray photoelectron spectroscopy were employed to characterize the as-prepared nanocrystals. The results showed that enhanced photoluminescence yield is primarily due to the low lattice mismatch (6%) between the CdHgTe core and the ZnTe shell materials, which significantly boosts the fluorescence stability and presents a low density of defects in the shell. Furthermore, the core-shell CdHgTe/ZnTe nanocrystals were successfully applied for fixed cells. The biocompatible ligands capped nanocrystals with bright fluorescence showed negligible photobleaching in fixed cells even after 40 min UV irradiation. This indicates that core-shell nanocrystals capped with L-Cysteine and Glutathione possess remarkably high resistance to photobleaching and oxidation. [ABSTRACT FROM AUTHOR]

The study investigates high-voltage gradual p0–i–n0 junctions in solid solutions of AlxGa1 – xAs1 – ySby with y up to 15%, which are capable of absorbing radiation with a wavelength of 1064 nm, grown on GaAs substrates by liquid-phase epitaxy through self-doping with background impurities. The composition of the liquid phase and the temperature range of growth are selected so that the aluminum-compound content x decreased steadily from the specified values of about 34% to a few percent at the surface of the epitaxial layer, while the antimony-compound content y increased. In this case, the band-gap width gradually decreased from the substrate to the surface of the lightly doped layer, reaching the desired value of ~1.16 eV. By measuring the capacity–voltage characteristics and deep level transient spectroscopy in them, configurationally bistable DX centers associated with donor impurities Si and Se/Te are identified. The investigated heterophase epitaxial layers reveal the absence of deep energy levels associated with dislocations. The effective lifetime of minority charge carriers in the base layers of the AlxGa1 – xAs1 – ySby/GaAs diode is determined using reverse recovery of the diode. Assuming that the minority-carrier lifetime is mainly determined by the capture of holes by the acceptor-like deep level DX – of Si in the n0 layer of the material, the hole capture cross section on the DX – level is estimated. The capture cross section is found to be 6 × 10–15 cm2. [ABSTRACT FROM AUTHOR]

Lattice mismatch significantly influences microscopic transport in semiconducting devices, affecting interfacial charge behavior and device efficacy. This atomic‐level disordering, often overlooked in previous research, is crucial for device efficiency and lifetime. Recent studies have highlighted emerging challenges related to lattice mismatch in perovskite solar cells, especially at heterojunctions, revealing issues like severe tensile stress, increased ion migration, and reduced carrier mobility. This review systematically discusses the effects of lattice mismatch on strain, material stability, and carrier dynamics. It also includes detailed characterizations of these phenomena and summarizes current strategies including epitaxial growth and buffer layer, as well as explores future solutions to mitigate mismatch‐induced issues. We also provide the challenges and prospects for lattice mismatch, aiming to enhance the efficiency and stability of perovskite solar cells, and contribute to renewable energy technology advancements. [ABSTRACT FROM AUTHOR]

Direct InN growth is demonstrated and characterized on a sapphire (Al2O3) substrate by plasma‐enhanced metal–organic chemical vapor deposition using high‐density nitrogen (N2) microstrip‐line microwave plasma. N2 plasma irradiation at 650 °C for 20 min forms AlN on Al2O3 substrate. No peak regarding metallic In droplets is detected from InN/Al2O3 regardless of N2 plasma irradiation. InN is found to be rotated 30° with their a‐axis oriented to become [101¯0]$[ {10\bar{1}0} ]$ InN // [112¯0]$[ {11\bar{2}0} ]$ Al2O3. The transition layers are confirmed at the InN/Al2O3 interface regardless of N2 plasma irradiation. The surface of InN consisted of large undulations with root mean square values >30 nm, suggesting that strain relaxation introduces misfit dislocations. [ABSTRACT FROM AUTHOR]

Strain engineering, as a cutting-edge method for modulating the electronic structure of catalysts, plays a crucial role in regulating the interaction between the catalytic surface and the adsorbed molecules. The electrocatalytic performance is influenced by the electronic structure, which can be achieved by introducing the external forces or stresses to adjust interatomic spacing between surface atoms. The challenges in strain engineering research lie in accurately understanding the mechanical impact of strain on performance. This paper first introduces the basic strategy for generating the strain, summarizes the different strain generation forms and their advantages and disadvantages. The progress in researching the characterization means for the lattice strains and their applications in the field of electrocatalysis is also emphasized. Finally, the challenges of strain engineering are introduced, and an outlook on the future research directions is provided. [ABSTRACT FROM AUTHOR]

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Alkaline water splitting currently represents one of the most promising routes for sustainable hydrogen production. However, the key challenge with this method lies in the development of low-cost catalysts showing high-performance for hydrogen evolution reaction (HER). Given the rapid advances in the structural design of HER catalysts, a potential procedure to boost their performance is introduced herein. A controllable interlayer stress is generated at the homojunction NiS/NiS interface of electrodeposited hybrid transition metal sulphide NiS/MoS 2 , by precisely regulating lattice mismatches of NiS nanostructures, achieve a precise control over its charge transfer resistance and the effective balance of electrochemical area. Accordingly, an optimal design, NM5030 (NiS(50 mA/cm2)-NiS(20 mA/cm2)/MoS 2 /CC), showing an excellent HER performance in alkaline electrolyte is produced. It can drive a high current density of 10 mA/cm2, 100 mA/cm2 and 400 mA/cm2 at a low overpotential of 18 mV, 93 mV and 161 mV, respectively. Under chronoamperometric test, no obvious reduction in current density is observed after 48 h, indicating its high stability. Overall, this work demonstrates the feasibility and effectiveness of the strategy of fabricating lattice mismatch to find an optimal layered structure based catalyst for efficient HER. • This work achieves precise regulation of the lattice mismatches of the catalyst. • This work quantifies and summarizes the relationship between charge transfer capacity and interlayer stress. • Our catalyst can drive a high current density of 10 mA/cm2 and 400 mA/cm2 at a low overpotential of 93 mV and 161 mV. [ABSTRACT FROM AUTHOR]

We report the study of photoelectrochemical performance of undoped, Zn-doped and Zn/P co-doped α-Fe 2 O 3 photoanodes prepared by one-step chemical vapor deposition. Since the radius of ions P5+ < Fe3+ < Zn2+, Zn/P co-doping can balance the ion radius difference after inserting heteroatom. Moreover, Zn/P co-doping in Fe 2 O 3 can significantly increase the donor concentration and promote carrier transfer in the bulk and on the surface of the Fe 2 O 3. The donor concentration of α-Fe 2 O 3 , Zn–Fe 2 O 3 and Zn/P–Fe 2 O 3 films are evaluated to be 1.59 × 1016, 5.25 × 1017 and 2.67 × 1018 cm−3, respectively. Zn/P–Fe 2 O 3 exhibits an impressive photocurrent density of 0.42 mA/cm2 at 1.23 V and a low onset potential of 0.36 V vs. RHE, while the applied bias photo-to-current efficiency of Zn/P–Fe 2 O 3 co-doped film is 0.125 % 0.73 V vs. RHE, which is 2.5 times of that of Zn–Fe 2 O 3. This study provides a new doping strategy to improve PEC water oxidation efficiency for Fe 2 O 3. • Zn/P co-doping in Fe 2 O 3 can balance the ion radius difference and alleviate the lattice mismatch. • Zn/P co-doping can significantly increase the donor concentration in Fe 2 O 3. • Zn/P co-doping in Fe 2 O 3 can narrow band gap and widen the wavelengths range of light absorption. [ABSTRACT FROM AUTHOR]

Fine sulfides can promote the refinement of microstructure and improve the strength and toughness of materials. The interface properties between sulfides and steel matrix are associated with this phenomenon. The first principles calculation combined with two-dimensional lattice mismatch and two-step nucleation theory is adopted to calculate the interface properties of TiS/bcc-Fe, TiS/fcc-Fe and TiS/MnS at the atomic level. The results show that TiS has a weak ability to promote the transition of austenite to intragranular ferrite (IGF) due to the low adhesion work value. And TiS needs to overcome energy barriers to induce the formation of IGF because the higher interface energy of TiS/bcc-Fe than TiS/fcc-Fe. The heterogeneous nucleation ability of TiS(001)/MnS(111) is stronger than that of TiS(001)/MnS(110), indicating that TiS is beneficial for improving the deformation performance of MnS without affecting the ability of MnS (110) surface to induce IGF nucleation for grain refinement. Based on the two-step nucleation theory, the structures and properties of TiS clusters are analyzed. The formation pathway of TiS/Fe interface can be described as: Tiatom + Satom + Featom → core (TiSn)–shell (fcc-Fe(111)) → core (TiS(001))–shell (fcc-Fe(110) + bcc-Fe(100)).

Aluminum scandium nitride (AlScN) has been receiving increasing interest for radio frequency microelectromechanical systems because of their higher achievable bandwidths owing to the larger piezoelectric response of AlScN compared to AlN. However, alloying scandium (Sc) with aluminum nitride (AlN) significantly lowers the thermal conductivity of AlScN due to phonon alloy scattering. Self-heating in AlScN devices potentially limits power handling, constrains the maximum transmission rate, and ultimately leads to thermal failure. We grew plasma-assisted molecular beam epitaxy (PAMBE) AlScN on AlN-Al2O3 and GaN-Al2O3 substrates, and compared the cross-plane thermal conductivity to current work on AlScN grown on Si substrates.

In this study, focused ion beam (FIB) and transmission electron microscopy (TEM) were used to investigate the morphology, composition, crystal structure, and phase interface growth orientation of the LaAlO3-Ti(C,N)-(Ti,Nb,Mo)C complex inclusion in GH4742 alloy. Based on the theory of lattice mismatch and the thermodynamic model of inclusion formation, the formation mechanism of composite inclusions was studied. Crystallographic analysis showed that Ti(C,N) grew on the LaAlO3 substrate, and its growth was restricted by the parallel orientation relationship with the LaAlO3 substrate. The (0006¯)LaAlO3//(1¯11)Ti(C,N) was the lowest lattice mismatch plane between the two phases, with a 1D lattice mismatch of 9.68% and a 2D lattice mismatch of 10.05%. The distance difference between two parallel planes was compensated by dislocations and lattice distortions. Ti(C,N) had lower lattice mismatch with TiC and LaAlO3, making it easier to grow on the LaAlO3 nucleus. Thermodynamic calculations indicate that oxides exist in solid form within the molten alloy. As the temperature decreases, TiN precipitates in the alloy melt, while TiC precipitates during the solidification process. These results provide an explanation for the formation process of the complex three-layer structure of the complex inclusions.

The elastic interaction of quantum disks (QDs) in a nanowire (NW), i.e., in a hybrid QD/NW structure with sharp heterointerfaces, is considered for the first time. Within the framework of the defect micromechanics approach, the energy of QD pair interaction is established and it is demonstrated that for QDs with a lattice misfit of the same sign, a zone of attraction to each other appears, depending on the ratio of the QD axial size to the NW radius. The discovered effect should be taken into account when choosing the modes of formation of hybrid QD/NW structures and in models explaining their properties. [ABSTRACT FROM AUTHOR]

Aluminum scandium nitride (AlScN) has been receiving increasing interest for radio frequency microelectromechanical systems because of their higher achievable bandwidths owing to the larger piezoelectric response of AlScN compared to AlN. However, alloying scandium (Sc) with aluminum nitride (AlN) significantly lowers the thermal conductivity of AlScN due to phonon alloy scattering. Self-heating in AlScN devices potentially limits power handling, constrains the maximum transmission rate, and ultimately leads to thermal failure. We grew plasma-assisted molecular beam epitaxy (PAMBE) AlScN on AlN-Al2O3 and GaN-Al2O3 substrates, and compared the cross-plane thermal conductivity to current work on AlScN grown on Si substrates. AlScN grown on AlN-Al2O3 and GaN-Al2O3 substrates achieve a better lattice match and a comparable thermal conductivity to AlScN grown on Si substrates, but with significantly thinner films. [ABSTRACT FROM AUTHOR]

ABSTRACTThe deformation of interatomic distances with respect to those of the perfect crystal generates atomic-level strain. In nanoalloys, strain can arise because of finite size, morphology, domain structure and lattice mismatch between their atomic compounds. Strain can strongly affect the functional properties of nanoalloys, as it alters their electronic energy levels. Moreover, atomic-level strain generates atomic-level stress, which in turn results in distortions induced by strain. When the stress accumulated in a nanoalloy exceeds a certain level, the particle can relax that stress by undergoing structural transitions such as shape and/or chemical ordering transitions. Atomic-level strain is then a powerful tool to control and manipulate the structural and functional properties of nanoalloys. This requires a combined theoretical and experimental approach both to deeply understand the physical origin of strain, and to characterize it with a sub-angstrom resolution. Here, we present a theoretical analysis of the main sources of strain in nanoalloys, we analyse how atomic-level strain can be experimentally measured with transmission electron microscopy, we discuss its effect on the functional properties of nanoalloys, finally we describe how atomic-level stress arises from atomic-level strain, and how stress can induce structural transformations at the nanoscale.

As nano-electronic technology makes electronic devices gradually microscopic in size and diversified in function, obtaining new materials with superior performance is the main goal at this stage. Interfaces formed by adjacent layers of material in electronic devices affect their performance, as does the strain caused by lattice mismatch, which can be simulated and analyzed by theoretical calculations. The common period of the cell changes when the van der Waals (vdW) material is twisted. Therefore, it is a significant challenge to determine the common supercell of two crystals constituting the interface. Here. we present a novel cell matching algorithm for twisted bilayer vdW materials with orthogonal unit cells, where the resulting common supercell remains orthogonal and only angular strains exist without linear strains, facilitating accuracy control. We apply this method to 2-Pmmn twisted bilayer borophene. It can automatically find the resource-allowed common supercell at multiple rotation angles or fix the rotation angle to find the proper accuracy. [ABSTRACT FROM AUTHOR]

Since the discovery of the low-temperature, long-range ferromagnetic order in monolayers Cr2Ge2Te6 and CrI3, many efforts have been made to achieve a room temperature (RT) ferromagnet. The outstanding deformation ability of two-dimensional (2D) materials provides an exciting way to mediate their intrinsic ferromagnetism (FM) with strain engineering. Here, we summarize the recent progress of strain engineering of intrinsic FM in 2D van der Waals materials. First, we introduce how to explain the strain-mediated intrinsic FM on Cr-based and Fe-based 2D van der Waals materials through ab initio Density functional theory (DFT), and how to calculate magnetic anisotropy energy (MAE) and Curie temperature (TC) from the interlayer exchange coupling J. Subsequently, we focus on numerous attempts to apply strain to 2D materials in experiments, including wrinkle-induced strain, flexible substrate bending or stretching, lattice mismatch, electrostatic force and field-cooling. Last, we emphasize that this field is still in early stages, and there are many challenges that need to be overcome. More importantly, strengthening the guideline of strain-mediated FM in 2D van der Waals materials will promote the development of spintronics and straintronics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Vertically aligned ZnO hexagonal columns are grown on Zn foil via a solution method. • The aligned ZnO columns can guide oriented Zn plating due to low lattice mismatch. • The Zn plating tends to occur along (0 0 2) facet associated with parallel plating. • The Zn metal corrosion and harmful side reactions can be effectively inhibited. • The cyclability of Zn//Zn cell and Zn//MnO 2 batteries can be significantly improved. Aqueous zinc-ion batteries (AZIBs), featuring low cost and high safety, have become a research hotspot in recent years. However, the low Zn stripping/plating reversibility, caused by dendritic growth, harmful side reactions, and Zn metal corrosion, severely influences the applicability of AZIBs. Zincophilic materials have shown great potential to form protective layers at the surface of Zn metal electrodes, whereas those protective layers are usually thick, lack fixed crystalline orientation, and require binders. Herein, a facile, scalable, and cost-effective solution method is used to grow vertically aligned ZnO hexagonal columns with (0 0 2) top surface and low thickness of 1.3 µm onto Zn foil. Such oriented protective layer can promote homogenous and nearly horizontal Zn plating not only on the top but also at the side of ZnO columns due to the low lattice mismatch between Zn (0 0 2) and ZnO (0 0 2) facets and between Zn (1 1 0) and ZnO (1 1 0) facets. Accordingly, the modified Zn electrode exhibits dendrite-free behavior with considerably suppressed corrosion issue, inert byproduct growth, and hydrogen evolution. Thanks to that, the Zn stripping/plating reversibility is significantly improved in Zn//Zn cell, Zn//Ti cell, and Zn//MnO 2 battery. This work provides a promising avenue for guiding metal plating process via oriented protective layer. [ABSTRACT FROM AUTHOR]

In this study, we investigated the optoelectronic behavior of In1−xGaxAs alloy epitaxy on a GaAs substrate by varying the chemical composition of gallium. We studied the impact of the elastic deformation generated by the lattice mismatch between the material and substrate on the bandgap energy and absorption coefficient. The hydrostatic pressure and temperature were considered. Our aim was to show that this constraint can also contribute to widening the bandgap range. The results were exploited to optimize the efficiency of solar cells based on copper indium gallium (di) selenide Cu (In, Ga) Se2 (CIGS) using an InGaAs absorbent layer, which must be strained to minimize the cost of the cell by reducing the Ga (x) content. [ABSTRACT FROM AUTHOR]

The mechanical properties and corrosion resistance of extruded Mg-8Li-3Al alloys with varying Gd contents are investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electrochemical tests. The results show that the size of α-Mg grains in extruded Mg-8Li-3Al alloys is obviously refined during the dynamic recrystallization process due to the addition of Gd. The ultimate tensile strength of extruded Mg-8Li-3Al-1.2Gd alloy attains to 278 MPa, which is approximately 35% higher than that of the matrix alloy (206 MPa). The improved mechanical properties of the Mg-8Li-3Al alloys containing Gd are mainly attributed to the formation of the Al2Gd phase, which can refine the α-Mg grain as a heterogeneous nucleation substrate and hinder the movement of the dislocations and grain boundaries and the rotation of the grains. The comprehensive electrochemical results show that the corrosion resistance of extruded Mg-8Li-3Al-xGd (x = 0.6, 1.2 and 1.8 wt.%) alloys is improved by the addition of Gd. In addition, the corrosion mechanism of extruded Mg-8Li-3Al alloys contained Gd is discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] Herein, we present a heterostructure electrolyte with considerable potential for application in low-temperature solid oxide fuel cells (LT-SOFCs). Heterostructure electrolytes are advantageous because the multiphase interfaces in their heterostructures are superior for ion conduction than for bulk conduction. Most previous studies on heterostructure electrolytes explained the influence of interfacial parameters on ion conduction in terms of the space charge zones and lattice mismatch, neglecting the characterization of the interface. In this study, a series of heterostructure electrolytes comprising La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ (LSCF) and BaTiO 3-δ (BTO) with different composition ratios was developed. Further, the lattice mismatch due to thermal stress in this system was evaluated by thermal expansion and electron energy loss spectroscopy (EELS) analyses. Results indicated that 7LSCF-3BTO produced the narrowest interface and the most surface oxygen vacancies, suggesting that the stress generated by thermal expansion increased the density of the interface. The cell with the optimal 7LSCF-3BTO composition delivered a peak power density of 910 mW cm−2 and an open circuit voltage of 1.07 V at 550 °C. The heterojunction effect was studied to elucidate the prevention of short circuiting in the LSCF-BTO cell, considering the Femi level and barrier energy height. This study provides novel ideas for the design of electrolytes for LT-SOFCs from the interface perspective. [ABSTRACT FROM AUTHOR]

Abstract Effective charge separation and transfer is deemed to be the contributing factor to achieve high photoelectrochemical (PEC) water splitting performance on photoelectrodes. Building a phase junction structure with controllable phase transition of WO3 can further improve the photocatalytic performance. In this work, we realized the transition from orthorhombic to monoclinic by regulating the annealing temperatures, and constructed an orthorhombic-monoclinic WO3 (o-WO3/m-WO3) phase junction. The formation of oxygen vacancies causes an imbalance of the charge distribution in the crystal structure, which changes the W-O bond length and bond angle, accelerating the phase transition. As expected, an optimum PEC activity was achieved over the o-WO3/m-WO3 phase junction in WO3-450 photoelectrode, yielding the maximum O2 evolution rate roughly 32 times higher than that of pure WO3-250 without any sacrificial agents under visible light irradiation. The enhancement of catalytic activity is attributed to the atomically smooth interface with a highly matched lattice and robust built-in electric field around the phase junction, which leads to a less-defective and abrupt interface and provides a smooth interfacial charge separation and transfer path, leading to improved charge separation and transfer efficiency and a great enhancement in photocatalytic activity. This work strikes out on new paths in the formation of an oxygen vacancy-induced phase transition and provides new ideas for the design of catalysts.

The immiscibility of crystallographic facets in multi‐metallic catalysts plays a key role in driving the green H2 production by water electrolysis. The lattice mismatch between tetragonal In and face‐centered cubic (fcc) Ni is 14.9 % but the mismatch with hexagonal close‐packed (hcp) Ni is 49.8 %. Hence, in a series of Ni−In heterogeneous alloys, In is selectively incorporated in the fcc Ni. The 18–20 nm Ni particles have 36 wt % fcc phase, which increases to 86 % after In incorporation. The charge transfer from In to Ni, stabilizes the Ni0 state and In develops a fractional positive charge that favors *OH adsorption. With only 5 at% In, 153 mL h−1 H2 is evolved at −385 mV with mass activity of 57.5 A g−1 at—400 mV, 200 h stability at −0.18 V versus reversible hydrogen electrode (RHE), and Pt‐like activity at high current densities, due to the spontaneous water dissociation, lower activation energy barrier, optimal adsorption energy of OH− ions and the prevention of catalyst poisoning. [ABSTRACT FROM AUTHOR]

Ultra‐thin rare earth iron garnet (RIG) films with a narrow ferromagnetic resonance (FMR) line width and a low damping factor have attracted a great deal of attention for microwave and spintronic applications. In this work, 200 nm Y3(GaAlFe)5O12 garnet (GaAl‐YIG) films were prepared on gadolinium gallium garnet (GGG) substrates by liquid‐phase epitaxy (LPE) with low saturation magnetization. The microstructural properties, chemical composition, and magnetostatic and dynamic magnetization characteristics of the films are discussed in detail. According to the structural analysis, these films exhibit a low surface roughness of less than 0.5 nm. The GaAl‐YIG films show an obvious temperature dependence of lattice parameter and strain state, and the film's parameter is perfectly matched with that of the GGG substrate at 810°C. There is a clear variation in the Pb level, which brings about a gradual enhancement of the coercivity and a diminution of the squareness ratio of magnetic hysteresis loops as the growth temperature is reduced. Slight changes in surface roughness, strain condition and content of Pb induce the FMR line width and damping factor to vary on a small scale. The line width is less than 10.17 Oe at 12 GHz and the damping factor is of the order of 10−4. All these properties demonstrate that these ultra‐thin GaAl‐YIG films are of benefit for the development of devices operated at lower frequencies and in lower fields. [ABSTRACT FROM AUTHOR]

Plasmonic metal-semiconductor hetero-structures exhibit synergetic coupling of plasmon and exciton, and therefore are promising in enhancing solar energy conversion. A well-ordered metal-semiconductor interface is of critical importance to prevent photocarriers recombination and amplify this coupling effect. Here, by a topotactic cation exchange strategy, we realized the synthesis of a centimeter-scale Au-CdS hetero-film with an atomic-organized interface. The obtained CdS films possess a hexagonal lattice, in contrast to the cubic structure that epitaxial grown on the polycrystalline Au substrate. First-principal calculations reveal CdS of hexagonal structure is energetically preferred in nature, indicating the growth of CdS film by topotactic cation exchange strategy is independent of the polycrystalline Au substrate. Under AM 1.5 G illumination, their photoelectrochemical hydrogen evolution activity is nearly 3.0 times higher than epitaxial grown hetero-film. Our work opens up the opportunity for synthesizing metal-semiconductor hetero-films with atomic-organized interfaces, paving the way for solar-to-fuel applications. [Display omitted] • Novel strategy to metal-semiconductor hetero-interface by topotactic cation exchange. • Cubic phase metal-hexagonal semiconductor hetero-films with atomic-organized interfaces are realized. • New photoexcited dynamics were achieved with enhanced charge transfer efficiency. • 3.0-fold enhancement in the performance of photoelectrochemical hydrogen evolution. [ABSTRACT FROM AUTHOR]

In this study, modeling of optimized lattice mismatch by carbon-dioxide annealing on (In, Ga) co-doped ZnO multi-deposition thin films was investigated with crystallography and optical analysis. (In, Ga) co-doped ZnO multi-deposition thin films with various types of bottom layers were fabricated on sapphire substrates by solution synthesis, the spin coating process, and carbon-dioxide laser irradiation with post annealing. (In, Ga) co-doped ZnO multi-deposition thin films with Ga-doped ZnO as the bottom layer showed the lowest mismatch ratio between the substrate and the bottom layer of the film. The carbon-dioxide laser annealing process can improve electrical properties by reducing lattice mismatch. After applying the carbon-dioxide laser annealing process to the (In, Ga) co-doped ZnO multi-deposition thin films with Ga-doped ZnO as the bottom layer, an optimized sheet resistance of 34.5 kΩ/sq and a high transparency rate of nearly 90% in the visible light wavelength region were obtained. [ABSTRACT FROM AUTHOR]

Low-dimensional materials have excellent properties which are closely related to their dimensionality. However, the growth mechanism underlying tunable dimensionality from 2D triangles to ID ribbons of such materials is still unrevealed. Here, we establish a general kinetic Monte Carlo model for transition metal dichalcogenides (TMDs) growth to address such an issue. Our model is able to reproduce several key ñndings in experiments, and reveals that the dimensionality is determined by the lattice mismatch and the interaction strength between TMDs and the substrate. We predict that the dimensionality can be well tuned by the interaction strength and the geometry of the substrate. Our work deepens the understanding of tunable dimensionality of low-dimensional materials and may inspire new concepts for the design of such materials with expected dimensionality. [ABSTRACT FROM AUTHOR]

We argue that alternating-layer structures of lattice mismatched or misaligned (twisted) atomically-thin layers should be expected to be more efficient absorbers of the broad-spectrum of solar radiation than the bulk material of each individual layer. In such mismatched layer-structures the conduction and valence bands of the bulk material, split into multiple minibands separated by minigaps confined to a small-size emerging Brillouin zone due to band-folding. We extended the Shockley-Queisser approach to calculate the photovoltaic efficiency for a band split into minibands of bandwidth Δ E and mini-gaps δ G to model the case when such structures are used as solar cells. We find a significant efficiency enhancement due to impact ionization processes, especially in the limit of small but non-zero δ G , and a dramatic increase when fully concentrated Sun-light is used., (Creative Commons Attribution license.)

The 90-year-old Hume-Rothery rule was adapted to design an outstanding bifunctional tetra-metallic alloy electrocatalyst for water electrolysis. Following the radius mismatch principles, Fe (131 pm) and Ni (124 pm) are selectively incorporated at the Pd (139 pm) site of Mo 0.30 Pd 0.70 nanosheets. Analogously, Cu (132 pm) alloys with only Pd, while Ag (145 pm) alloys with both Pd and Mo (154 pm). The face-centered cubic Mo 0.30 Pd 0.35 Ni 0.23 Fe 0.12 nanosheets with 10-12 atomic layers, featuring in-plane compressive strain along the {111} basal plane, show 1/3 (422) reflection from local hexagonal symmetry. The more electronegative Pd attracts electron density from Ni/Fe in Mo 0.30 Pd 0.35 Ni 0.23 Fe 0.12 , synergistically boosting the mass activities for hydrogen and oxygen evolution reactions to 89 ± 5 and 38.6 ± 3.1 A g -1 at ±400 mV versus RHE, respectively. Full water electrolysis continues for ≥550 h, requiring cell voltages of 1.51 and 1.63 V at 10 and 100 mA cm -2 , delivering 45 mL h -1 green H 2 .

Metal batteries have captured significant attention for high-energy applications, owing to their superior theoretical energy densities. However, their practical viability is impeded by severe dendrite formation and poor cycling stability. To alleviate these issues, a 3D-structured bimetallic-Mo 2 Ti 2 C 3 T x based fiber electrode was fabricated in this study and analyzed experimentally and computationally. The bimetallic Mo-Ti composition of MXenes synergistically achieved low binding and formation energies with lithium. In particular, the minimal lattice mismatch between the deposited Li metal and the Mo 2 Ti 2 C 3 T x MXene anode substrate led to improved Li formation energy with respect to the MXene surface. Moreover, the synergy of the bimetallic Mo-Ti composition of the Mo 2 Ti 2 C 3 T x MXene fiber substrate helped to amplify ion diffusion and reversible charge transfer. Consequently, the bimetallic MXene electrode exhibited an impressive Coulombic efficiency (99.08%) even at a high current density (5 mA cm -2 ) and a fixed cutoff capacity of 1 mA h cm -2 with prolonged cycle life (650 cycles). This report highlights a promising advancement in addressing the critical challenges facing metal battery operation, thereby offering an approach to improving performance for high-energy applications.