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The strain‐driven morphotropic boundary in BiFeO3 can enhance the piezoelectric properties. However, the tetragonal phase has generally been observed in BiFeO3 films grown on substrates with intense compressive strain (more than −4.5%) within a limited thickness range (<300 nm) due to significant thickness‐dependent strain relaxation during film growth at high deposition temperatures. This work proposes suppressing thickness‐dependent strain relaxation by decreasing growth temperature. Utilizing a hydrothermal method, the growth temperature of epitaxial BiFeO3 films decreases to 200 °C. As a result, the tetragonal phase is observed in 600‐nm‐thick BiFeO3 film on (001) SrTiO3 substrates (strain equals only −1.5%), accompanied by the monoclinic phase. This SrTiO3‐available morphotropic phase boundary significantly enhances the piezoelectric response (d33,f′=110pmV−1)$ {({d}^{\prime}_{\rm 33,f} = 110\, {\rm pm\, V}^{-1})} $ in epitaxial BiFeO3 film. Ex situ and in situ measurements, theoretical calculations, and simulation confirm that the SrTiO3‐available morphotropic phase boundary originates from the suppressed strain relaxation. Furthermore, a critical temperature (400 °C), below which the tetragonal phase can be maintained, is identified to offer an applicable strategy for extending strain‐driven morphotropic phase boundary for high‐performance piezoelectric films. [ABSTRACT FROM AUTHOR]

Background: Achieving cost-competitiveness remains challenging for industrial biomanufacturing. With whole-cell biocatalysis, inefficiency presents when individual cells vary in their production levels. The problem exacerbates when the basis for such production heterogeneity is heritable. Here, evolution selects for the low- and non-producers, as they have lowered/abolished the cost of bioproduction to fitness. With the scale of population expansion required for industrial bioproduction, the asymmetrical enrichment can be severe enough to compromise the performance, and hence commercial viability of the bioprocess. Clearly, addressing production heterogeneity is crucial, especially in improving the stability of bioproduction across the cell generations. In this respect, we designed a growth-coupling strategy for terpenoid bioproduction in Escherichia coli. By knocking out the native 1-deoxy-D-xylulose 5-phosphate reductoisomerase (dxr) gene and introducing the heterologous mevalonate pathway, we created a chassis that relies solely on the latter for synthesis of all terpenoids. We hypothesise that the need to sustain the biosynthesis of endogenous life-sustaining terpenoids will impose a minimum level of productivity, which concomitantly improves the bioproduction of our target terpenoid. Results: Following the confirmation of lethality of a dxr knockout, we challenged the strains with a continuous plasmid-based bioproduction of linalool. The Δdxr strain achieved an improved productivity profile in the first three days post-inoculation when compared to the parental strain. Productivity of the Δdxr strain remained observable near the end of 12 days, and after a disruption in nutrient and oxygen supply in a separate run. Unlike the parental strain, the Δdxr strain did not evolve the same deleterious mutations in the mevalonate pathway, nor a viable subgroup that had lost its resistance to the antibiotic selection pressure (a plausible plasmid loss event). We believe that this divergence in the evolution trajectories is indicative of a successful growth-coupling. Conclusion: We have demonstrated a proof of concept of a growth-coupling strategy that improves the performance, and stability of terpenoid bioproduction across cell generations. The strategy is relatively broad in scope, and easy to implement in the background as a 'fail-safe' against a fall in productivity below the imposed minimum. We thus believe this work will find widespread utility in our collective effort towards industrial bioproduction. [ABSTRACT FROM AUTHOR]

All‐optical magnetization reversal provides a low‐power approach for investigating spin state manipulation in 2D magnets. However, the ambient observation of photomagnetic coupling presents significant challenges due to the low Curie temperatures exhibited by most 2D magnets. Herein, a mixed‐dimensional heterostructure comprising a surface‐oxidized Fe3GeTe2 nanosheet with enhanced magnetic properties and individual semiconducting ZnO nanorod is proposed to explore proximity photomagnetic modulation and spin‐enhanced photodetection behaviors. The surface curvature of ZnO nanorod induces pronounced strains for Fe3GeTe2 nanosheet, leading to its anomalous Raman polarization and spin ordering at room temperature. Strain‐activated itinerant spin electrons are immobilized on the O‐2p orbitals of adjacent ZnO, thereby facilitating the optical demagnetization process in Fe3GeTe2 without aid of magnetic field. First‐principles calculations together with in situ characterization experiments further confirm that the primary charge transfer channel involves coupling between Fe3+ and oxygen vacancy defects anchored at heterointerfaces. The rapid establishment of magnetization by illumination in ZnO nanorod contributes to spin‐tunneling‐enhanced photocurrent, device response dynamics, polarization detection and ultraviolet imaging capability. These findings offer valuable insights to optimize the optoelectronic properties of conventional semiconductors and advance complex dimensional spin‐optoelectronic devices. [ABSTRACT FROM AUTHOR]

Clavulanic acid is a potent β-lactamase inhibitor produced by Streptomyces clavuligerus, widely used in combination with β-lactam antibiotics to combat antimicrobial resistance. This systematic review analyzes the most successful methodologies for clavulanic acid overproduction, focusing on the highest yields reported in bench-scale and bioreactor-scale fermentations. Studies have demonstrated that glycerol is the preferred carbon source for clavulanic acid production over other sources like starch and dextrins. The optimization of feeding strategies, especially in fed-batch operations, has improved glycerol utilization and extended the clavulanic acid production phase. Organic nitrogen sources, particularly soybean protein isolates and amino acid supplements such as L-arginine, L-threonine, and L-glutamate, have been proven effective at increasing CA yields both in batch and fed-batch cultures, especially when balanced with appropriate carbon sources. Strain engineering approaches, including mutagenesis and targeted genetic modifications, have allowed for the obtainment of overproducer S. clavuligerus strains. Specifically, engineering efforts that overexpress key regulatory genes such as ccaR and claR, or that disrupt competing pathways, redirect the metabolic flux towards CA biosynthesis, leading to high clavulanic acid titers. The fed-batch operation at the bioreactor scale emerges as the most feasible alternative for prolonged clavulanic acid production with both wild-type and mutant strains, allowing for the attainment of high titers during cultivations. [ABSTRACT FROM AUTHOR]

In this paper, a strain-modified Si/Si0.97C0.03 asymmetrical superlattice exotic type (p + -i-p-n +) avalanche photodetector has been designed for applications on the infrared wavelength region. The photoelectric characteristics of the device are studied by developing a self-consistent quantum phenomena-based drift–diffusion model in conjunction with PSpice simulator. The overall performance of the device has been boosted significantly by introducing strain engineering which enhances the out-plane mobility of the charge particles in the intrinsic/active region of the device. The strain is produced in the intrinsic/active region by inclusion of small amount of carbon (C) into the pure Si material. The proposed strain-modified exotic avalanche photodetector exhibits better performance in terms of quantum efficiency (0.671) and photo-responsivity (0.645 A/W) compared to its planer unstrained Si counterpart (quantum efficiency: 0.481, photo-responsivity: 0.524A/W) at 1800 nm wavelength. Additionally, a 3 × 4 array of photodetectors has been designed using this device and its optoelectronic properties are studied in the IR wavelength region. The superiority of the performance of the 3 × 4 array of photodetectors is established in terms of better quantum efficiency (0.872) and better photo-responsivity (0.851 A/W). The validity of quantum phenomena-based drift–diffusion model is established by comparing the simulated data with experimental findings under similar operating conditions. The developed device can be used in defense as well as biomedical industries for sensing applications. [ABSTRACT FROM AUTHOR]

Two-dimensional WSi2X4 (X = N, P, As) has stimulated extensive studies due to its structural diversity and intriguing properties. Here, a systematic study on the strain engineering of electronic and optical properties in monolayer WSi2X4 is presented. Our results demonstrate that the monolayer WSi2X4 can withstand biaxial tensile strains of 13.1%, 16.3%, and 12.2% for X = N, P, and As, respectively, while the corresponding critical stresses are 27.90 GPa, 14.58 GPa,and 13.56 GPa, respectively. Furthermore, the bandgap of monolayer WSi2X4 can undergo a direct-to-indirect transition and even achieve a semiconductor-to-metal transition under appropriate biaxial strains. In addition, the light absorption of monolayer WSi2X4 in the visible region can be effectively improved by tensile strain, and the red (blue) shift of the absorption peak can be observed by tensile (compression) strain. The results show that monolayer WSi2X4 exhibits outstanding mechanical strength and physical properties, which is promising for future optoelectronic devices. [ABSTRACT FROM AUTHOR]

Maximizing the production of heterologous biomolecules is a complex problem that can be addressed with a systems-level understanding of cellular metabolism and regulation. Specifically, growth-coupling approaches can increase product titers and yields and also enhance production rates. However, implementing these methods for non-canonical carbon streams is challenging due to gaps in metabolic models. Over four design-build-test-learn cycles, we rewire Pseudomonas putida KT2440 for growth-coupled production of indigoidine from para-coumarate. We explore 4,114 potential growth-coupling solutions and refine one design through laboratory evolution and ensemble data-driven methods. The final growth-coupled strain produces 7.3 g/L indigoidine at 77% maximum theoretical yield in para-coumarate minimal medium. The iterative use of growth-coupling designs and functional genomics with experimental validation was highly effective and agnostic to specific hosts, carbon streams, and final products and thus generalizable across many systems.

The S-doped PtMn concave cubes enclosed with high index facet and regulatable surface strain are successfully fabricated by two steps hydrothermal method. The PtMnS 1.1 catalyst exhibits superior catalytic properties for ethanol electrooxidation reaction in acidic and alkaline media, which is ascribed to the optimal surface strain and unsaturated surface-active sites. [Display omitted] Surface strain engineering has proven to be an efficient strategy to enhance catalytic properties of platinum (Pt)-based catalysts for electrooxidation reactions. Herein, the S-doped PtMn concave cubes (CNCs) enclosed with high index facets (HIFs) and regulatable surface strain are successfully fabricated by two steps hydrothermal method. The S element with electrophilic property can modify the near-surface of PtMn nanocrystals, altering the electronic structure of Pt to effectively regulate the adsorption/desorption of intermediates in the ethanol electrooxidation reaction (EOR). The PtMnS 1.1 catalyst with optimal surface strain delivered extraordinary catalytic performance on EOR in acidic media, with a specific activity of 2.88 mA/cm2 and mass activity of 1.10 mA/μg Pt , which is 4.1 and 2.2 times larger than that of state-of-the-art Pt/C catalyst, respectively. Additionally, the PtMnS 1.1 catalyst also achieve excellent catalytic properties in alkaline electrolyte for EOR. The results of kinetic studies indicated that the surface strain and modified electronic structure can degrade the activation energy barrier during the process of EOR, which is beneficial for enhance the reaction rate. This work provides a promising approach to construct highly efficient electrocatalysts with tunable surface strain effects for clean energy electro-chemical reactions. [ABSTRACT FROM AUTHOR]

Single-photon detections (SPDs) represent a highly sensitive light detection technique capable of detecting individual photons at extremely low light intensity levels. This technology mainly relies on the mainstream SPDs, such as photomultiplier tubes (PMTs), avalanche photodiodes (SAPD), superconducting nanowire single-photon detectors (SNSPDs), superconducting transition-edge sensor (TES), and hybrid lead halide perovskite. However, the complexity and high manufacturing cost, coupled with the requirement of special conditions like a low-temperature environment, pose significant challenges to the wide adoption of SPDs. To address the challenges faced by SPDs, significant efforts have been devoted to enhancing their performance. In this review, we first summarize the principles and technical challenges of several SPDs. Conductors, superconductors, semiconductors, 3D bulk materials, 2D film materials, 1D nanowires, and 0D quantum dots have all been discussed for single-photon detectors. Methods such as special optical structure, waveguide integration, and strain engineering have been employed to elevate the performance of single-photon detectors. These techniques enhance light absorption and modulate the band structure of the material, thereby improving the single-photon sensitivity. By providing an overview of the current situation and future challenges of SPDs, this review aims to propose potential solutions for photon detection technology. [ABSTRACT FROM AUTHOR]

Single-photon emitters (SPEs) hold the key to many quantum technologies including quantum computing. In particular, developing a scalable array of identical SPEs can play an important role in preparing single photons – crucial resources for computation – at a high rate, allowing to improve the computational capacity. Recently, different types of SPEs have been found in various 2D materials. Towards realizing scalable SPE arrays in 2D materials for quantum computation, it is required to develop tunable SPEs that can produce identical photons by precisely controlling emission properties. Here, we present a brief review of the recent progress on various tuning methods in different 2D materials. Firstly, we discuss the operation principle of different 2D SPEs along with their unique characteristics. Secondly, we introduce various dynamic strain engineering methods for tuning the emission wavelengths in 2D SPEs. We also present several electric field-induced wavelength tuning methods for 2D SPEs. Lastly, we discuss the outlook of dynamically tunable 2D SPEs towards scalable 2D SPE arrays for realizing practical quantum photonics applications.

The photoconversion of CO2 into valuable chemical products using solar energy is a promising strategy to address both energy and environmental challenges. However, the strongly adsorbed CO2 frequently impedes the seamless advancement of the subsequent reaction by significantly increasing the reaction activation energy. Here, we present a BiFeO3 material with lattice strain that collaboratively regulates the d/p‐2π* orbitals hybridization between metal sites and *CO2 as well as *COOH intermediates to achieve rapid conversion of solidly adsorbed CO2 to critical *COOH intermediates, accelerating the overall CO2 reduction kinetics. Quasi in situ X‐ray photoelectron spectroscopy and in situ Fourier Transform infrared spectroscopy combined with theoretical calculation reveals that the optimized Fe sites enhance the adsorption and activation effect of CO2, and continuous internal electrons are rapidly transferred to the reaction sites and injected into the surface *CO2 and *COOH under the condition of illumination, which promotes the rapid formation and stability of *COOH. Certainly, the performance of CO2 photoreduction to CO is improved by 12.81‐fold compared with the base material. This work offers a new perspective for the rapid photoreduction process of strongly adsorbed CO2. [ABSTRACT FROM AUTHOR]

It is significant to modulate the bandgap of crystalline silicon (c‐Si) by applying large strains on it through controlled stretch. However, investigations on the stretchability of c‐Si are still insufficient, especially for samples with feature sizes in the submicron to micron scale. In this work, the large stretchability of silicon wires with submicron to micron diameters (SiMWs) is reported for the first time by using vapor–liquid–solid grown ultralong SiMWs. The diameters of the SiMW specimens range from 400 nm to 1.8 μm. The loading speed for stretching SiMWs is 100 nm s−1. It is found that the SiMWs with micron diameter have a stretch limit over 10%, while the stretch limit for samples with submicron diameter can reach 12%. The results fill the gaps in the knowledge of micron‐scale silicon materials' stretchability. The average Young's modulus of SiMWs is measured as 115 GPa. Cyclic loading tests indicate that the tensile deformation of SiMWs is elastic and reversible with no plastic deformation observed. In this work, it is shown that large stretch of SiMWs can be achieved without the need of harsh experimental conditions, which will greatly facilitate the study of large strain engineering on c‐Si to modulate their properties and broaden their applications. [ABSTRACT FROM AUTHOR]

The low-dimensional light source shows promise in photonic integrated circuits. Stable layered van der Waals material that exhibits luminescence in the near-infrared optical communication waveband is an essential component in on-chip light sources. Herein, the tunable near-infrared photoluminescence (PL) of the air-stable layered titanium trisulfide (TiS3) is reported. Compared with iodine particles as a transport agent, TiS3 grown by chemical vapor transport using sulfur powder as a transport agent has fewer sulfur vacancies, which increases the luminescence intensity by an order of magnitude. The PL emission wavelength can be regulated in the near-infrared regime by thickness control. In addition, we observed an interesting anisotropic strain response of PL in layered TiS3 nanoribbon: a blue shift of PL was achieved when the uniaxial tensile strain was applied along the b-axis, while a negligible shift was observed when the strain was applied along the a-axis. Our work reveals the tunable near-infrared luminescent properties of TiS3 nanoribbons, suggesting their potential applications as near-infrared light sources in photonic integrated circuits. [ABSTRACT FROM AUTHOR]

Semiconductor nanowires have inspired plenty of novel nanotechnology device concepts in photonics, electronics, and sensing, owing to their unique functionalities and integrability in heterogeneous platforms. Lattice‐mismatched core/shell heterostructures, in particular, open new avenues for strain engineering and material properties modification. A notable case is the widely tunable tensile strain in the core of GaAs/InxAl1‐xAs core/shell nanowires, which can be used to tailor the GaAs bandgap for applications across near‐infrared, like optical fiber telecommunication, imaging, photovoltaics, etc. As it is shown here, though, the bandgap narrowing under high tensile strain in the GaAs core is accompanied by fast non‐radiative recombination, which is undesirable for any device application. The limiting role of the lattice‐mismatched core/shell interface is revealed, and a novel core/dual‐shell heterostructure that employs an intermediate AlyGa1‐yAs shell (spacer) is proposed. This spacer decouples the GaAs/AlyGa1‐yAs interface, which confines electrons and holes into GaAs, from the lattice‐mismatched AlyGa1‐yAs/InxAl1‐xAs one, whereas the strain in GaAs is unaffected. Choosing the optimal spacer thickness, the photoluminescence yield increases significantly, with longer emission decay lifetimes and slower carrier cooling rates. Besides unlocking the potential of GaAs for photonic applications across near‐infrared, the proposed heterostructure concept can also be adopted for other material systems. [ABSTRACT FROM AUTHOR]

Solar cells represent a promising innovation in energy storage, offering not only exceptional cleanliness and low cost but also a high degree of flexibility, rendering them widely applicable. In recent years, scientists have dedicated substantial efforts to enhancing the performance of solar cells, aiming to drive sustainable development and promote clean energy applications. One approach that has garnered significant attention is strain engineering, which involves the adjustment of material microstructure and organization through mechanical tensile or compressive strain, ultimately serving to enhance the mechanical properties and performance stability of materials. This paper aims to provide a comprehensive review of the latest advancements in the application of strain engineering in solar cells, focused on the current hot research area—perovskite solar cells. Specifically, it delves into the origins and characterization of strain in solar cells, the impact of strain on solar cell performance, and the methods for regulating stable strain. Furthermore, it outlines strategies for enhancing the power conversion efficiency (PCE) and stability of solar cells through strain engineering. Finally, the paper conducts an analysis of the challenges encountered in the development process and presents a forward-looking perspective on further enhancing the performance of solar cells through strain engineering. [ABSTRACT FROM AUTHOR]

The engineering of ferroic orders, which involves the evolution of atomic structure and local ferroic configuration in the development of next‐generation electronic devices. Until now, diverse polarization structures and topological domains are obtained in ferroelectric thin films or heterostructures, and the polarization switching and subsequent domain nucleation are found to be more conducive to building energy‐efficient and multifunctional polarization structures. In this work, a continuous and periodic strain in a flexible freestanding BaTiO3 membrane to achieve a zigzag morphology is introduced. The polar head/tail boundaries and vortex/anti‐vortex domains are constructed by a compressive strain as low as ≈0.5%, which is extremely lower than that used in epitaxial rigid ferroelectrics. Overall, this study c efficient polarization structures, which is of both theoretical value and practical significance for the development of next‐generation flexible multifunctional devices. [ABSTRACT FROM AUTHOR]

Strain engineering is a novel method that can achieve superior performance for different applications. The lattice strain can affect the performance of electrochemical catalysts by changing the binding energy between the surface‐active sites and intermediates and can be affected by the thickness, surface defects and composition of the materials. In this review, we summarized the basic principle, characterization method, introduction strategy and application direction of lattice strain. The reactions on hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are focused. Finally, the present challenges are summarized, and suggestions for the future development of lattice strain in electrocatalytic overall water splitting are put forward. [ABSTRACT FROM AUTHOR]

The evolutions of chip thermal management and micro energy harvesting put forward urgent need for micro thermoelectric devices. Nevertheless, low‐performance thermoelectric thick films as well as the complicated precision cutting process for hundred‐micron thermoelectric legs still remain the bottleneck hindering the advancement of micro thermoelectric devices. In this work, an innovative direct melt‐calendaring manufacturing technology is first proposed with specially designed and assembled equipment, that enables direct, rapid, and cost‐effective continuous manufacturing of Bi2Te3‐based films with thickness of hundred microns. Based on the strain engineering with external glass coating confinement and controlled calendaring deformation degree, enhanced thermoelectric performance has been achieved for (Bi,Sb)2Te3 thick films with highly textured nanocrystals, which can promote carrier mobility over 182.6 cm2 V−1 s−1 and bring out a record‐high zT value of 0.96 and 1.16 for n‐type and p‐type (Bi,Sb)2Te3 thick films, respectively. The nanoscale interfaces also further improve the mechanical strength with excellent elastic modules (over 42.0 GPa) and hardness (over 1.7 GPa), even superior to the commercial zone‐melting ingots and comparable to the hot‐extrusion (Bi,Sb)2Te3 alloys. This new fabrication strategy is versatile to a wide range of inorganic thermoelectric thick films, which lays a solid foundation for the development of micro thermoelectric devices. [ABSTRACT FROM AUTHOR]

Polar topological structures in ferroelectric materials have attracted significant interest due to their fascinating physical properties and promising applications in high‐density, nonvolatile memories. Currently, most polar topological patterns are only observed in the bulky perovskite superlattices. In this work, a discovery of tunable ferroelectric polar topological structures is reported, designed, and achieved using topological strain engineering in two‐dimensional (2D) PbX (X = S, Se, and Te) materials via integrating first‐principles calculations, machine learning molecular dynamics simulations, and continuum modeling. First‐principles calculations discover the strain‐induced reversible ferroelectric phase transition with diverse polarization directions strongly correlated to the straining conditions. Taking advantage of the mechanical flexibility of 2D PbX, using molecular dynamics (MD) simulations, it is successfully demonstrated that the complex strain fields of 2D topological surfaces under mechanical indentation can generate unique skyrmion‐like polar topological vortex patterns. Further continuum simulations for experimentally accessible larger‐scale 2D topological surfaces uncover multiple skyrmion‐like structures (i.e., vortex, anti‐vortex, and flux‐closure) and transition between them by adopting/designing different types of mechanical loadings (such as out‐of‐plane indention and air blowing). Topological surfaces with various designable reversible polar topological structures can be tailored by complex straining flexible 2D materials, which provides excellent opportunities for next‐generation nanoelectronics and sensor devices. [ABSTRACT FROM AUTHOR]

It has been both theoretically predicted and experimentally demonstrated that strain can effectively modulate the electronic states of graphene sheets through the creation of a pseudomagnetic field (PMF). Pressurizing graphene sheets into bubble-like structures has been considered a viable approach for the strain engineering of PMFs. However, the bubbling technique currently faces limitations such as long manufacturing time, low durability, and challenges in precise control over the size and shape of the pressurized bubble. Here, we propose a rapid bubbling method based on an oxygen plasma chemical reaction to achieve rapid induction of out-of-plane deflections and in-plane strains in graphene sheets. We introduce a numerical scheme capable of accurately resolving the strain field and resulting PMFs within the pressurized graphene bubbles, even in cases where the bubble shape deviates from perfect spherical symmetry. The results provide not only insights into the strain engineering of PMFs in graphene but also a platform that may facilitate the exploration of the strain-mediated electronic behaviors of a variety of other 2D materials. [ABSTRACT FROM AUTHOR]

Designing economical and efficient nanocatalysts to enhance the efficiency and commercialization potential of direct ethanol fuel cells (DEFCs) is a challenging task. In the present study, we have crafted PdAg spatial nanodendrites (NDs) featuring distinct morphologies and precise compositional control, employing a streamlined one-step solvothermal approach. Modulating the molar quantity of the AgNO3 precursor can substantially modify the morphology and alloy composition of PdAg nanodendrites. The addition of Ag to the PdAg NDs resulted in lattice expansion, causing a shift in the d-band center of Pd. In addition, the porous nature of PdAg NDs provides numerous active sites for catalytic reactions, significantly enhancing the activity and stability of the ethanol oxidation reaction (EOR). It is important to note that the PdAg NDs exhibit "volcano" characteristics. Among these, the Pd9Ag1 NDs demonstrate excellent electrocatalytic activity and outstanding stability. It has been found to have an electrocatalytic activity of 2450 mA mgpd–1 for ethanol oxidation. This study offers a solution for the preparation of catalysts for fuel cells and motivates the creation of innovative structures to improve electrocatalytic activities. [ABSTRACT FROM AUTHOR]

The synthesis of cone‐shaped Pt nanoparticles featuring compressively‐strained {111} facets by depositing Pt atoms on the vertices of Pd icosahedral nanocrystals, followed by selective removal of the Pd template via wet etching, is reported. By controlling the lateral dimensions down to ca. 3 nm, together with a thickness of ca. 2 nm, the Pt cones show greatly enhanced specific and mass activities toward oxygen reduction, with values being 2.8 and 6.4 times those of commercial Pt/C, respectively. Both the strain field and the observed activity trend are rationalized using density functional theory calculations. With the formation of ultrathin linkers among the Pt cones derived from the same Pd icosahedral seed, the interconnected Pt cones acquire stronger interactions with the carbon support, preventing them from detachment and aggregation during the catalytic reaction. Even after 20 000 cycles of accelerated durability test, the Pt cones still show a mass activity 5.3 times higher than the initial value of the Pt/C. [ABSTRACT FROM AUTHOR]

Norbornadiene/Quadricyclane (NBD/QC) is a prototypical bridged bicyclic diene (BBD)‐based photoswitch that has been well‐studied for molecular solar thermal energy storage (MOST). Inspired by the recent synthetically accessed BBDs, herein several photoswitches are rationally designed with modulated ring strain energies (RSE) in photoisomers to incorporate high energy storage density (ESD) and storage time in a single couple. The storage energy ( ΔGstr ${{{\rm \Delta }{\rm G}}^{str}}$ ) calculated at DLPNO‐CCSD(T)/Def2TZVP level is correlated with difference in RSE of two isomers (ΔRSE) whereas thermal back reaction (TBR) barrier calculated at (8,8)‐CASPT2/6‐311++G** shows correlation with RSE in metastable photoproduct. On the basis of these structure‐property‐RSE relationships, we recognized that two photoisomers need not to be highly strained. Instead, the RSE in the photoproduct and diene should be minimized while maintaining a large enthalpy difference between them to increase ESD and extend energy storage times in a single photoswitch. TBR barrier is governed by RSE in photoproduct and increasing strain in photoproduct may improve the ΔGstr ${{{\rm \Delta }{\rm G}}^{str}}$ but at the cost of the TBR barrier. Herein, the structural skeletons are explored that holds promise to remarkably improve thermochemical properties relative to the unsubstituted BBD‐based photoswitches reported so far. The BBD molecules with short saturated bridge length but elongated unsaturated bridges could bestow desirable thermochemical parameters and can be regarded as excellent candidates for MOST application. The work lays a theoretical foundation that guides to improve thermochemical properties via strain engineering of BBD‐based photoswitches and opens a new avenue for designing principles and future experimental investigations of MOST systems. [ABSTRACT FROM AUTHOR]

Interlayer incommensurateness slippage is an excellent pathway to realize superlubricity of van der Waals materials; however, it is instable and heavily depends on twisted angle and super‐smooth substrate which pose great challenges for the practical application of superlubricity. Here, macroscale superlubricity (0.001) is reported on countless nanoscale graphene moiré structure (GMS)‐assembled surface via counterface hydrogen (H) modulation. The GMS‐assembled surface is formed on grinding balls via sphere‐triggered strain engineering. By the H modulation of counterface diamond‐like carbon (25 at.% H), the wear of GMS‐assembled surface is significantly reduced and a steadily superlubric sliding interface between them is achieved, based on assembly face charge depletion and H‐induced assembly edge weakening. Furthermore, the superlubricity between GMS‐assembled and DLC25 surfaces holds true in wide ranges of normal load (7–11 N), sliding velocity (0.5–27 cm −1s), contact area (0.4×104–3.7×104 µm2), and contact pressure (0.19–1.82 GPa). Atomistic simulations confirm the preferential formation of GMS on a sphere, and demonstrate the superlubricity on GMS‐assembled surface via counterface H modulation. The results provide an efficient tribo‐pairing strategy to achieve robust superlubricity, which is of significance for the engineering application of superlubricity. [ABSTRACT FROM AUTHOR]

Graphene is used as a growth template for van der Waals epitaxy of organic semiconductor (OSC) thin films. During the synthesis and transfer of chemical‐vapor‐deposited graphene on a target substrate, local inhomogeneities in the graphene—in particular, a nonuniform strain field in the graphene template—can easily form, causing poor morphology and crystallinity of the OSC thin films. Moreover, a strain field in graphene introduces a pseudo‐electric field in the graphene. Here, the study investigates how the strain and strain‐induced pseudo‐electric field of a graphene template affect the self‐assembly of π‐conjugated organic molecules on it. Periodically strained graphene templates are fabricated by transferring graphene onto an array of nanospheres and then analyzed the growth and nucleation behavior of C60 thin films on the strained graphene templates. Both experiments and a numerical simulation demonstrated that strained graphene reduced the desorption energy between the graphene and the C60 molecules and thereby suppressed both nucleation and growth of the C60. A mechanism is proposed in which the strain‐induced pseudo‐electric field in graphene modulates the binding energy of organic molecules on the graphene. [ABSTRACT FROM AUTHOR]

Formamidinium lead iodide (FAPbI3) has gained considerable interest as a promising photoactive layer for optoelectronic devices due to its broad spectrum of light absorption and increased thermal stability when compared to its conventional methylammonium counterpart (MAPbI3). Recent developments in substituting formamidinium (FA) with smaller Cs cations have further accelerated its growth in the photovoltaic (PV) community by enhancing phase stability and power conversion efficiency (PCE). However, only a few studies are reported on perovskite photodetectors (PPDs). Here, the influence of Cs incorporation is investigated on PD performance in the CsXFA1‐XPbI3 system (X = 0–0.25). Finding that the partial substitution of FA with Cs cations alleviates lattice strain by increasing crystallinity and inducing a well‐ordered surface morphology with vertical crystallographic orientation, which suppresses non‐radiative recombination mechanisms. Such improved physicochemical properties of the mixed‐cation perovskite light absorbers can improve the PD performance by reducing the dark and noise current to values as low as 3.3 × 10−9 A cm−2 and 6.1 × 1011 A Hz−1/2, thereby enabling PPDs with a faster photoresponse and greater sensitivity, which holds great promise for future optoelectronics applications. [ABSTRACT FROM AUTHOR]

Strain engineering has been proved to be an effective approach to modulate various physical properties in two-dimensional (2D) materials with flexible structures. In this work, based on first-principles calculations, the impact of in-plane biaxial tensile strain on lattice thermal conductivity of bilayer MoSe2, involving different stacking modes, has been systematically investigated by iteratively solving phonon Boltzmann transport equation. Simultaneously, potential regulations of interfacial anharmonic effect in phonon transport via in-plane strain can also be clarified through a comparative study between the monolayer and bilayer cases. Our results indicate that thermal transport in both the monolayer and bilayer MoSe2 is governed by low-frequency phonon branches, and the bilayer exhibits a notably reduced thermal transport capacity due to interlayer interaction existing in van der Waals homogeneous stacks. As the in-plane tensile strain is applied, a significant suppression in thermal transport capacity per layer can be further achieved in both the monolayer and bilayer cases, implying great potential for effective thermal management in 2D MoSe2 via strain engineering. Besides, the role of homogeneous interface in phonon transport of bilayer MoSe2 can also be regulated by the exerted in-plane tensile strain, which slows the decline in thermal conductivity with strain and leads to a larger thermal sheet conductance in the strained bilayer compared to the monolayer. [ABSTRACT FROM AUTHOR]

Clean and efficient hydrogen fuel as the future energy source for decarbonizing and establishing a sustainable carbon-neutral economy is highly attractive. Notable progress in hydrogen production through water splitting has been conducted to achieve zero carbon emissions, safety, and high product purity. Despite advancements, challenges like a significant large energy barrier with high cost associated with water splitting still exist. Efficient electrocatalysts have been designed to address the challenges of water splitting. Those catalysts aim to reduce energy barriers and costs associated with the process. Nevertheless, there are still challenges in promoting the industrialization of electrocatalytic water splitting. This review discusses the latest progress in water electrolysis, incorporating experimental evidence from in-situ spectroscopic surveys and computational analyses to provide a mechanistic understanding of hydrogen and oxygen evolution reactions. Various evaluation metrics and essential strategies are highlighted for designing and fabricating efficient electrocatalysts, including alloying, morphological engineering, interface construction, defect engineering, and strain engineering. This work aims to provide a knowledge-guided design in fundamental science, offering insights that could inspire technical engineering developments to build efficient electrocatalysts for water splitting. [Display omitted] • Essential parameters and evaluation metrics of electrode performances are discussed. • Crucial strategies for improving HER and OER works are summarized. • Alloying materials with a high-entropy configuration improves the long-term stability. • Porous materials with edges are essential for designing highly efficient electrodes. • Strain engineering on electrode surface modification shows a great promising strategy. [ABSTRACT FROM AUTHOR]

Strain engineering of the electrical and magnetic properties of perovskite manganites has attracted reasonable attention during the last decades. Here, we introduce a newly discovered Sr4Al2O7 as a buffer layer and achieve a successful tuning of the electrical transport properties of the La0.67Sr0.33MnO3 film grown by pulsed laser deposition via controlling the thickness and crystallinity of Sr4Al2O7. For a poorly crystallized Sr4Al2O7 buffer layer, the metallic and insulating state of La0.67Sr0.33MnO3 can be modulated by a small range of Sr4Al2O7 thickness, which is ∼2 nm for a film grown on LaAlO3 and ∼4 nm on SrTiO3 due to the different lattice mismatch. This Sr4Al2O7 buffer layer-controlled epitaxial growth and epitaxial strain provides a strategy to largely modulate the physics properties of perovskite manganites by a small change of the buffer layer. After dissolving Sr4Al2O7, the electrical transport properties of La0.67Sr0.33MnO3 can be preserved well in the freestanding films, showing the promising application potential for innovative electronic devices. [ABSTRACT FROM AUTHOR]

Photodetectors are widely used in various fields, such as industrial manufacturing and military defense. Researchers have recently sought a photodetector that combines high polarization sensitivity and a robust optical response. As an anisotropic semiconductor material, SnS holds potential for photodetection across the visible light spectrum. This study employs first-principles density functional theory (DFT) along with the non-equilibrium Green's function (NEGF) method to theoretically investigate the optoelectronic properties of the SnS monolayer in two device orientations: Armchair and Zigzag. It is found that the maximum photocurrent values between the two orientations are small at zero bias voltage, and stable photocurrent can be obtained by adding bias voltage. We examine the maximum photocurrent variation under linearly polarized light irradiation within a small bias voltage range (0.1 to 1.0 V), found for the maximum photoresponse of monolayer SnS to be large and stable at photon energy of 2.4 and 3.2 eV, and analyze the underlying mechanism of photoresponse, employing energy band and density of state diagrams. Additionally, we have calculated the extinction ratio of the SnS monolayer, confirming its strong polarization sensitivity. Finally, by subjecting the device to biaxial strain, we significantly speculate to enhance its asymmetry, leading to a substantial increase in photocurrent at zero bias. A compressive strain of - 6% notably increases the photocurrent. These findings offer valuable theoretical insights for the design of SnS monolayers as photodetectors. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) are playing irreplaceable roles in the construction of the future sustainable energy system. However, the insufficient performance of platinum (Pt)-based electrocatalysts for oxygen reduction reaction (ORR) hinders the overall efficiency of PEMFCs. Engineering the surface strain of catalysts is considered an effective way to tune their electronic structures and therefore optimize catalytic behavior. In this paper, insights into strain engineering for improving Pt-based catalysts toward ORR are elaborated in detail. First, recent advances in understanding the strain effects on ORR catalysts are comprehensively discussed. Then, strain engineering methodologies for adjusting Pt-based catalysts are comprehensively discussed. Finally, further information on the various challenges and potential prospects for strain modulation of Pt-based catalysts is provided. [ABSTRACT FROM AUTHOR]

Moiré superlattices, arising from the controlled twisting of van der Waals homostructures at specific angles, have emerged as a promising platform for quantum emission applications. Concurrently, the manipulation of strain provides a versatile strategy to finely adjust electronic band structures, enhance exciton luminescence efficiency, and establish a robust foundation for twodimensional quantum light sources. However, the intricate interplay between strain and moiré potential remains partially unexplored. Here, we introduce a meticulously designed fusion of strain engineering and the twisted 2L-WSe2/2L-WSe2 homobilayers, resulting in the precise localization of moiré excitons. Employing low-temperature photoluminescence spectroscopy, we unveil the emergence of highly localized moiré-enhanced emission, characterized by the presence of multiple distinct emission lines. Furthermore, our investigation demonstrates the effective regulation of moiré potential depths through strain engineering, with the potential depths of strained and unstrained regions differing by 91%. By combining both experimental and theoretical approaches, our study elucidates the complex relationship between strain and moiré potential, thereby opening avenues for generating strain-induced moiré exciton single-photon sources. [ABSTRACT FROM AUTHOR]

Layered trihalides exhibit distinctive band structures and physical properties due to the sixfold coordinated 3d or 4d transition metal site and partially occupied d orbitals, holding great potential in condensed matter physics and advanced electronic applications. Prior research focused on trihalides with highly symmetric honeycomb-like structures, such as CrI3 and α-RuCl3, while the role of crystal anisotropy in trihalides remains elusive. In particular, the trihalide MoCl3 manifests strong in-plane crystal anisotropy with the largest difference in Mo-Mo interatomic distances. Research on such material is imperative to address the lack of investigations on the effect of anisotropy on the properties of trihalides. Herein, we demonstrated the anisotropy of MoCl3 through polarized Raman spectroscopy and further tuned the phonon frequency via strain engineering. We showed the Raman intensity exhibits twofold symmetry under parallel configuration and fourfold symmetry under perpendicular configuration with changing the polarization angle of incident light. Furthermore, we found that the phonon frequencies of MoCl3 decrease gradually and linearly with applying uniaxial tensile strain along the axis of symmetry in the MoCl3 crystal, while those frequencies increase with uniaxial tensile strain applied perpendicularly. Our results shed light on the manipulation of anisotropic light-matter interactions via strain engineering, and lay a foundation for further exploration of the anisotropy of trihalides and the modulation of their electronic, optical, and magnetic properties. [ABSTRACT FROM AUTHOR]

Breaking linear scaling relations by strain engineering on Mo 3 C 2 MXene for effective electrochemical N 2 reduction to NH 3. [Display omitted] • Side-on and end-on N–N bonds are dominated by "P-P" and "E-E" weakening mechanisms. • Strain engineering breaks linear scaling relations of NRR intermediates. • Activity-selectivity trade-off is circumvented to have high catalytic performance. The development of N 2 reduction reaction (NRR) electrocatalysts with excellent activity and selectivity is of great significance, but adsorption-energy linear scaling relations between reaction intermediates severely hamper the realization of this aspiration. Here, we propose an elegant strain engineering strategy to break the linear relations in NRR to promote catalytic activity and selectivity. Our results show that the N–N bond lengths of adsorbed N 2 with side-on and end-on configurations exhibit opposite variations under strains, which is illuminated by establishing two different N 2 activation mechanisms of "P-P" (Pull-Pull) and "E-E" (Electron-Electron). Then, we highlight that strain engineering can break the linear scaling relations in NRR, selectively optimizing the adsorption of key NH 2 NH 2 ** and NH 2 * intermediates to realize a lower limiting potential (U L). Particularly, the catalytic activity-selectivity trade-off of NRR on MXene can be circumvented, resulting in a low U L of −0.25 V and high Faraday efficiency (FE), which is further elucidated to originate from the strain-modulated electronic structures. Last but not least, the catalytic sustainability of MXene under strain has been guaranteed. This work not only provides fundamental insights into the strain effect on catalysis but also pioneers a new avenue toward the rational design of superior NRR catalysts. [ABSTRACT FROM AUTHOR]

Micro-sized single-crystalline Ni-rich cathodes are emerging as prominent candidates owing to their larger compact density and higher safety compared with poly-crystalline counterparts, yet the uneven stress distribution and lattice oxygen loss result in the intragranular crack generation and planar gliding. Herein, taking LiNi0.83Co0.12Mn0.05O2 as an example, an optimal particle size of 3.7 µm is predicted by simulating the stress distributions at various states of charge and their relationship with fracture free-energy, and then, the fitted curves of particle size with calcination temperature and time are further built, which guides the successful synthesis of target-sized particles (w-NCM83) with highly ordered layered structure by a unique high-temperature short-duration pulse lithiation strategy. The W-NCM83 significantly reduces strain energy, Li/O loss, and cationic mixing, thereby inhibiting crack formation, planar gliding, and surface degradation. Accordingly, the m-NCM83 exhibits superior cycling stability with highly structural integrity and dual-doped m-NCM83 further shows excellent 88.1% capacity retention. [ABSTRACT FROM AUTHOR]

Abstract The engineering of ferroic orders, which involves the evolution of atomic structure and local ferroic configuration in the development of next‐generation electronic devices. Until now, diverse polarization structures and topological domains are obtained in ferroelectric thin films or heterostructures, and the polarization switching and subsequent domain nucleation are found to be more conducive to building energy‐efficient and multifunctional polarization structures. In this work, a continuous and periodic strain in a flexible freestanding BaTiO3 membrane to achieve a zigzag morphology is introduced. The polar head/tail boundaries and vortex/anti‐vortex domains are constructed by a compressive strain as low as ≈0.5%, which is extremely lower than that used in epitaxial rigid ferroelectrics. Overall, this study c efficient polarization structures, which is of both theoretical value and practical significance for the development of next‐generation flexible multifunctional devices.

Imposing and controlling strain in materials such as semiconductors or ferroelectrics is a promising way to obtain new or enhance existing properties. Although the field of strain engineering has seen a rapid expansion over the last two decades, straining semiconductor membranes over large areas remains a challenge. A generic way of tuning strain and hence band structure and electric or magnetic properties of any crystalline material can be obtained by compression of a composite structure involving poorly compressible elastomers. Mechanically similar to the principle of a hydraulic press, this work proposes a device and describes analytically a methodology to easily strain macroscopic membranes up to unprecedented values. Using in-situ X-ray diffraction and Raman spectroscopy, we tuned the biaxial strain in silicon membranes up to a value of 2.1 %, paving the way for new studies in the field of strain related physics, from semiconductors to perovskite oxide multiferroics.

Impact of strain of sub-3 nm gate-all-around (GAA) CMOS transistors on the circuit performance is evaluated using a neural compact model. The model was trained using 3D technology computer-aided design (TCAD) device simulation data of GAA field-effect transistors (FETs) subjected to both tensile and compressive strain in nMOS and pMOS devices. Strain was induced into the channel via lattice mismatch between the channel and source/drain epitaxial regions, as simulated by 3D TCAD process simulator. The transport models were calibrated against advanced Monte Carlo simulations to ensure accuracy. The resulting neural compact model demonstrated a close approximation to the original simulation results, achieving a minimal error of 1%. To assess the strain effect on circuit-level performance, SPICE simulations were conducted for a 5-stage ring oscillator and a 2-input NAND gate using the neural compact model. The propagation delay of the 5-stage ring oscillator improved from 3.60 ps to 2.85 ps when implementing strained GAA FETs. Also, strain enhanced the power-delay product of the 2-input NAND gate by 13.8% to 15.5%, depending on the input voltage sequence.

Clavulanic acid is a potent β-lactamase inhibitor produced by Streptomyces clavuligerus, widely used in combination with β-lactam antibiotics to combat antimicrobial resistance. This systematic review analyzes the most successful methodologies for clavulanic acid overproduction, focusing on the highest yields reported in bench-scale and bioreactor-scale fermentations. Studies have demonstrated that glycerol is the preferred carbon source for clavulanic acid production over other sources like starch and dextrins. The optimization of feeding strategies, especially in fed-batch operations, has improved glycerol utilization and extended the clavulanic acid production phase. Organic nitrogen sources, particularly soybean protein isolates and amino acid supplements such as L-arginine, L-threonine, and L-glutamate, have been proven effective at increasing CA yields both in batch and fed-batch cultures, especially when balanced with appropriate carbon sources. Strain engineering approaches, including mutagenesis and targeted genetic modifications, have allowed for the obtainment of overproducer S. clavuligerus strains. Specifically, engineering efforts that overexpress key regulatory genes such as ccaR and claR, or that disrupt competing pathways, redirect the metabolic flux towards CA biosynthesis, leading to high clavulanic acid titers. The fed-batch operation at the bioreactor scale emerges as the most feasible alternative for prolonged clavulanic acid production with both wild-type and mutant strains, allowing for the attainment of high titers during cultivations.

RuO2 is one of the benchmark electrocatalysts used as the anode material in proton exchange membrane water electrolyser. However, its long‐term stability is compromised due to the participation of lattice oxygen and metal dissolution during oxygen evolution reaction (OER). In this work, weakened covalency of Ru−O bond was tailored by introducing tensile strain to RuO6 octahedrons in a binary Ru−Sn oxide matrix, prohibiting the participation of lattice oxygen and the dissolution of Ru, thereby significantly improving the long‐term stability. Moreover, the tensile strain also optimized the adsorption energy of intermediates and boosted the OER activity. Remarkably, the RuSnOx electrocatalyst exhibited excellent OER activity in 0.1 M HClO4 and required merely 184 mV overpotential at a current density of 10 mA cm−2. Moreover, it delivered a current density of 10 mA cm−2 for at least 150 h with negligible potential increase. This work exemplifies an effective strategy for engineering Ru‐based catalysts with extraordinary performance toward water splitting. [ABSTRACT FROM AUTHOR]

Light‐emitting complex defects in silicon have been considered a potential platform for quantum technologies based on spin and photon degrees of freedom working at telecom wavelengths. Their integration in complex devices is still in its infancy and has been mostly focused on light extraction and guiding. Here the control of the electronic states of carbon‐related impurities (G‐centers) is addressed via strain engineering. By embedding them in patches of silicon on insulator and topping them with SiN, symmetry breaking along [001] and [110] directions is demonstrated, resulting in a controlled splitting of the zero phonon line (ZPL), as accounted for by the piezospectroscopic theoretical framework. The splitting can be as large as 18 meV, and it is finely tuned by selecting patch size or by moving in different positions on the patch. Some of the split, strained ZPLs are almost fully polarized, and their overall intensity is enhanced up to 7 times with respect to the flat areas, whereas their recombination dynamics is slightly affected accounting for the lack of Purcell effect. This technique can be extended to other impurities and Si‐based devices such as suspended bridges, photonic crystal microcavities, Mie resonators, and integrated photonic circuits. [ABSTRACT FROM AUTHOR]

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We synthesized an oxygen reduction reaction (ORR) model catalyst surface of Pt(111)/Nb-doped SnO2(101) (Nb:SnO2) coherent lattice stacking layers on a Pt(111) substrate and investigated the influence of the surface strain of the Pt(111) layer on ORR activity enhancement. The Nb:SnO2 lattice stacking layer was synthesized through arc-plasma deposition (APD) of SnNb on Pt(111) in a vacuum chamber (base pressure <10¹7 Pa), followed by thermal annealing at 823K for 120 min under 1 atm of dry air. The resulting Nb:SnO2/Pt(111) was then re-introduced into the chamber, and Pt was deposited by using an e-beam deposition method to form Pt/Nb:SnO2/Pt(111) ORR model catalyst surface. The cross-sectional, atomically resolved HAADF-STEM image of Pt/Nb:SnO2/Pt(111) clearly shows that the interfaces between the substrate Pt(111)/Nb:SnO2(101) and the Nb:SnO2(101)/surface Pt(111) match well and generate a single-crystal Pt(111)/Nb:SnO2(101)/Pt(111) ORR model catalyst surface. The synthesized catalyst surface showed ca. 3 times higher activity compared with clean Pt(111). It was estimated by in-plane-XRD that 0.6% of compressive strain worked on the surface Pt(111) layer, which was induced by a lattice mismatch between the surface Pt(111) and the underlaid Nb:SnO2(101). The results suggest that the ORR activity enhancement mechanism of the compressively strained surface Pt(111) lattice can be applied not only to Pt-based alloys of Pt and transition metal elements with smaller atomic radii but also to Pt on ceramic supports, such as SnO2. [ABSTRACT FROM AUTHOR]