Induced Lattice Distortion Research Articles

High ferroelectric polarization and bandgap modulation in Sol-gel-Synthesis BiFe1–2xAxCoxO3 (A=Mn2+, Ti4+) polycrystalline films

Co-doping of Fe sites in BiFeO3 polycrystalline films effectively suppresses leakage current. Polycrystalline BiFe1–2xMnxCoxO3 and BiFe1–2xTixCoxO3 (x = 0, 0.01, 0.02, 0.03) films were prepared using the sol-gel spin-coating method. A systematic investigation was conducted to determine the impact of (Mn2+/Ti4+, Co2+) co-doping on the structural, leakage current, ferroelectric, dielectric, and optical properties of BiFeO3 films. Results reveal that BiFe1–2xAxCoxO3 (A=Mn2+, Ti4+) films maintain a stable tripartite structure, with (Mn2+/Ti4+, Co2+) co-doping inducing lattice distortion. The leakage current density of BiFe0.98Mn0.01Co0.01O3 (3.45×10−7 A/cm2) and BiFe0.96Ti0.02Co0.02O3 (2.05×10−6 A/cm2) is reduced by 2–3 orders of magnitude relative to pure BiFeO3. Additionally, these films exhibit high remanent polarization values of 188.4 μC/cm2 and 186.8 μC/cm2, respectively. Optical band gaps decrease with (Mn, Co) co-doping and increase with (Ti, Co) co-doping. The magnetic properties are enhanced with increased (Mn, Co) doping but are reduced as (Ti, Co) doping increases. This study provides enhanced understanding of Fe-site co-doping's role in reducing leakage current and improving ferroelectricity in BiFeO3 films, offering valuable insights for photovoltaic applications involving BiFeO3 thin films.

Oxides improve the strength of Zn-0.5Mn-0.5Mg alloys proceeded by laser powder bed fusion

Laser powder bed fusion has recently been adopted to fabricate biodegradable Zn alloys. But the mechanical properties need to be further improved to meet the requirements for natural bone implants. In this study, a ternary Zn-0.5Mn-0.5Mg biodegradable alloy is prepared by laser powder bed fusion technique. The as-printed sample shows a large compressive yield strength of 267 MPa and considerable ductility that the sample maintains its integrity after 50 % compression. The improved strength is mainly attributed to the formation of brittle Zn oxides, Mn oxides and Mg oxides which induce lattice distortion. These oxides fragment easily during the compression and reduce the stress concentration, resulting in significant ductility. More importantly, the as-printed sample shows a moderate degradation rate of 0.08 mm/year after immersing in the simulated body fluid solution for 7 days. In addition, the sample has MC3T3-E1 cell viabilities higher than 75 %, showing no-toxicity characteristic. This study demonstrates that laser powder bed fusion Zn-Mn-Mg alloy is a promising candidate for biodegradable materials and proposes a novel route to tailor the mechanical properties of additive-manufactured Zn alloys by oxides compositing.

Mechanical-energy-driven HCHO purification with lattice distortion engineering and surface grafting

Formaldehyde (HCHO) is a typical indoor air pollutant with high toxicity and wide distribution. It is of great significance to use clean energy for efficient catalytic oxidation of HCHO. In this work, Fe-doped bismuth titanate (Bi4Ti3O12) nanosheets with polyethyleneimine (PEI) grafting were prepared, exhibiting a remarkable complete elimination of HCHO under ultrasonic vibration. Piezocatalytic mechanism analysis revealed that Fe3+ doping induced lattice distortion and accelerated the transfer of electrons through valence change. Additionally, the abundant amino groups in PEI efficiently gathered formaldehyde molecules on the surface of the catalysts for next catalytic reaction as well as accelerate the separation of carriers by trapping holes as strong electron donors. It showed an effective strategy for degrading organic pollutants in the air with adsorption-enhanced piezocatalysts driven by mechanical energy.

Lithium modulated spinel high entropy oxide anode of LIBs through microwave solvothermal method

Spinel structured high entropy oxides (HEO) with three-dimensional Li+ transport channel and two different Wyckoff sites show high theoretical capacities due to multiple hypervalent ions and abundant oxygen vacancies. However, the intrinsic poor electrical conductivity of oxides and the lack of low-energy-consumption synthesis methods remain problems. Herein, Li+ with low-electronegativity is introduced into (FeCoNiCrMn)3O4 through high-efficiency microwave-assisted solvothermal method. The nano-scale high entropy oxide particles with homogeneous distribution of elements are successfully obtained in a short time. The addition of Li+ in HEO not only increases the valence states of transition metal cations to increase the number of electron transfers, but also induces more oxygen vacancies, which facilitates Li ion storage and increases ionic conductivity. The Li induced lattice distortion together with the entropy stabilization mechanism alleviate the lattice stress, featuring the anode superior electrochemical stability. The anode HEO-15 with the optimal Li content shows the specific capacity of 452.8 mAh g-1 at a current density of 500 mA g-1 after 300 cycles for LIBs, much higher than that of HEO-0 (248.9 mAh g-1). This research provides an effective method to improve the lithium storage performance of HEO.

Optimized strain property in Sm3+ doped 0.67BiFeO3-0.33BaTiO3 ceramics by electric field induced lattice distortion and domain wall motion

BiFeO3-BaTiO3 based ceramics with good piezoelectric properties and high Curie temperature are potential candidates for high temperature piezoelectric actuators. In this study, a high strain value of about 0.376 % and the low strain hysteresis of 13.3 % achieved in 0.67Bi1-xSmxFeO3-0.33BaTiO3 (0.1 ≤ x ≤ 2.0) ceramics. The contribution from the E-induced nanodomains and/or PNRs wall motion by fine-tuning Sm3+ contributes the increased strain; The contribution from the converse piezoelectric effect and the electrostrictive effect enhanced with the increase of x, due to the enlarged lattice shrinkage by replacing Sm3+ with small ionic radius and subsequent lattice distortion under high electric field. The strategy to simultaneously enhance the E-induced lattice distortion and nanodomains and/or PNRs wall motion of strain and balance their fractions to reduce the strain hysteresis may provide new insights to meet the practical applications of high-precision displacement actuators.

Rare earth induced lattice distortion of Bi2WO6 to effectively improve photocatalytic performance: Experimental and DFT calculations

The excellent visible light photocatalytic activity of bismuth-based photocatalysts has attracted the interest of many scholars at home and abroad. In this paper, rare earth (Sm, La, Ce, Eu) doped Bi2WO6 photocatalysts were prepared by a one-step hydrothermal method using bismuth nitrate and sodium tungstate as precursors. The microstructures and spectroscopic performances of prepared materials were investigated utilizing characterization methods, such as XRD, XPS, UV–vis, TEM, and N2 adsorption-desorption, etc., and the effluent removal performances were studied by using rhodamine B as a simulated degradation dye and the photodegradation mechanism was investigated in combination with DFT calculations. XRD indicates that the rare earth doping leads to the lattice distortion of the (131) crystal surface of Bi2WO6, and the relative amount of distortion is directly proportional to the photocatalytic activity; UV–vis spectra show that the absorption edge of Bi2WO6 is obviously red-shifted with the rare earth doping, and N2 adsorption-desorption curve show that the doped rare earths make the specific surface area of the sample effectively increased. Moreover, XPS spectrum suggests that the doped rare earth Ce and Eu often exist in the form of metastable oxidation states, and the transformation between Ce3+/Ce4+ and Eu2+/Eu3+ oxidation states is easy to form impurity energy levels between Bi2WO6, which make the energy level significantly enriched to broaden the absorption range and reduce band gap width of the material. DFT calculations further indicate that the rare earths successfully replace Bi sites. One of the main reasons for the improvement of photocatalytic activity is that rare earth doping is easier to replace Bi sites, leading to increased relative aberration; another one is that the arrangement of EVB and ECB in the photocatalytic mechanism is type-II, which contributes to red-shift of absorption edge and effective separation of electron-hole pairs in the photocatalytic process, thus improving the photocatalytic activity.

Investigation of structural and optoelectronic integrity of Sm3+ doped CaWO4 for LED applications

In this study we illustrate the structural, electronic and optical integrity of Ca1-xSm(2/3)xWO4 (x = 0.00, 0.02, 0.04, 0.06 and 0.08) crystals for optoelectronic applications via experimental and first principles approach. According to our experimental outcomes, CaWO4 crystallizes in scheelite type tetragonal structure devoid of impurity which depends on the A-site cationic radius and dopant-host compatibility. As a result, the dopant induced lattice distortion occur due to symmetric and asymmetric stretching of (Ca, Sm)—O and W–O bonds within [CaO8] and [WO4] cluster. According to our FT-IR and Raman spectral analysis, the non-centrosymmetric vibration within the [WO4]2- complex gives rise to internal modes while the Ca2+/Sm3+ cationic displacement and rigid molecular ionic group constitutes the external modes which equally impacts the electronic and optical characteristics of the host material. While the forbidden gap extends due to Sm3+ substitution, the delocalization of W-5d orbitals on the other hand occur due to rising distortions within the WO4 cluster. As a result, the polarization between [WO4] and [CaO8] cluster and difference in the electronic transitions controls the optical characteristics of the host material. According to our experimental and theoretical predictions, a noticeable decrease in the optical band gap (5.96–5.83 eV) occurs due to heterovalent cationic substitution (Sm3+), difference in structural order-disorder and charge carrier density. As a result, a broad photoluminescence (PL) spectrum among acceptor doped samples verifies the impact of multi-phonon or multi-level processes on the luminosity of the host material.

The Effect of Cesium Incorporation on the Vibrational and Elastic Properties of Methylammonium Lead Chloride Perovskite Single Crystals.

Hybrid organic-inorganic lead halide perovskites (LHPs) have emerged as a highly significant class of materials due to their tunable and adaptable properties, which make them suitable for a wide range of applications. One of the strategies for tuning and optimizing LHP-based devices is the substitution of cations and/or anions in LHPs. The impact of Cs substitution at the A site on the structural, vibrational, and elastic properties of MAxCs1-xPbCl3-mixed single crystals was investigated using X-ray diffraction (XRD) and Raman and Brillouin light scattering techniques. The XRD results confirmed the successful synthesis of impurity-free single crystals, which exhibited a phase coexistence of dominant cubic and minor orthorhombic symmetries. Raman spectroscopy was used to analyze the vibrational modes associated with the PbCl6 octahedra and the A-site cation movements, thereby revealing the influence of cesium incorporation on the lattice dynamics. Brillouin spectroscopy was employed to investigate the changes in elastic properties resulting from the Cs substitution. The incorporation of Cs cations induced lattice distortions within the inorganic framework, disrupting the hydrogen bonding between the MA cations and PbCl6 octahedra, which in turn affected the elastic constants and the sound velocities. The substitution of the MA cations with smaller Cs cations resulted in a stiffer lattice structure, with the two elastic constants increasing up to a Cs content of 30%. The current findings facilitate a fundamental understanding of mixed lead chloride perovskite materials, providing valuable insights into their structural and vibrational properties.

Optimizing electromechanical properties of KNN-based piezoelectric ceramics through regulation of lattice distortion

With the rapid development of broadband transducers, there is an increasing demand for enhanced electromechanical properties in lead-free piezoelectric ceramics. In this study, the strategies to enhance the electrical properties of ceramics were explored by doping BaZrO3 into 0.96(K0.48Na0.52)Nb0.96Sb0.04O3-0.04(Bi0.5Ag0.5)ZrO3 ceramics, inducing lattice distortion (c/a) and regulating the phase structure. The ceramics doped with 1.5 mol% BaZrO3 demonstrate excellent electrical performance, with a piezoelectric coefficient (d33) of 545 pC/N, a relative dielectric constant (εr) of 4126, and an electromechanical coupling factor (kp) of 54.1 %. The reduced c/a ratio and rhombohedral-orthorhombic-tetragonal phase structure reduce the polarization energy barrier and promote the ordered arrangement of ferroelectric dipoles, thereby enhancing the comprehensive performance of the ceramics. Lastly, the electrical impedance of ceramics is studied in detail and reveals the main conduction mechanism in the microscopic region. This research provides new insights into optimizing the electrical properties of ceramics through microstructural manipulation and demonstrates the potential application of KNN-based ceramics in high performance piezoelectric transducers.

Electronic and optical properties of S vacancy and Br and I doped monolayer MoS2: A first-principle study

This study investigated the energy band structure (BS), electronic state density, and optical properties of monolayer molybdenum disulfide (ML-MoS2) with undoped, sulfur vacancy (VS), bromine (Br), and iodine (I) doped MoS2 systems using the first-principle approach based on density functional theory (DFT). Our results show that compared to undoped MoS2 system, Br, and I doped MoS2 systems induced lattice distortions. In addition, and the bandgap widths was reduced in VS, Br, and I doped systems, thereby effectively suppressing the compounding of electron–hole pairs. Moreover, the recombination rate of electron–hole pairs was reduced, which in turn increased the mobility of electrons transferred from the valence band (VB) to the conduction band (CB). Moreover, the VS and Br doped systems exhibited superior optical properties compared to undoped MoS2 system. Notably, the VS system exhibited the best optical properties, thereby demonstrating the strongest polarization capability. Our findings pave the way for realizing electronic devices and photocatalytic materials on MoS2 nanostructures.

Effect of Pr3+ doping on relaxation behavior and strain response of PHT-based piezoelectric ceramics

Heterovalent ion doping has influenced the further development of piezoelectric applications. Pr3+ doping in relaxor ferroelectrics is rarely focused on piezoelectric performance enhancement. 0.51 Pb(Ni1/3Nb2/3)O3-0.49 Pb(Hf0.3Ti0.7)O3 (PNN-49PHT) ceramics with Pr3+ doping ceramics were designed and fabricated by a two-step precursor method. Excellent dielectric diffusion coefficient (γ) of 1.96 was achieved at the low Pr3+ doping concentration of 0.2 %. Increased relaxation enhanced the nanoscale domains formation, resulting in a giant strain response (d*33) of 1400 pm/V at 10 kV/cm, and a total strain (Stol) of 0.27 % at 20 kV/cm. Structural refinement unveiled that the high piezoelectricity originated from the mainly substitution of Pr3+ for Pb2+ at the A-site, inducing lattice distortion and phase transitions. Local domain switching and long-range ordered destruction were investigated by piezoresponse force microscopy (PFM) and Scanning Electron Microscopy (SEM). These findings contribute to the advancement of piezoelectric devices and provide valuable insights for the design and optimization of high-performance piezoelectric ceramics.

The influence mechanisms of re-fused scanning on the surface roughness, microstructural evolution and mechanical properties of laser powder bed fusion processed AlMgScZr alloy

Laser powder bed fusion (LPBF) stands out as the foremost method for achieving intricate structure with superior design flexibility among additive manufacturing technologies. Within the LPBF process, surface roughness serves as a critical metric governing both fabrication precision and build quality. This study delves into the evolution of the top and side surface roughness as re-fused scanning times increase in LPBF-fabricated AlMgScZr alloy. Concurrently, the investigation evaluates alterations in microstructural characteristics and mechanical properties. Various characterization techniques, including confocal laser scanning microscope, scanning electron microscope, X-ray diffraction, electron backscatter diffraction, as well as tensile and microhardness tests, are employed. The findings concerning the top surface reveal that the initial application of re-fused scanning contributes to enhanced surface roughness. This improvement stems from refined grain structures and induced lattice distortions, facilitated by rapid heat dissipation and thermal recycling within the solidified layer. Consequently, microhardness increases. However, introducing the subsequent re-fused scanning exacerbates surface roughness and instigates Marongoni flow instability, magnesium depletion, and alterations in lattice structures. Moreover, with increasing the re-fused times, there is a noticeable enhancement in preferential crystallite growth orientation along the (200)α-Al crystal plane. Regarding the side surface, escalating re-fused times correlate with deteriorating roughness and alterations in molten pool shape and size, attributable to successive energy input. Despite these surface variations, minimal differences are observed in yield strength, tensile strength, and elongation. In essence, this research offers valuable insights into selecting optimal scanning methodologies during the LPBF process, thus guiding improvements in fabrication precision and component quality.

Thermal Conductivity and Sintering Mechanism of Aluminum/Diamond Composites Prepared by DC-Assisted Fast Hot-Pressing Sintering.

A novel DC-assisted fast hot-pressing (FHP) powder sintering technique was utilized to prepare Al/Diamond composites. Three series of orthogonal experiments were designed and conducted to explore the effects of sintering temperature, sintering pressure, and holding time on the thermal conductivity (TC) and sintering mechanism of an Al-50Diamond composite. Improper sintering temperatures dramatically degraded the TC, as relatively low temperatures (≤520 °C) led to the retention of a large number of pores, while higher temperatures (≥600 °C) caused unavoidable debonding cracks. Excessive pressure (≥100 MPa) induced lattice distortion and the accumulation of dislocations, whereas a prolonged holding time (≥20 min) would most likely cause the Al phase to aggregate into clusters due to surface tension. The optimal process parameters for the preparation of Al-50diamond composites by the FHP method were 560 °C-80 MPa-10 min, corresponding to a density and TC of 3.09 g cm-3 and 527.8 W m-1 K-1, respectively. Structural defects such as pores, dislocations, debonding cracks, and agglomerations within the composite strongly enhance the interfacial thermal resistance (ITR), thereby deteriorating TC performance. Considering the ITR of the binary solid-phase composite, the Hasselman-Johnson model can more accurately predict the TC of Al-50diamond composites for FHP technology under an optimal process with a 3.4% error rate (509.6 W m-1 K-1 to 527.8 W m-1 K-1). The theoretical thermal conductivity of the binary composites estimated by data modeling (Hasselman-Johnson Model, etc.) matches well with the actual thermal conductivity of the sintered samples using the FHP method.

In-situ reconstruction of LaCoO3-Co3O4 hetero-interface over lanthanum modified Co3O4 nanocatalyst for improved catalytic activity and sintering resistance in methane combustion

Nanoparticles-based catalysts still suffer from deactivation due to sintering and structural collapse through long-time running at high reaction temperature. Developing simple strategy for improving the sintering resistance of nanoparticles is of great importance for fabrication of durable heterogeneous catalysts. In this work, lanthanum was used to prevent Co3O4 nanoparticles from sintering with restricting growth of nanocrystals by in-situ generation of LaCoO3 perovskite phase during thermal ageing process, further building LaCoO3-Co3O4 hetero-interface with strong interfacial effect. Specifically, the Co3O4 nanocatalyst was loaded with different amount of La by traditional impregnation method and a series of characterizations were carried out to explore the physical and chemical properties of the as-prepared catalysts, including XRD, Raman, BET, SEM, HRTEM, XPS, H2-TPR and O2-TPD. It was found that 5 wt% La-Co3O4 has the highest catalytic activity in CH4 combustion and the value of T90 (temperature of 90% methane conversion) between fresh and aged was only 9 ºC, while this value was 108 ºC over pure Co3O4 sample. The Raman, XPS, H2-TPR and O2-TPD results exhibited that the synergistic effect between Co3O4 and LaCoO3 could not only induce lattice distortion in Co3O4 with more defects and adsorbed oxygen species, enhanced oxygen mobility and reducibility, but also significantly suppress the growth of Co3O4 nanocrystals during thermal ageing treatment.

Inhibition strategies for phase separation of iron-based oxygen carriers in chemical looping gasification- enhanced oxygen transport efficiency through oxide-support interactions

Chemical looping gasification partially oxidizes biomass to obtain high-quality syngas using oxygen carriers, emerging as a potential method to cope with energy shortages. However, the oxygen carriers were susceptible to deactivation due to phase separation caused by different migration rates between atoms. In this work, the phase deviation of the oxygen carrier is inhibited by enhancing the lattice oxygen activity. Typically, the NiFe-based oxygen carriers were used as active sites and Ce atoms were introduced to change the lattice structure of the oxygen carriers. Calculated by density functional theory (DFT), Ce atoms formed a strong bonding interaction (Ni-O-Ce) with Ni atoms, causing lattice distortion of NiFe oxygen carriers that promote the formation of oxygen vacancies. Therefore, the syngas yields were increased from 537 ml/g (NF) to 633 ml/g (NF@0.5Ce) and 615 ml/g (NF@1.5Ce) in the N2 atmosphere. The syngas yields were increased from 895 to 1101 ml/g (NF@0.5Ce) and 1186 ml/g (NF@1.5Ce) with steam atmosphere. During the 20-cycle experiments, the phase separation of NiFe-based oxygen carriers was effectively suppressed by the intervention of Ce atoms. Therefore, it is a feasible option to induce lattice distortion of active grains by introducing inert elements to suppress phase separation.

Revealing the Potential and Challenges of High‐Entropy Layered Cathodes for Sodium‐Based Energy Storage

AbstractSodium‐ion batteries (SIBs) reflect a strategic move for scalable and sustainable energy storage. The focus on high‐entropy (HE) cathode materials, particularly layered oxides, has ignited scientific interest due to the unique characteristics and effects to tackle their shortcomings, such as inferior structural stability, sluggish reaction kinetics, severe Jahn‐Teller effects induced lattice distortion, and poor oxygen reversibility at high voltage. This review focuses on high‐entropy oxide materials, highlighting their fundamentals, design principles, and application in layered oxide cathodes for SIBs. It delves into the growth mechanism, composition‐properties correlations, and the functional roles of high‐entropy design in enhancing the performance of layered oxide cathodes. Furthermore, it furnishes a comprehensive survey of recent advancements and persisting challenges within the domain of layered high‐entropy cathode materials, as well as offers insights into potential future research directions in line with the current state of knowledge.

High-entropy strategy for high-temperature broadband infrared radiation and low thermal conductivity

Developing high-performance infrared radiation ceramic materials with desired broadband emissivity while reducing thermal conductivity to prevent heat transfer is highly desirable for emerging industrial and aerospace applications. Nevertheless, it remains a grand challenge to simultaneously meet these requirements in existing infrared radiation ceramic materials. Herein, a high-entropy strategy is employed to enhance the high-temperature infrared radiation property with a high emissivity above 0.9 at room temperature and 0.68 at 1200 °C across the entire range of wavelength (1–14 μm), and integrate a low thermal conductivity (<0.88 W m−1 K−1 at 1000 °C) and remarkable mechanical properties. High-entropy rare earth (RE) disilicates ((Y0.4Yb0.4Tm0.1Lu0.05Ho0.05)2Si2O7) ceramic coating with high lattice entropy has a more complex electronic structure, inducing lattice distortion and extra multi-mode vibrations, which boosts the emissivity in mid-infrared range (3–14 μm). Meanwhile, the high-entropy strategy prompts the formation of impurity energy levels as gap states, achieving optical absorption at low photon energies, and thus enhancing the emissivity in near-infrared range (1–3 μm). Simultaneously, (Y0.4Yb0.4Tm0.1Lu0.05Ho0.05)2Si2O7) ceramic coating owns diffusion-mediated thermal transport properties with strong phonon scattering, assisted further by the lamellar porous structure, thereby enabling a low thermal conductivity. The excellent mechanical properties ensure the reliability of the coating in extreme environments. All these merits render the high-entropy ceramic coating competitive for the development of high-temperature broadband high-emissivity thermal radiation materials.

Unraveling the mechanism of vanadium self-intercalation in 1T-VSe2: atomic-scale evidence for phase transition and superstructure model for intercalation compound

Self-intercalation is an efficient strategy for tailoring the property of layer structured materials like transition metal dichalcogenides (TMDCs), while the associated kinetics and mechanism remain scarcely explored. In this study, we investigate the atomic-scale dynamics and mechanism of vanadium (V) self-intercalation in multi-layer 1T-VSe2 using in situ high resolution scanning transmission electron microscopy. The results reveal that the self-intercalation of V induces structural transformation of pristine VSe2 into three V-enrich intercalated compounds, i.e. V5Se8, V3Se4 and VSe. The self-intercalated V follows an ordered arrangement of 2×2 , 2×1 , and 1×1 within the interlayer octahedral sites, corresponding to an intercalation concentration of 25%, 50% and 100% in V5Se8, V3Se4 and VSe, respectively. The V intercalants induced lattice distortions to the host 1T-VSe2 such as the dimerization of neighboring lattice V is observed experimentally, which are further supported by density functional theory (DFT) calculations. Finally, a superstructure model generalizing the possible structures of self-intercalated compounds in layered TMDCs is proposed and then validated by the DFT determined formation energy landscape. This study provides comprehensive insights on the kinetics and mechanism of the self-intercalation in layered TMDC materials, contributing to the precise control for the structure and stoichiometry of self-intercalated TMDC compounds.

Fabrication, sintering behavior and mechanical properties of calcium oxide doped yttrium oxide refractory via aqueous gel casting method

Yttrium oxide is an ideal choice for titanium aluminum alloy melting and casting, its wider use is hindered by sintering challenges and low thermal shock resistance. To address this, we propose a gel casting method for calcium oxide-doped yttrium oxide production. We pretreated yttrium oxide with phosphoric acid to prevented hydrolysis and adjusted the isoelectric point of yttrium oxide to match calcium carbonate's. Anions from calcium carbonate increased slurry solid content (up to 58 vol%) while maintaining low viscosity (57.78 mPa·s at 40 s−1 shear rate). After sintering at 1650 °C for 2 h, the material showed a flexural strength of 78 MPa, with a 90% retention rate after thermal shock test. The introduction of calcium oxide induced lattice distortion, improving mechanical properties by aiding sintering and grain boundary diffusion. XPS and STEM analysis confirmed random replacement of Y3+ by Ca2+ at the C2 position with 1 wt% doping.

High-efficiency CO2 conversion via mechano-driven dynamic strain engineering of ZnO nanostructures

Strain engineering involves intentionally inducing lattice distortion in materials to manipulate their electronic and geometric properties, along with the accompanying bond strength between reactants and catalysts. This approach presents an appealing pathway to optimize catalytic performance. However, it confronts challenges in achieving precise control, scalability and controllable modulation of intermediate species’ adsorption and desorption. Herein, we report a dynamic strain engineering method achieved through ultrasonic cavitation-induced high and low-pressure cycles, enabling periodically adjustable adsorption/desorption properties while bypassing complex synthesis procedures. Illustrated using ZnO and CO2 piezo-reduction reaction as a demonstration, theoretical studies initially predict that adsorption of intermediates *COOH can be regulated within a specific range of strains. Under ultrasonic stimulation, ZnO catalyst with dynamic strain engineering exhibits a CO yield of ∼ 98.8 μmol·g−1·h−1, approximately 16.5 times higher than that achieved under ultraviolet light irradiation without dynamic strain engineering, despite the latter having a considerably stronger input power. Furthermore, we delve into the factors linked to dynamic strain amplitude and frequency. This dynamic strain engineering approach streamlines catalyst preparation and presents innovative possibilities for controlled manipulation of intermediate specie’s adsorption/desorption, with potential applications across a wide range of catalytic systems.