Lattice Strain Research Articles

Mechanochemical synthesis of nitrogen-modified microscale zero-valent iron for efficient Cr(VI) removal: The role of lattice strain

Lattice engineering of Fe0 based on heteroatom doping holds great promise in water purification owing to their tunable geometric and electronic structure. However, there is limited understanding of how nitrogen atom in Fe0 lattice structure affects its local microenvironment and corresponding reactivity toward target contaminants. Herein, microscale zero-valent iron with interstitial N doping (N-mZVI) was successfully prepared by a facile mechanochemical method for heavy metal pollution control. N-mZVI exhibited excellent reactivity for Cr(VI) elimination, and both removal efficiency and conversion rate could reach 100 %, which was 8.06 and 2.73 times higher than that of pristine ball milled mZVI, respectively. Besides, the rate constant of various heavy metals sequestration (Cr(VI), Ni(II), Pb(II), Cu(II), and Cd(II)) over N-mZVI was 61.3 ∼ 115.6-fold faster than that of pristine ball milled mZVI. N-mZVI was also demonstrated to be pH-universal, long-term stability, and environmental applicability. Experimental results and theoretical calculations indicated that tensile strain induced by interstitial N doping expanded Fe0 lattice and weakened the lattice Fe-Fe interaction, thus significantly accelerating electron transport dynamics in Fe0 core. Meanwhile, iron nitride species on the surface of N-mZVI promoted electron transfer from iron shell layer to heavy metals. This work comprehensively investigates the structure–property relationships of lattice engineering-based N-mZVI, and provides a new insight into rational design of modified mZVI with high reactivity.

The Combination of Electronic Structure and Lattice Strain Engineering for Multi‐Powered Hydrazine‐Assisted Seawater Electrolysis System at High Current Densities

AbstractThe utilization of hydrazine in aiding water electrolysis presents a promising avenue for achieving highly efficient hydrogen production through energy conversion. Herein, bifunctional electrocatalyst of urchin‐like iron, nickle‐codoped cobalt phosphide supported on Ni foam (FeNi‐CoP/NF) is reported. Benefitting from the combined electronic structure and lattice strain engineering by Fe and Ni‐ codoping, the hydrazine‐assisted seawater electrolysis assembled with FeNi‐CoP/NF as both electrodes can achieve an industrial‐level current density of 1.5 A cm−2 at a record‐setting voltage of 163 mV at 70 °C and sustain stable operation for hundreds of hours in seawater environment. The existence of a potential coincidence region lends credibility to the feasibility of implementing self‐activated hydrazine‐assisted seawater electrolysis. Based on theoretical calculations, the separate and synergistic effects of electronic structure and lattice strain engineering are investigated and an integrated illustration of these two strategies on enhancing hydrogen evolution and hydrazine oxidation activity is provided. Moreover, an innovative multi‐powered hydrogen generation system featuring a direct hydrazine fuel cell, rechargeable Zn‐hydrazine battery, and hydrazine‐assisted seawater electrolysis is proposed, underscoring the unique advantages of hydrazine oxidation reaction and its prospective contribution to electrochemical energy conversion technologies powered by sustainable sources.

Lithium doping's effects on the microstructural, dielectric, energy storage, optical and electrical properties of BaTi0.89Sn0.11O3 ceramics

The present study discusses the synthesis of lithium-doped barium stannate titanate BaTi0.89Sn0.11O3 (BTS11) using sol–gel synthesis route and explores the influence of the lithium content on their structural, morphological, ferroelectric, optical, and electrical properties. The phase of the sol–gel prepared samples with different atomic composition BaLixTi0.89Sn0.11O3(BLxTS11), with x = 0 %, 2 %, 4 %, 6 %, 8 and 10 %, was investigated using X-ray diffraction (XRD) revealing the formation of pure perovskite exhibiting lattice strain. Structural characterization was additionally conducted using Raman spectroscopy to detect structural and the chemical environment modifications caused Li incorporation. The doping induced variation also in the morphology and grain size of BLxTS11 pellets studied using SEM micrographs, which revealed evident grain size changes inversely proportional to the BLxTS11 lattice strain. The samples were then inspected for their ferroelectric properties. The maximum dielectric constant of all samples was observed at a temperature of around 45–50 °C. In addition, correlations between the chemical, structural, and morphological properties of the BLxTS11 ceramics and their energy storage capabilities were established. According to the P-E hysteresis behavior, BL6TS11 ceramic (x = 6 %) ferroelectric demonstrated the highest energy-storage capabilities, with a recoverable energy-storage density of 225 mJ/cm3 and an energy-storage efficiency of 60 %. The optical and electrical properties of the material were also investigated revealing a decrease in the band gap values and a significant increase of resistivity by Li doping.

Investigating grain-resolved evolution of lattice strains during plasticity and creep using 3DXRD and crystal plasticity modelling

Microstructure-informed crystal plasticity finite element models have shown great promise in predicting plastic and creep deformation in polycrystalline materials. These models can provide substantial insight into the design, fabrication and lifetime assessment of critical metallic components during operation, for instance, in thermal power plants. However, to correctly incorporate damage prediction into models, the microstructural strain simulated at the grain level must be accurately predicted with suitable validation. For this reason, a 3D X-ray Diffraction (3DXRD) experiment was carried out on 316H stainless steel, a material commonly used in thermal power plants, to obtain the per-grain strain response during plastic and creep deformation at 550°C. Several hundred grains within a probed X-ray volume were tracked and measured whilst loading in-situ, obtaining per-grain centre-of-mass positions, crystallographic orientations, and average lattice strain over individual grains. These data were used to calibrate a crystal plasticity model to study the plastic and creep deformation using macroscopic stress-strain and stress-relaxation data. Subsequently, the model was used to predict the average elastic strain in different grains during the cyclic creep experiment, which was validated by 3DXRD datasets. The model results reveal that {100} or {311} grain families are strongly sensitive to microstructure, thereby a polycrystal model that describes specific orientation and neighbourhood characteristics is essential to predict the local response of these grain families. Whereas, self-consistent models are suitable for {110} and {111} grain families. This study shows that only with a suitable calibration of subsurface grain behaviour, crystal plasticity models reveal grain characteristic-dependent micromechanical behaviour.

Strain in Halide Perovskite Solar Cells: Origins, Impacts, and Regulation

Perovskite solar cells have made significant progress in the past decade, demonstrating promising potential for next‐generation solar technology. However, the strain‐induced intrinsic instability of mixed‐halide perovskites poses a significant obstacle to their widespread commercialization. Relaxation of the perovskite lattice strain is a crucial approach for enhancing photovoltaic performance and broadening their application potential. In this study, the authors conduct an analysis of strain progression in perovskite thin films, examining its impact on the physical properties of perovskites and the performance of perovskite solar cells. Furthermore, they explore its influence on device stability from the perspectives of phase transitions, chemical decomposition, and mechanical fragility. Additionally, they provide a summary of key advancements in strain‐relaxation strategies and offer design principles and synthetic approaches to address the issue of lattice strain in perovskites. This paper is intended to lay the groundwork for the theoretical development of effective strain‐relaxation methods, moving beyond sole reliance on empirical optimization.

Outstanding Room‐Temperature Thermoelectric Performance of n‐type Mg3Bi2‐Based Compounds Through Synergistically Combined Band Engineering Approaches

AbstractThermoelectric cooling materials based on Bi2Te3 have a long history of unsurpassed performance near room temperature. Recently, research into price‐competitive Mg3(Bi, Sb)2‐based materials are focused on replacing traditional cooling materials. Here, the thermoelectric properties of Mg3.2Bi1.998−xSbxTe0.002Cu0.005 (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) polycrystalline compounds are investigated. In all temperature regions, electrical resistivity and Seebeck coefficient are increased with Sb concentration. The electronic transport properties of Sb‐alloyed compounds are maximized by synergistically combined band engineering approaches such as band structure change caused by lattice strain, increased electronic density of states, and chemical potential shift, leading to exceptionally high‐power factor values of over 3.0 mW m−1 K−2 at room temperature. Furthermore, with increasing Sb content, thermal conductivity values are systematically reduced due to the promotion of alloy scattering of phonons and suppression of the bipolar contribution. Consequently, these multiple approaches significantly enhance thermoelectric performance, resulting in an enhancement of thermoelectric figure‐of‐merit zT above 1.1 at 348–423 K. Additionally, a zTavg of 1.1 is recorded at 300–450 K, making it an unrivaled value among the reported n‐type Mg3Bi2‐based thermoelectric materials. Overall, this work demonstrates that Mg3Bi2‐based materials are more promising for thermoelectric cooling applications compared to Bi2Te3‐based materials.

Effect of deposition regime transition on the properties of Al:ZnO transparent conducting oxide layer by radio frequency magnetron sputtering system

High-quality zinc oxide thin films doped with aluminium adatoms have effectively been fabricated on pristine soda-lime silica glass substrates via radio frequency magnetron sputtering system. The deposition temperature was varied to explore the impact of deposition regime transition of as-deposited Al:ZnO thin films on their performance as transparent conducting oxide layers. In particular, the depositions were conducted at room temperature, 100 °C, 200 °C, and 300 °C, allowing for a comprehensive assessment of the resulting films. The Raman spectra depicted the modulation of Raman bands in correlation with the deposition regime transition, illustrating the impact of thermal induction on various properties of the as-deposited aluminium-doped zinc oxide thin films. Atomic force microscopy reveals the transformation from nearly spherical to elongated shape structure was obtained as the deposition process shifted from kinetic limited to thermodynamic limited regimes. The phase analysis and grazing incident of x-ray diffractometer disclose a single crystal orientation has been achieved at thermodynamic limited regime. However, two different crystal planes were predominant comparing between the surface and structural of as-deposited aluminium-doped zinc oxide thin films. It is also evident that a highly transparent with low lattice strain and better carrier concentrations of as-deposited aluminium-doped zinc oxide thin films were realized at thermodynamic limited regimes.

A novel plasma-facing NdB6 particulate reinforced W1Ni matrix composite: Powder metallurgical fabrication, microstructural and mechanical characterization

Tungsten (W) is one of best candidate metal for plasma-facing materials (PFM), especially due to its high melting temperature and neutron absorption capability. However, converting W into bulk PFM is hard because of its high melting point. This problem can be solved by adding metallic sintering aids with low melting points. In this study, W matrix with 1 wt% Ni aid was reinforced by adding NdB6 particles (1, 5, and 10 wt%). It can be introduced as a novel potential PFM, thanks to its low volatility and high neutron absorbability. The ceramic and composite powders produced via mechanochemical synthesis and mechanical alloying were examined in terms of composition, particle size, crystallite size, and lattice strain. Samples sintered via pressureless sintering (PS) and spark plasma sintering (SPS) were microstructurally analyzed by using an X-ray diffractometer (XRD), a scanning electron microscope (SEM) attached with an energy dispersive spectroscope (EDS), and mechanically analyzed in terms of microhardness and wear behavior. Based on the results, W2B and WB phases emerged in the SPS'ed W1Ni-5NdB6 and PS'ed./SPS'ed W1Ni-10NdB6 composites. SPS'ed W1Ni-10NdB6 composite had the highest hardness value and the lowest specific wear rate. The SPS'ed W1Ni-5NdB6 composite showed fewer surface damages and higher irradiation resistance as compared with other samples after exposure of He+ irradiation.

Surface Functionalization of Novel Work‐Hardening Multi‐Principal‐Element Alloys by Ultrasonic Assisted Milling

The development of multi‐principal‐element alloys (MPEAs) with unique characteristics such as high work hardening capacity similar to well‐known alloy systems like Hadfield steel X120Mn12 (ASTM A128) is a promising approach. Hence, by exploiting the core effects of MPEAs, the application range of conventional alloy systems can be extended. In the present study, work‐hardening MPEAs based on the equimolar composition CoFeNi are developed. Mn and C are alloyed in the same ratio as for X120Mn12. The production route consists of cast manufacturing by an electric arc furnace and surface functionalization via mechanical finishing using ultrasonic‐assisted milling (USAM) to initiate work hardening. The microstructure evolution, the hardness as well as the resulting oscillating wear resistance are detected. A pronounced lattice strain and grain refinement due to the plastic deformation during the USAM is recorded for the MPEA CoFeNi‐Mn12C1.2. Consequently, hardness increases by ≈380 HV0.025 in combination with a higher oscillating wear resistance compared to the X120Mn12. This shows the promising approach for developing work‐hardening alloys based on novel alloy concepts such as MPEAs.

Examining the distribution of Middle Paleolithic Nubian cores relative to chert quality in southern (Nejd, Dhofar) and south‐central (Duqm, Al Wusta) Oman

AbstractLithic raw material properties are often invoked to explain the presence, absence, form, or ontogeny of Paleolithic stone tools. Here, we explore whether the frequency of the Middle Paleolithic Nubian core form and core‐reduction systems co‐varies with toolstone quality in two neighboring regions in Oman: the southern region of Nejd, Dhofar, and the south‐central region of Duqm, Al Wusta. Specifically, we predicted that if raw material differences were influencing the distribution of Nubian cores, the chert would be of higher quality in the southern region, where Nubian cores were frequent, and of lower quality in the south‐central region, where they were scarce. We tested this prediction by collecting 124 chert samples from 22 outcrops and then quantitatively assessed two geochemical variables that are widely thought to influence knapping: impurity amount and silica content. We also examined the mineralogical composition, and the crystallite size and lattice strain for quartz (crystalline α‐SiO2) of representative chert samples. Our results suggest that the cherts in the two regions are similar, which is not consistent with the hypothesis that lithic raw material quality contributed to Nubian core spatial distribution in Oman. We discuss potential alternative hypotheses to explain Nubian core geographic patterning, and provisionally suggest that the scarcity of Nubian cores in south‐central Oman may be due to a concomitant scarcity of toolmakers, given a lack of water availability.

Full Picture of Lattice Deformation in a Ge1 - xSnx Micro-Disk by 5D X-ray Diffraction Microscopy.

Lattice strain in crystals can be exploited to effectively tune their physical properties. In microscopic structures, experimental access to the full strain tensor with spatial resolution at the (sub-)micrometer scale is at the same time very interesting and challenging. In this work, how scanning X-ray diffraction microscopy, an emerging model-free method based on synchrotron radiation, can shed light on the complex, anisotropic deformation landscape within three dimensional (3D) microstructures is shown. This technique allows the reconstruction of all lattice parameters within any type of crystal with submicron spatial resolution and requires no sample preparation. Consequently, the local state of deformation can be fully quantified. Exploiting this capability, all components of the strain tensor in a suspended, strained Ge1 - xSnx /Ge microdisk are mapped. Subtle elastic deformations are unambiguously correlated with structural defects, 3D microstructure geometry, and chemical variations, as verified by comparison with complementary electron microscopy and finite element simulations. The methodology described here is applicable to a wide range of fields, from bioengineering to metallurgy and semiconductor research.

Size dependent dual functionality of CeO2 quantum dots: A correlation among parameters for hydrogen gas sensor and pollutant remediation

The metal oxide-based nanostructures of variable size and shape are found effective in optimizing the gas sensing ability and pollutant degradation. The size induced lattice strain and large band gap in 3nm CeO2 quantum dots evolved the ability towards hydrogen gas sensing and dye degradation compared to nanopebbles and nanoparticles of sizes 15 ± 3, and 30 ± 12 nm. The smaller CeO2 quantum dots than Debye length was found underlying reason for nearly four times sensor response and selectivity towards reducing hydrogen gases than the oxidizing gases at 1–10 ppm level. The lattice strain calculated by Rietveld refinement and W–H analysis was found in-line with the size of CeO2 nanostructures. The enhancement in lattice strain and optical band gap (2.66, 2.78, and 2.89 eV) with decrease in size are found critical for determining the overall efficiency of CeO2 nanostructures for photocatalytic activity, attributed to the strong quantum confinement effect. The higher catalytic activity of 98 % was achieved CeO2 quantum dots in comparison to the 95 % and 94 % obtained for CeO2 nanopebbles and nanoparticles. The impact of change in degradation efficacy and gas sensing ability of different CeO2 nanomaterials is discussed in detail. This work offers a novel and simplistic method to produce CeO2 quantum dots as an efficient sensor for selective detection of H2 gas and photocatalyst. The correlation between size, Debye length, band gap, and lattice strain gives an insight for understanding the underlying detection mechanism for selective detection of reducing gas molecules and efficient pollutant remediation.

Investigation of the role of sintering temperature on microstructure, ac conductivity, and dielectric constant of single phase NiSnO3 nanopowder

This study investigates the effect of sintering temperature on the structural and electrical properties of co-precipitated nickel stannate (NiSnO3) nanopowder. Sintering temperatures, determined using Thermo Gravimetric Analysis (TGA), reveal a pure hexagonal perovskite structure through X-ray diffraction (XRD) analysis. Crystallite size increased from 10.56 nm to 26.04 nm and lattice strain decreased from 23.05×10−3 to 2.35×10−3 with higher sintering temperatures, analyzed via the Scherrer formula. d-spacing values from SAED patterns align with XRD results, and TEM analysis shows particle size growth from ∼11.43 nm to ∼28.16 nm as sintering temperature rises from 600°C to 900°C. Elemental composition has been confirmed through EDX, and elemental mapping analysis. Impedance spectroscopy via Cole-Cole plots indicated non-Debye-type or multiple relaxations with depressed semicircles due to grain and grain boundary effects. The sample sintered at 900°C exhibits the highest conductivity (8.35×10−5 Ω−1cm−1) with lowest activation energy of 0.31 eV and maximum dielectric constant values, with a minimum relaxation time of 0.00029 sec. Also the frequency variation of Z′′ and M′′ confirm the presence of non-Debye type relaxation. Scaling behavior of the imaginary part of complex impedance and conductivity spectra confirms temperature-independent conduction and relaxation mechanisms. These materials are used in energy storage applications.

Lattice-Strain Engineering in Ni-Ru Heterostructures for Efficient Acetylene Hydrochlorination toward Vinyl Chloride.

Ru-based catalysts have emerged as promising alternatives to HgCl2 in vinyl chloride monomer (VCM) production by acetylene hydrochlorination. However, poor C2H2 activation and the generation of key intermediates (*CH2═CH) have posed grand challenges for enhanced catalytic performances. Herein, we synthesized a Ni-intercalated Ru heterostructure using a lattice-strain engineering strategy, resulting in the desired electronic and chemical environments. The collaboration of Ni splits the adsorption centers of C2H2 and HCl by weakening the strong steric hindrance, and it also promotes the activation of the linear C≡C configurations. The well-controlled lattice strain enables strong d-d hybridization interactions between Ni and Ru, resulting in an upshift of the d-band center from -3.72 eV (for Ru/C) to -3.49 eV and electronic delocalization. This optimized local Ni-Ru/C structure thus enhances *H adsorption while weakening the energy barrier for generating *CH2═CH intermediates. Furthermore, the energy barrier for VCM formation was simultaneously reduced. Accordingly, the Ni-Ru/C heterostructures achieve improved performance in pilot-scale trials, with a conversion of >99.2% and stability for over 500 h. These performances significantly surpass most reported Ru-based moieties and the traditional Hg catalysts, offering a promising avenue for C2H2 activation in industrial applications.

Microstructural evolution of CrCuFeNiZn nanocrystalline high entropy alloy prepared by mechanical alloying

High Entropy Alloys (HEAs) have become the most researched structural materials in the scientific community during the last decade due to their attributes like excellent strength and wear resistance. In this research, CrCuFeNiZn HEA was prepared using mechanical alloying technique. Further, X-ray diffraction (XRD) and Scanning electron microscope (SEM) analysis of prepared HEA were carried out at various milling time intervals (10 min, 5 h, 10 h, 15 h, 20 h, and 25 h) to determine solid solution formation. Results manifest that CrCuFeNiZn HEA exhibited BCC + FCC (dual phase) structure after 25 h of milling. Moreover, the crystallite size as measured from the XRD analysis for the 25 h milled powder was found to be 32.8 nm and lattice strain at the end of milling is calculated to be 0.428%. SEM-EDS analysis further confirms the homogeneous distribution of the constituting elements in the as-fabricated alloy aggregate.

Ferroelastic strain control of multiple nonvolatile resistance tuning in Cr:In2O3/PMN-PT(111) multiferroic heterostructures

Strain can significantly affect the electronic structure and functional properties of dilute magnetic semiconductors. As a wide bandgap transparent semiconductor, doped In2O3 has also received extensive attention for the modulation of physical properties by lattice strain due to its excellent functional properties. Here, we epitaxially grew the Cr:In2O3 thin film on the (111)-oriented 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 (PMN–PT) ferroelectric single-crystal substrate. By applying an electric field to PMN–PT, multiple reversible and nonvolatile resistance states can be achieved at room temperature. Utilizing in situ XRD, different strain states corresponding to different resistance states induced by the ferroelastic domain switching of the PMN–PT were characterized. Based on first-principles calculations, the influence of lattice strain on the resistivity of the Cr:In2O3 was discussed. These results offer a route for the design of multiple-valued nonvolatile memory devices and multiple functional magneto-electric devices based on dilute magnetic semiconductors.

Spatially-resolved in-situ/operando structural study of screen-printed BaTiO3/P(VDF-TrFE) flexible piezoelectric device

The incorporation of lead-free BaTiO3 particles into P(VDF-TrFE) provides a versatile way for tuning dielectric and piezoelectric properties. Screen-printing enables the easy production of flexible capacitors. To prevent particle aggregation, the BaTiO3 particles are functionalized with a surfactant. Initially, 60 % vol. BaTiO3 particles are deposited in the second layer out of three layers. After annealing and cooling, the particle distribution is successfully homogeneous in the whole film. After poling at 80 °C, the relative permittivity and the piezoelectric coefficient d33 significantly increase up to 159 and 8 pC/N respectively. In situ/operando spatially-resolved X-ray techniques allow exploring the structural evolution of the composite device during annealing and during an applied electric field. The application of an electric field leads to the quasi-disappearance of the P(VDF-TrFE) ferroelectric state. As a matter of fact, the interactions between the P(VDF-TrFE) and the surfactant may limit the rotation of P(VDF-TrFE) chains near the particles. Hence, paraelectric polymers could be chosen on a mechanical or economic basis for the matrix in piezoelectric composite devices. Regarding BaTiO3, the lattice strain evolves from an extrinsic strain at RT to an intrinsic strain after annealing and cooling. At the cooled state, the tetragonality c/a is higher than 1.01, leading to improved piezoelectric properties. The increase of the average domain size leads to the increase of the composite permittivity. Finally this knowledge facilitates the development of tailored flexible piezoelectric composite devices.

Ultrahigh-nickel layered cathode with cycling stability for sustainable lithium-ion batteries

Nickel-rich layered transition metal oxides are leading cathode candidates for lithium-ion batteries due to their increased capacity, low cost and enhanced environmental sustainability compared to cobalt formulations. However, the nickel enrichment comes with larger volume change during cycling as well as reduced oxygen stability, which can both incur performance degradation. Here we show an ultrahigh-nickel cathode, LiNi0.94Co0.05Te0.01O2, that addresses all of these critical issues by introducing high valent tellurium cations (Te6+). The as-prepared material exhibits an initial capacity of up to 239 milliampere-hours (mAh) per gram and an impressive capacity retention of 94.5% after 200 cycles. The resulting Ah-level lithium metal battery with silicon-carbon anode achieves an extraordinary monomer energy density of 404 watt-hours (Wh) per kilogram with retention of 91.2% after 300 cycles. Advanced characterizations and theoretical calculations show that the introduction of tellurium serves to engineer the particle morphology for a microstructure to better accommodate the lattice strain and enable an intralayer Te–Ni–Ni–Te ordered superstructure, which effectively tunes the ligand energy-level structure and suppresses lattice oxygen loss. This work not only advances the energy density of nickel-based lithium-ion batteries into the realm of 400 Wh kg−1 but suggests new opportunities in structure design for cathode materials without trade-off between performance and sustainability.

Employing lattice compression spin polarization electric field for boosting degradation of mixed antibiotics in wastewater

Localized polarization electric field is a key factor affecting photocatalytic activity. In this study, the localized polarization electric field of lattice strain was introduced into the electronic structure of Bi2WO6 by using the high and low valence state doping method. The impurity energy level induced by lattice strain further affects the gap energy level. As an intermediate state for electron transfer, the gap level further promotes the dynamics of photo generated charges, reducing the band gap by 0.4 eV and improving the photoelectric performance by 60 %. Various tests and theoretical calculations have confirmed that the internal electric field of local polarization significantly improves the generation and transfer rate of photo-generated charges, thereby boosting catalytic activity. The removal ratios of ciprofloxacin (CIP) and tetracycline (TC) in the mixed wastewater reach 91.5 % and 97.1 % in 90 min, respectively. Cyclic tests have shown that the electronic structure control exhibits excellent stability with removal ratios of CIP and TC of 83.9 % and 85.7 %, respectively. Finally, the 8C of CIP and the 11C and 19O of TC are most susceptible to the attack of free radicals generated by lattice compression spin polarization electric fields based on the theoretical calculations of the Fukui function and the analysis of intermediates. This work provides new insights into the design of catalysts for efficient photo generated charge dynamics with lattice strain.

Intercalation-Induced Irreversible Lattice Distortion in Layered Double Hydroxides.

Inducing strain in the lattice effectively enhances the intrinsic activity of electrocatalysts by shifting the metal's d-band center and tuning the binding energy of reaction intermediates. NiFe-layered double hydroxides (NiFe LDHs) are promising electrocatalysts for the oxygen evolution reaction (OER) due to their cost-effectiveness and high catalytic activity. The distorted β-NiOOH phase produced by the Jahn-Teller effect under the oxidation polarization is known to exhibit superior catalytic activity, but it eventually transforms to the undistorted γ-NiOOH phase during the OER process. Such a reversible lattice distortion limits the OER activity. In this study, we propose a facile boron tungstate (BWO) anion intercalation method to induce irreversible lattice distortion in NiFe LDHs, leading to significantly enhanced OER activity. Strong interactions with BWO anions induce significant stress on the LDH's metal-hydroxide slab, leading to an expansion of metal-oxygen bonds and subsequent lattice distortion. In situ Raman spectroscopy revealed that lattice-distorted NiFe LDHs (D-NiFe LDHs) stabilize the β-NiOOH phase under the OER conditions. Consequently, D-NiFe LDHs exhibited low OER overpotentials (209 and 276 mV for 10 and 500 mA cm-2, respectively), along with a modest Tafel slope (33.4 mV dec-1). Moreover, D-NiFe LDHs demonstrated excellent stability at 500 mA cm-2 for 50 h, indicating that the lattice distortion of the LDHs is irreversible. The intercalation-induced lattice strain reported in this study can provide a general strategy to enhance the activity of electrocatalysts.