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Near‐infrared (NIR) phosphor‐converted light–emitting diodes (pc‐LEDs) are increasingly used in night vision, surveillance, and biomedicine. A major challenge is to identify a phosphor that efficiently converts blue light into wideband NIR emission. In this paper, a rare‐earth divalent europium (Eu2+)‐activated halogen oxide (Sr3GeO4Cl2) phosphor is unlocked via a high‐temperature solid‐state reaction. The Sr3GeO4Cl2:Eu2+ phosphor emits a wide spectrum (500–950 nm) with a peak at 700 nm when excited by 450 nm blue light. Extended X‐ray absorption fine structure (EXAFS) analysis reveals that the NIR emission primarily originates from Eu2+ ions, and the Eu─O bond length closely resembles the Sr─O bond length. Lattice engineering, specifically Ge/Si cation substitution, increased Eu2+ incorporation into the crystal lattice, boosting luminescence intensity by 75%–122% and quantum efficiency from 15% to 26%. This is related to the combined effect of reduced non‐radiative energy transfer and changes in the local lattice structure of Eu2+. A NIR pc‐LED device using the optimized phosphor showed a photoelectric efficiency of 16.5% and an optical output of 25.07 mW at 100 mA. This study not only explores new Eu2+‐activated NIR phosphors but also highlights the importance of crystal engineering to enhance luminescence properties, guiding future research for efficient NIR pc‐LED development. [ABSTRACT FROM AUTHOR]

Prevailing Li‐rich layered oxide cathodes (LLOs) possessing with polycrystalline morphology suffer from unsatisfactory cyclic stability due to serious structural failures including irreversible oxygen release, phase transformation, and microcrack, further limiting its commercial application for high‐energy‐density lithium‐ion batteries. Herein, single‐crystallization combining with a simple boric acid treatment strategy is applied to robust the stability of lattice structure for achieving the reversible oxygen anionic redox of LLOs. The obtained single‐crystal LLOs display less grain boundaries and excellent mechanical stability, contributing to suppress the accumulation of lattice strain and microcracks. Additionally, the induced surface Li2B4O7 with spinel phase coating and bulk gradient B doping after boric acid treatment significantly inhibit the irreversible oxygen release and enhance the stability of lattice structure. Besides, lattice structure regulation also boosts the Li+ diffusion kinetics due to the existence of oxygen defects, fast Li‐ion conductive coating, and enlarged Li+ layer spacing. As a result, the modified SC‐LLOs showcase superior cyclic stability with a capacity retention of 87.42% after 300 cycles at 1 C and excellent rate performance with a high capacity of 144.9 mAh g−1 at 5 C. This work provides some significant references to strengthen the structural stability of single‐crystal LLOs with long‐term cyclic capability via lattice engineering. [ABSTRACT FROM AUTHOR]

High-temperature sensors for extreme environments are in urgent demand with the rapid development of aerospace, nuclear energy, and advanced manufacturing. Ultrasonic temperature sensors (UTS) are widely used in high-temperature sensing due to their high working temperature that approaches the melting point of the acoustic waveguide. Al 2 O 3 single-crystal fiber (SCF), also called sapphire fiber, is a promising candidate for ultrasonic thermometry due to its ultra-high melting point (∼2050 °C), high strength and oxidation resistance. Here, we report for the first time, to the best of our knowledge, large length-diameter ratio sapphire fibers with specific orientations (a -axis, m -axis, and c -axis) have been grown by laser-heated pedestal growth method and applied for ultrasonic temperature sensing. Sapphire fibers exhibit significant acoustic anisotropy, and a -oriented sapphire fiber has a lower acoustic velocity and a greater velocity-temperature variation, leading to higher sensitivity. Moreover, the acoustic velocity of sapphire fiber could be further decreased by doping with Cr ions owing to the enhanced lattice disorder and crystal density. As a result, an improved unit sensitivity of 28.98–52.88 ns°C−1m−1 and a superior resolution of 1.73–0.95 °C have been achieved in the range of 20–1200 °C via a -oriented Cr:Al 2 O 3 SCF-UTS. More importantly, the sensor performance is positively correlated with ambient temperature, accompanied with the high working temperature (∼1800 °C) and excellent stability (∼20 h), demonstrating promising prospects for applications in high-temperature thermometry. This work provides a feasible approach for designing a high-performance UTS based on acoustic anisotropy and lattice engineering. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) represent one of the current research frontiers owing to their low cost, intrinsic safety, environmental friendliness, and other unique features. In the current era, a myriad of investigations are conducted towards the exploration of advanced electrode materials with exceptional energy/power density, superior rate capability, and ultralong cycling life. Notably, vanadium oxides electrode materials have received great attention due to their diversity in chemical compositions and attractive electrochemical properties. In this review, comprehensive and detailed compendium regarding the latest developments and breakthroughs of highly promising vanadium oxides‐based electrode materials for advanced‐performance SIBs are elucidated. The crystal structures, electrochemical performance, structure‐property relationships and sodium storage mechanization of various vanadium oxides are discussed. In addition, further improvement strategies, including lattice engineering, nanostructuring design, surface modification and 3D porous architecting, are summarized. Finally, potential directions of resolving emergent challenges and forward prospects on augmenting the performance of vanadium oxides‐based electrode materials to facilitate their commercial application in SIBs are proposed. This review provides pioneering understanding of vanadium oxides‐based materials and guiding directions for the development viability of future cutting‐edge SIBs. [ABSTRACT FROM AUTHOR]

The electronic structure of halide perovskites is central to their carrier dynamics, enabling the excellent optoelectronic performance. However, the experimentally resolved transient absorption spectra exhibit large discrepancies from the commonly computed electronic structure by density functional theory. Using pseudocubic CsPbI3 as a prototype example, here, it is unveiled with both ab initio molecular dynamics simulations and transmission electron microscopy that there exists pronounced dynamical lattice distortion in the form of disordered instantaneous octahedral tilting. Rigorous first‐principles calculations reveal that the lattice distortion substantially alters the electronic band structure through renormalizing the band dispersions and the interband transition energies. Most notably, the electron and hole effective masses increase by 65% and 88%, respectively; the transition energy between the two highest valence bands decreases by about one half, agreeing remarkably well with supercontinuum transient‐absorption measurements. This study further demonstrates how the resulting electronic structure modulates various aspects of the carrier dynamics such as carrier transport, hot‐carrier relaxation, Auger recombination, and carrier multiplication in halide perovskites. The insights provide a pathway to engineer carrier transport and relaxation via lattice distortion, enabling the promise to achieve ultrahigh‐efficiency photovoltaic devices. [ABSTRACT FROM AUTHOR]

Abstract The electronic structure of halide perovskites is central to their carrier dynamics, enabling the excellent optoelectronic performance. However, the experimentally resolved transient absorption spectra exhibit large discrepancies from the commonly computed electronic structure by density functional theory. Using pseudocubic CsPbI3 as a prototype example, here, it is unveiled with both ab initio molecular dynamics simulations and transmission electron microscopy that there exists pronounced dynamical lattice distortion in the form of disordered instantaneous octahedral tilting. Rigorous first‐principles calculations reveal that the lattice distortion substantially alters the electronic band structure through renormalizing the band dispersions and the interband transition energies. Most notably, the electron and hole effective masses increase by 65% and 88%, respectively; the transition energy between the two highest valence bands decreases by about one half, agreeing remarkably well with supercontinuum transient‐absorption measurements. This study further demonstrates how the resulting electronic structure modulates various aspects of the carrier dynamics such as carrier transport, hot‐carrier relaxation, Auger recombination, and carrier multiplication in halide perovskites. The insights provide a pathway to engineer carrier transport and relaxation via lattice distortion, enabling the promise to achieve ultrahigh‐efficiency photovoltaic devices.

Ru has recently been considered as a promising alternative of Pt toward hydrogen oxidation reaction (HOR) due to its lower price and similar hydrogen binding energy (HBE) in comparison to Pt. Nevertheless, the catalytic performance of Ru toward HOR is far from the satisfaction of practical application. Herein, it is demonstrated that the modification of Ru multi‐layered nanosheet (MLNS) with Ni can significantly promote the HOR performance. In particular, the HOR performance is strongly related to the Ni location on the surface or in the lattice of Ru MLNS. Experimental and theoretical investigations suggest that Ni in the lattice of Ru MLNS (lattice engineering) optimizes the HBE, while Ni species on the surface (surface engineering) decrease the free energy of water formation, as a result of the significantly enhanced HOR performance. The optimal catalyst, where Ni is located both on the surface and in the lattice, displays superior alkaline HOR performance to commercial Pt/C and Ru/C. The present study not only systematically reveals the significance of Ni modification on Ru toward HOR, but also promotes the fundamental researches on catalyst design for fuel cell reactions and beyond. [ABSTRACT FROM AUTHOR]

The effective separation and migration of photogenerated charge carriers in bulk and on the surface of photocatalysts will significantly promote photocatalytic efficiency. However, the synchronous regulation of photocharges on both counts is challenging. Herein, the simultaneous separation of bulk and surface photocharges is conducted to enhance photocatalytic activity by coupling the surface defects and lattice engineering of bismuth oxybromide. The depth-modulated Bi5O7Br ultrathin nanosheets with an abundance of bismuth in the crystal structure increased the internal electric field, which propelled the separation and migration of photocharges from bulk to the surface. Creation of oxygen vacancies (OVs) on the nanosheet surface forms local electric fields, which can stimulate the migration of charges to active sites on the catalyst surface. Therefore, the OV-assembled Bi5O7Br nanosheets demonstrated enhanced photocatalytic degradation efficiency under simulated solar-light illumination. This study proved the possibility of charge governing via electric field modulation based on an integrated strategy. [ABSTRACT FROM AUTHOR]

Over the last three decades, colloidal crystallization has provided an easy-to-craft platform for mesoscale engineering of photonic and phononic crystals. Nevertheless, the crystal lattices achieved thus far with commodity colloids are largely limited to symmetric and densely packed structures, restricting their functionalities. To obtain non-close-packed crystals and the resulting complexity of the available structures, directional binding between "patchy" colloids has been pursued. However, the conventional "patchy" colloids have been restricted to micrometer-scale spherical particles or clusters. In this Mini-Review, we argue that the time has come to widen the scope of the colloidal palette and include particles made using DNA origami. By benefiting from its unprecedented ability to control nanoscale shapes and patch placement and incorporate various nanomaterials, DNA origami enables novel engineering of colloidal crystallization, particularly for photonic and phononic applications. This mini-review summarizes the recent progress on using DNA origami for colloidal crystallization, together with its challenges and opportunities.

Sluggish conversion kinetics of polysulfides during discharge and the severe shuttle effect significantly hinder the practical application of lithium-sulfur (Li-S) batteries. In this work, the lattice engineering strategy of Fe hybridization is employed to manipulate the bulk phase spacing of FeNi 3 (space group Pm3m) intermetallic compounds to adjust the 3d electronic structure, optimizing the adsorption of polysulfides, thereby accelerating the catalytic conversion. As a result, FeNi 2.25 @OC achieves favorable moderate adsorption toward polysulfides. Due to the larger number of electrons occupying the lowest occupied molecular orbital of Li 2 S 4 , the S-S bonds are weakened and broken. Temperature-dependent experiments confirm that FeNi 2.25 @OC exhibits the lowest activation energy and can effectively accelerate the catalytic conversion of polysulfides. The Li-S cell assembled with FeNi 2.25 @OC modified PP separator delivers a high initial discharge specific capacity of 1219.5 mAh g -1 at 0.2 C. Even at a high sulfur loading of 6.06 mg cm -2 and lean electrolyte conditions (6 µL mg -1 ), it can cycle stably for 60 cycles., (© 2024 Wiley‐VCH GmbH.)

Despite the widespread commercialization of LiFePO 4 as cathodes in lithium-ion batteries, the rigid 1D Li-ion diffusion channel along the [010] direction strongly limits its fast charge and discharge performance. Herein, lattice engineering is developed by the planar triangle BO 3 3- substitution on tetrahedron PO 4 3- to induce flexibility in the Li-ion diffusion channels, which are broadened simultaneously. The planar structure of BO 3 3- may further provide additional paths between the channels. With these synergetic contributions, LiFe(PO 4 ) 0.98 (BO 3 ) 0.02 shows the best performance, which delivers the high-rate capacity (66.8 mAh g -1 at 50 C) and long cycle stability (ultra-low capacity loss of 0.003% every cycle at 10 C) at 25 °C. Furthermore, excellent rate performance (34.0 mAh g -1 at 40 C) and capacity retention (no capacity loss after 2500 cycles at 10 C) at -20 °C are realized., (© 2024 Wiley‐VCH GmbH.)

Lead-free layered double perovskite nanocrystals (NCs), i.e., Cs 4 M(II)M(III) 2 Cl 12 , have recently attracted increasing attention for potential optoelectronic applications due to their low toxicity, direct bandgap nature, and high structural stability. However, the low photoluminescence quantum yield (PLQY, <1%) or even no observed emissions at room temperature have severely blocked the further development of this type of lead-free halide perovskites. Herein, two new layered perovskites, Cs 4 CoIn 2 Cl 12 (CCoI) and Cs 4 ZnIn 2 Cl 12 (CZnI), are successfully synthesized at the nanoscale based on previously reported Cs 4 CuIn 2 Cl 12 (CCuI) NCs, by tuning the M(II) site with different transition metal ions for lattice tailoring. Benefiting from the formation of more self-trapped excitons (STEs) in the distorted lattices, CCoI and CZnI NCs exhibit significantly strengthened STE emissions toward white light compared to the case of almost non-emissive CCuI NCs, by achieving PLQYs of 4.3% and 11.4% respectively. The theoretical and experimental results hint that CCoI and CZnI NCs possess much lower lattice deformation energies than that of reference CCuI NCs, which are favorable for the recombination of as-formed STEs in a radiative way. This work proposes an effective strategy of lattice engineering to boost the photoluminescent properties of lead-free layered double perovskites for their future warm white light-emitting applications., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)

The supercapacitor-diode (CAPode) is a device that integrates the functionality of an ionic diode with that of a conventional supercapacitor. The unique combination of energy storage and rectification properties in CAPodes is relevant for iontronics, alternate current rectifiers, logic operations, grid stabilization, and even biomedical applications. Here, we propose a novel aqueous-phase supercapattery-diode with excellent energy storage [total specific capacity ( C T ) = 162 C g -1 , energy density = 34 W h kg -1 at 1.0 A g -1 ] as well as rectifying properties [rectification ratio I (RR I ) of 23, and rectification ratio II (RR II ) of 0.98]; the unidirectional energy storage is achieved by the utilization of an ion-selective redox reaction of battery-type layered double hydroxide (LDH) nanosheets serving as the electroactive material as well as asymmetric device configuration of supercapattery-diode in the KOH electrolyte. This work expands the types of CAPodes and importantly exemplifies the significance of integrating battery-type LDH and their redox chemistry, allowing a simultaneous increase in charge storage and rectification properties.

Innovative surfaces via lattice engineering are crucial challenges and critical to enhance the mechanical and functional properties of advanced materials. Here, a universal linear scaling rule in terms of key property parameters (KPPs) is proposed to estimate the modifications of local lattice strain (LLS) caused by the surface, in which the bulk modulus (B), the B/G ratio, and the bond energy are utilized to describe the KPPs of the BCC and FCC, the isotropic HCP, and the polarized A 2 B 2 O 7 -type Pyrochlore, individually. The modified broken-bond model by the Hook's law is addressed to predict the elastic-energy-corrected surface energy efficiently and precisely, which is capable to deal with the complex of geometry, chemistry, charge states of clean surface and are verified and validated in 28 metals and ceramics. While the LLS of metals is caused by the improved bond length, the ceramics one is yielded by the reduced one of polarized surface. [ABSTRACT FROM AUTHOR]

Developing sacrificial cathode prelithiation technology to compensate for active lithium loss is vital for improving the energy density of lithium-ion battery full-cells. Li 2 CO 3 owns high theoretical specific capacity, superior air stability, but poor conductivity as an insulator, acting as a promising but challenging prelithiation agent candidate. Herein, extracting a trace amount of Co from LiCoO 2 (LCO), a lattice engineering is developed through substituting Li sites with Co and inducing Li defects to obtain a composite structure consisting of (Li 0.906 Co 0.043 ▫ 0.051 ) 2 CO 2.934 and ball milled LiCoO 2 (Co-Li 2 CO 3 @LCO). Notably, both the bandgap and Li─O bond strength have essentially declined in this structure. Benefiting from the synergistic effect of Li defects and bulk phase catalytic regulation of Co, the potential of Li 2 CO 3 deep decomposition significantly decreases from typical >4.7 to ≈4.25 V versus Li/Li + , presenting >600 mAh g -1 compensation capacity. Impressively, coupling 5 wt% Co-Li 2 CO 3 @LCO within NCM-811 cathode, 235 Wh kg -1 pouch-type full-cell is achieved, performing 88% capacity retention after 1000 cycles., (© 2023 Wiley‐VCH GmbH.)

Metallene materials with atomic thicknesses are receiving increasing attention in electrocatalysis due to ultrahigh surface areas and distinctive surface strain. However, the continuous strain regulation of metallene remains a grand challenge. Herein, taking advantage of autocatalytic reduction of Cu 2+ on biaxially strained, carbon-intercalated Ir metallene, we achieve control over the carbon extraction kinetics, enabling fine regulation of carbon intercalation concentration and continuous tuning of (111) in-plane (-2.0%-2.6%) and interplanar (3.5%-8.8%) strains over unprecedentedly wide ranges. Electrocatalysis measurements reveal the strain-dependent activity toward hydrogen evolution reaction (HER), where weakly strained Ir metallene (w-Ir metallene) with the smallest lattice constant presents the highest mass activity of 2.89 A mg -1 Ir at -0.02 V vs reversible hydrogen electrode (RHE). Theoretical calculations validated the pivotal role of lattice compression in optimizing H binding on carbon-intercalated Ir metallene surfaces by downshifting the d -band center, further highlighting the significance of strain engineering for boosted electrocatalysis.

Lattice engineering of nanomaterials holds promise in simultaneously regulating their geometric and electronic effects to promote their performance. However, local microenvironment engineering of Fe 0 nanoparticles (nFe 0 ) for efficient and selective environmental remediation is still in its infancy and lacks deep understanding. Here, we present the design principles and characterization techniques of lattice-doped nFe 0 from the point of view of microenvironment chemistry at both atomic and elemental levels, revealing their crystalline structure, electronic effects, and physicochemical properties. We summarize the current knowledge about the impacts of doping nonmetal p-block elements, transition-metal d-block elements, and hybrid elements into nFe 0 crystals on their local coordination environment, which largely determines their structure-property-activity relationships. The materials' reactivity-selectivity trade-off can be altered via facile and feasible approaches, e.g., controlling doping elements' amounts, types, and speciation. We also discuss the remaining challenges and future outlooks of using lattice-doped nFe 0 materials in real applications. This perspective provides an intuitive interpretation for the rational design of lattice-doped nFe 0 , which is conducive to real practice for efficient and selective environmental remediation.

Abstract: The ability to manipulate the metal–insulator transition (MIT) of metal oxides is of critical importance for fundamental investigations of electron correlations and practical implementations of power efficient tunable electrical and optical devices. Most of the existing techniques including chemical doping and epitaxial strain modification can only modify the global transition temperature, while the capability to locally manipulate MIT is still lacking for developing highly integrated functional devices. Here, lattice engineering induced by the energetic noble gas ion allowing a 3D local manipulation of the MIT in VO2 films is demonstrated and a spatial resolution laterally within the micrometer scale is reached. Ion‐induced open volume defects efficiently modify the lattice constants of VO2 and consequently reduce the MIT temperature continuously from 341 to 275 K. According to a density functional theory calculation, the effect of lattice constant variation reduces the phase change energy barrier and therefore triggers the MIT at a much lower temperature. VO2 films with multiple transitions in both in‐plane and out‐of‐plane dimensions can be achieved by implantation through a shadow mask or multienergy implantation. Based on this method, temperature‐controlled VO2 metasurface structure is demonstrated by tuning only locally the MIT behavior on the VO2 surfaces. [ABSTRACT FROM AUTHOR]

Pd is a versatile catalyst in various hydrogen-related catalytic applications; however, it typically exhibits low activity in electrocatalytic hydrogen evolution reaction (HER) as too strong Pd-H bonding makes the electronic desorption of H adatoms (H ad ) hardly occur. We herein report a selective etching-deposition approach to implant trace Pd atoms in the near-surface region of Ag nanocrystals, forming a heteratomic-rich Pd-Ag structure on Ag surface. This near-surface dilution of Pd atoms can dramatically facilitate the electronic desorption of H ad . As a result, this approach enhances the electrocatalytic HER activity of Pd catalysts about 14 times with excellent performance durability, approaching the high level of Pt catalysts. While enhancing the catalytic performance, this atomic implantation strategy allows the substantial reduction of material costs. This work thus represents a step toward the high-performance, low-cost catalyst design through near-surface lattice engineering. [ABSTRACT FROM AUTHOR]

Mainstream non-volatile memory (NVM) devices based on floating gate structures or phase-change/ferroelectric materials face inherent limitations that compromise their suitability for long-term data storage. To address this challenge, a novel memory device based on light-programmed lattice engineering of thin rhenium disulfide (ReS 2 ) flakes is proposed. By inducing sulfur vacancies in the ReS 2 channel through light illumination, the device's electrical conductivity is modified accordingly and multiple conductance states for data storage therefore are generated. The device exhibits more than 128 distinct states with linearly increasing conductance, corresponding to a sevenfold increase in storage density. Through further optimization to achieve atomic-level precision in defect creation, it is possible to achieve even higher storage densities. These states are extremely stable in vacuum or inert ambient showing long retention of >10 years, while they can be erased upon exposure to the air. The ReS 2 memory device can maintain its stability over multiple program-erase operation cycles and shows superior wavelength discrimination capability for incident light in the range of 405-785 nm. This device represents a significant contribution to NVM technology by offering the ability to store information in multistate memory and enabling filter-free color image recorder applications., (© 2023 Wiley-VCH GmbH.)

Porous Cu-CoS x nanosheets arrays arranged on Ni foam (Cu-CoS x /NF) are constructed by a hydrothermal strategy assisted with sulfur vapor etching, which displays a high alkaline HER performance. The introduction of low valence copper induces the lattice contraction of CoS x , it not only brings the enrichment of electron cloud density to nearly Co active sites, but also optimizes the kinetics of hydrogen evolution and the adsorption behaviors of reactants, which promotes the catalytic performance of alkaline HER and Zn-H 2 O cell. [Display omitted] • Doping of Cu species induces lattice contraction of CoS x , which obviously optimizes the electronic structure. • Porous Cu-CoS x /NF nanosheets arrays displays high HER activity and robust stability. • Porous Cu-CoS x /NF nanosheets arrays based Zn-H 2 O cell is assembled to realize lighting. Design and development of high-performance non-precious electrocatalysts for clean and renewable energy production remain huge challenging. In this work, porous cobalt sulfide nanosheets arrays with low valence copper incorporated supported on nickel foam (Cu-CoS x /NF) is constructed by a hydrothermal strategy assisted with sulfur vapor etching. which exhibits admirable alkaline hydrogen evolution activity with the low overpotentials of 75 and 203 mV at 10 and 300 mA cm−2, respectively, leading to high performance in alkaline HER than those of reported cobalt sulfide-based catalysts and even outperforms Pt/C at high current density. The introduction of low valence copper induces the lattice contraction of CoS x , resulting in the enrichment of electron cloud density nearly at Co active sites, and thereby optimizing the kinetics of hydrogen evolution and the adsorption behaviors of reactants, therefore, elevating the electrocatalytic activities. Furthermore, the synthesized Cu-CoS x /NF catalyst acted as the cathode in alkaline Zn-H 2 O cell demonstrating the potential applications of the newly developed hydrogen evolution catalyst. This work would shed light on more in-depth insight into doping of metal species-induced lattice contraction in the design of outstanding electrocatalysts. [ABSTRACT FROM AUTHOR]

Copper sulfides have been recognized as one of the most promising cathode materials for rechargeable magnesium batteries due to their large theoretical capacity and unique conversion-type mechanism. However, the solid-state diffusion of bivalent Mg2+ ions in CuS host lattice is subjected to huge electrostatic interaction and thus sluggish kinetics. Herein, anion substitution strategy and crystal engineering are reported to regulate electrochemical reaction kinetics and reinforce magnesium storage performances of tubular CuS cathodes. Benefitting from anion substitution and crystal facet regulation, the lattice well-exposed Se-substituted CuS nanotube cathodes demonstrate excellent magnesium storage capacity (372.9 mAh g−1 at 100 mA g−1), remarkable cycling stability (1600 cycles at 2.0 A g−1), and a good rate capability (112.4 mAh g−1 at 2.0 A g−1). Electrochemical kinetics investigation further suggests that anionic Se-substitution and crystal facet regulation can significantly optimize electrochemical reaction kinetics and accelerate diffusion rate of Mg2+ ions. Ex-situ X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) characterizations reveal the conversion reaction mechanism of Se-substituted CuS cathodes. These novel findings provide an effective approach to construct high-performance cathode materials for rechargeable magnesium batteries and hold great promise for development of other new battery systems. The optimized kinetics of CuS nanotubes are realized via high-efficiency anion substitution strategy and crystal engineering. The overall Mg 2+ storage properties , reversible capacity, rate capability and cycling stability, are almost the best among the published similar cathode materials. [Display omitted] • The lattice well-exposed Se-substituted CuS nanotubes are fabricated. • The overall Mg 2+ storage property is almost the best among the published cathode. • Weaker polarization and higher Mg 2+ mobility are realized by rational regulation. • The multistep reaction kinetics of the Se-doping CuS nanotube cathode are confirmed. [ABSTRACT FROM AUTHOR]

Designing irregular but desirable atomic arrangements in crystal lattices of solids can greatly change their intrinsic physical properties beyond expectations from common doping and alloying. However, structures of solids are generally determined by thermodynamic preferences during solid-state reactions, strictly restricting delicate atomic-level lattice engineering. Here, we report a new strategy of realizing desirable defect architecture in a highly predictable way to control thermal and charge transport properties of solids. Introducing unusually high concentration indium to the tetragonal chalcopyrite CuFeS 2 to form the Cu 1− x In x FeS 2 (x = 0–0.12) system stabilizes the highly unusual local structure, namely, high-temperature polymorph of cubic zinc blende structure in the surrounding matrix and displaced In+ cation with 5s2 lone pair electrons from the Cu+ sublattice. This substantially suppresses notoriously high lattice thermal conductivity of tetrahedrally networked CuFeS 2 to record-low values ~0.79 W m−1 K−1 at 723 K through multiscale scattering and softening mechanisms of heat-carrying phonon, approaching its theoretical lower limit. Consequently, one of the highest thermoelectric figures of merit, ZT, among chalcopyrite sulfides is achieved. Our design principle utilizes standard potentials and ionic radius of constituent elements, thereby readily applicable to designing various classes of solids. Remarkably, we directly imaged the atomic-level structure of positional disorder stabilizing the high-temperature phase and off-centered In+ from the ideal position employing a scanning transmission electron microscope. This observation shows how our material design strategy works, and provides important understanding for how local structures in solids form when either compatible or incompatible atoms are introduced to the crystal lattices. [Display omitted] • Design of atomic-level lattice engineering by thermodynamic consideration. • High-temperature polymorph for chalcopyrite is unprecedentedly stabilized at RT. • Direct observation of atomic-level defect structures. • Severe positional disorder coupled with phonon softening reduces κ L dramatically. • Record-low κ L for chalcopyrite sulfide is achieved at ~0.79 W m−1 K−1. [ABSTRACT FROM AUTHOR]

Abstract: A coordination chemistry and lattice engineering study of 10 new Cu(II) compounds with the ligands N-(pyridin-2-yl)acetamide (Haap) and N-(pyrimidin-2-yl)acetamide (Haapm) with the general formula Cu(LL)2(anion)2 is described. The bidentate ligands bind in a N,O-chelating mode and the used anions are , , , , Cl−. For five of the compounds a 3D crystal and molecular structure analysis has been performed. All Cu(II) ions have a tetragonal-based geometry; the basal plane of each copper consists of a N and an O atom of two different bischelating N,O-donor ligands; Cu–N distances vary from 2.00 to 2.04Å and Cu–O distances are between 1.93 and 1.96Å, whereas the apical sites are occupied by an atom of the anions, thereby providing an elongated octahedral geometry (Cu–anion contacts are between 2.41 and 2.81Å). The intermolecular interactions are all involving multiple H-bond systems, providing a 2D polymeric array for most of the compounds. The chloride compound forms a zigzag polymeric array of hydrogen bonds. Most surprisingly, the non-coordinating pyrimidine nitrogen atom, does not take part in any lattice hydrogen bonding. [Copyright &y& Elsevier]

Abstract: Progress in lattice engineering, planar ultra-strained epitaxial layer growth, and layer transfer technology has resulted in the ability to create many engineered substrate types. In particular, a wealth of possibilities exists in the SiGe/Si system. Engineered substrates based on relaxed SiGe layers on Si with strained Si and Ge layers have resulted in long channel MOSFETs with ∼2× enhancement in NMOS drive current and more than 10× enhancement in PMOS drive current as compared to control Si MOSFETs. We have attempted to increase the NMOS drive current further by beginning to explore strained GaAs on relaxed SiGe layers on Si. [Copyright &y& Elsevier]

• We synthesized single phase Mn 1.15 Fe 0.85 P 0.55 Si 0.45-x Al x polycrystalline bulk sample using conventional solid state reaction. • The curie temperature can be systematically tuned by substitution of Al at Si-site due to the lattice engineering effect. • We found the inverse relationship between the curie temperature and the lattice constant ratio (a / c). [Display omitted] Bulk polycrystalline samples of hexagonal Fe 2 P-type Al-added Mn 1.15 Fe 0.85 P 0.55 Si 0.45 were prepared via a solid-state reaction under controlled heat treatment, and their magnetocaloric properties, including magnetization and entropy change, were investigated. Notably, the Curie temperature, which is directly related to the operating temperature of magnetocaloric materials, could be systematically tuned through Al substitution at Si sites owing to the lattice engineering effect. We found an inverse relationship between the Curie temperature and the ratio of the c -axis lattice constant to a -axis lattice constant, which enables the design of magnetocaloric materials for high-performance magnetic cooling systems. [ABSTRACT FROM AUTHOR]

Intrinsic structural degradation and unstable surface chemical properties are bottlenecks of the Ni-rich cathode material for commercial application, which mainly originates from the lattice distortion and residual lithium. In this work, an effective molybdenum lattice engineering method to simultaneously enhance the intrinsic structural stability and the surface chemical properties of LiNi0.9Co0.05Mn0.05O2 cathode material is developed. The molybdenum on transition-metal sites visibly alleviates lattice distortion initiating microcracks by anchoring in the crystal lattice, meanwhile, the interface chemical stability is also significantly improved by consuming residual lithium to form the lithium molybdate oxide fast ion conductor coating layer. Therefore, the molybdenum-modified LiNi0.9Co0.05Mn0.05O2 delivers a remarkable Li+ storage functionalities (202.8 mAh g−1 with 90% capacity retention after 100 cycles), much higher than the pristine LiNi0.9Co0.05Mn0.05O2 (78% capacity retention after 100 cycles). In addition, the Density-Functional Theory (DFT) calculations announce that the Li+ migration the energy barrier of molybdenum-modified LiNi0.9Co0.05Mn0.05O2 is decreased, thus showing an ultrahigh discharge capacity of 166.4 mAh g−1 even at 8C rate. This strategy is very promising to provide a new insight into lattice engineering of cations doping effect, highlight the importance of lattice engineering in optimizing their energy functionalities. [Display omitted] [ABSTRACT FROM AUTHOR]

ReS 2 exhibits strong anisotropic optical and electrical responses originating from the asymmetric lattice. Here, we show that the anisotropy of monolayer (1L) ReS 2 in optical scattering and electrical transport can be practically erased by lattice engineering via lithium (Li) treatment. Scanning transmission electron microscopy revealed that significant strain is induced in the lattice of Li-treated 1L-ReS 2 , due to high-density electron doping and the resultant formation of continuous tiling of nanodomains with randomly rotating orientations of 60°, which produced a nearly isotropic response of polarized Raman scattering and absorption of Li-treated 1L-ReS 2 . With Li treatment, the in-plane conductance of 1L-ReS 2 increased by an order of magnitude, and its angle dependence became negligible. Our result that the asymmetric phase was converted into the isotropic phase by electron injection could significantly expand the optoelectronic applications of polymorphic two-dimensional transition metal dichalcogenides.

An effective lattice engineering method to simultaneously control the defect structure and the porosity of layered double hydroxides (LDHs) was developed by adjusting the elastic deformation and chemical interactions of the nanosheets during the restacking process. The enlargement of the intercalant size and the lowering of the charge density were effective in increasing the content of oxygen vacancies and enhancing the porosity of the stacked nanosheets via layer thinning. The defect-rich Co-Al-LDH-NO 3 - nanohybrid with a small stacking number exhibited excellent performance as an oxygen evolution electrocatalyst and supercapacitor electrode with a large specific capacitance of ∼2230 F g -1 , which is the largest capacitance of carbon-free LDH-based electrodes reported to date. Combined with the results of density functional theory calculations, the observed excellent correlations between the overpotential/capacitance and the defect content/stacking number highlight the importance of defect/stacking structures in optimizing the energy functionalities. This was attributed to enhanced orbital interactions with water/hydroxide at an increased number of defect sites. The present cost-effective lattice engineering process can therefore provide an economically feasible methodology to explore high-performance electrocatalyst/electrode materials.-1 , which is the largest capacitance of carbon-free LDH-based electrodes reported to date. Combined with the results of density functional theory calculations, the observed excellent correlations between the overpotential/capacitance and the defect content/stacking number highlight the importance of defect/stacking structures in optimizing the energy functionalities. This was attributed to enhanced orbital interactions with water/hydroxide at an increased number of defect sites. The present cost-effective lattice engineering process can therefore provide an economically feasible methodology to explore high-performance electrocatalyst/electrode materials.

The ultimate performance of a solid state device is limited by the restricted number of crystalline substrates that are available for epitaxial growth. As a result, only a small fraction of semiconductors are usable. This study describes a novel concept for a tunable compliant substrate for epitaxy, based on a graphene-porous silicon nanocomposite, which extends the range of available lattice constants for epitaxial semiconductor alloys. The presence of graphene and its effect on the strain of the porous layer lattice parameter are discussed in detail and new remarkable properties are demonstrated. These include thermal stability up to 900 °C, lattice tuning up to 0.9 % mismatch, and compliance under stress for virtual substrate thicknesses of several micrometers. A theoretical model is proposed to define the compliant substrate design rules. These advances lay the foundation for the fabrication of a compliant substrate that could unlock the lattice constant restrictions for defect-free new epitaxial semiconductor alloys and devices., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)