Octahedral Bond Research Articles

Effect of divalent ion of strontium substitution on the structural, optical, magnetic and blood compatibility studies in cobalt ferrite

This study investigates the effects of Sr2+ substitution on the structural, morphological, and magnetic properties of magnetic cobalt ferrite (CoFe2O4). Through sol–gel auto-combustion synthesis, Sr2+ was substituted into Co-spinel ferrites (Co1-xSrxFe2O4, where x = 0.0, 0.25, 0.5, 0.75, 1.0). SEM analysis revealed spherical grains with an average size of 54.4 nm. XRD analysis indicated systematic changes in crystallographic parameters and the formation of secondary phases with Sr-substitution. While the crystal size for CoFe2O4 was calculated as 262 nm, this value was determined as 18 nm for Co0.25Sr0.75Fe2O4. FT-IR results suggested increased force constants of octahedral and tetrahedral bonds with higher Sr content, with main vibration bands at 423.6 and 606 cm−1. M-H curves exhibited S-shaped behavior, indicating drastic magnetic property changes with Sr2+ substitution. Coercivity field (Hc), saturation magnetization (M S ), and remanent magnetization (M r ) values ranged from 1447.8–545.4 Oe, 58.8-14 emu g−1, and 36.8-7.6 emu g−1, respectively. Blood compatibility experiments highlighted Co0.75Sr0.25Fe2O4 nanoparticles with significantly low hemolysis rates compared to other concentrations.

Effect of rare earth (Sm3+) substitution in mixed Ni-Zn-Co ferrites: Structural, magnetic, and DC electrical resistivity studies

NiZnCo ferrite has good magnetic properties and is one of the core materials used in magnetic devices. The solid-state reaction approach is utilized to synthesize Ni0.4Zn0.35Co0.25Fe2-xSmxO4 (x = 0.0, 0.02, 0.04, 0.06, 0.08, and 0.1) ferrites for investigation of structural, morphological, functional, magnetic and electrical resistivity properties using various characterization techniques. The techniques used for characterization were XRD, SEM, FTIR, VSM, and DC electrical resistivity. XRD spectra were used to determine phase confirmation, cubic crystallite size, andtheir variation with dopant content. No additional phase or impurity was found. The SEM pictures revealed ahomogeneous spherical particle formation with minimal porosity. With absorption bands under 1000 cm−1, FTIR spectra indicate the formation of a spinel structure. Tetrahedral (580 to 599 cm−1) and octahedral (388 to 399 cm−1) bond changes can be seen in infrared spectra. The magnetic hysteresis curves revealed soft ferromagnetic behavior, with coercivity (Oe) (532.13 to 312.10Oe) rising and saturation magnetization (Ms) (83.51 to 60.75 emu/g) falling as doping concentration increased. The DC electrical resistivity of synthesized nanoparticles with various compositions was measured against higher temperatures to confirm their semiconductor nature. The findings demonstrated the typical decreasing trend with rising temperature.

Regulating structural stability and photoelectrical properties of FAPbI3via formamidine cation orientation.

Organic cations play a significant role in the structural stability and photoelectrical properties of organic-inorganic hybrid perovskites. The orientation of organic cations impacts its interaction with inorganic octahedrons [PbI]6-, subsequently modifying the atomic structure and electronic and optical properties of perovskite materials. However, it is still challenging to regulate the stability of perovskites with different orientations. In this work, density functional theory calculations were performed to investigate the effects of the formamidine cation (FA+) located at the angles of 0°, 45°, 90° and 180° (relative to the normal of the crystal plane) along the typical crystal directions ([001], [010], [110] and [111]) on the structural stability and photoelectrical properties of formamidine lead iodide (FAPbI3). The results show that when FA+ is located at 45° along the [111] direction, FAPbI3 achieves the highest stability and excellent photoelectrical properties. The energy evolution curves display that the system with the orientation of [111] has the minimum energy value, signifying stronger stability than the other orientations. Especially, when FA+ is located at 45° along the [111] direction. it exhibits a stronger hydrogen bond between H and I atoms, shorter Pb-I bond length and smaller [PbI]6- octahedral tilt bond angle. The band gap in the [110] direction changes from direct to indirect while FAPbI3 with other FA+ orientations still maintains the direct band structure located at the high symmetric R point. Furthermore, FA+ orientation drives the redshift of FAPbI3 towards the long wavelength region in the [111] crystal direction, which enhances the light absorption coefficient. This work can offer guidance in employing molecular regulation technology for the development of stable perovskite solar cells.

Mössbauer analysis, structural parameter studies and magnetic properties of LiCoxFe5-xO8 (x= 0, 0.025, 0.05, 0.075, 0.1) nanoparticles

We report on detailed structural parameter analysis, Mössbauer spectra and magnetic properties of LiCoxFe5-xO8 (x = 0, 0.025, 0.05, 0.075, 0.1) nanoparticles prepared by sol-gel method. Prepared LiCoxFe5-xO8 nanoparticles crystalizes in inverse spinel structure with the crystallite size ranging from 23.7 to 29.8 nm. Hopping length, radii of tetrahedral and octahedral sites (rA and rB), tetrahedral bond length (dAx), octahedral bond lengths (dBx), tetrahedral and octahedral shared edges (dAxE, dBxE), unshared octahedral edges (dBxEU) values and oxygen positional parameter (u) are seen to increase with increasing Co concentration. Chemical state of all the elements are confirmed by X-ray photoelectron spectroscopy technique. The hyperfine field, isomer shift, quadrupole shift and line width parameters calculated from the Mössbauer spectra confirms the Co2+ substitution in LiFe5O8. The saturation magnetization value decreases from 59.2 to 54.1 emu/g with increasing Co concentration, which is examined by three sublattice model derived by Yafet and Kittel (Y-K model). Y-K angles increases with Co concentration from 16.46 to 19.98°. Curie temperature of LiFe5O8 decreases from 865 K to 858 K with increasing Co concentration to x = 0.1.

Composition‐dependent thermal and thermomechanical properties of spinel‐type MgAlON from density functional calculation

AbstractAs ceramics based on magnesium aluminum oxynitrides solid solutions are promising materials as refractories, windows/armors, phosphors, and so forth, it is essential to explore their thermal and thermomechanical properties, owing to the physical requirements on application. In this study, Mg5xAl23−5xO27+5xN5−5x were chosen for the investigation on composition‐dependent thermal and thermomechanical properties by the theoretical calculations. Though the binary system with octahedral bonds contributes more to the thermal expansion coefficient of Mg5xAl23−5xO27+5xN5−5x, the binary system with tetrahedral bonds plays an important role in the variation of the thermal expansion coefficient. The change of heat capacity with the rise of x is mainly attributed to the variation of covalent character of Mg5xAl23−5xO27+5xN5−5x. Moreover, the thermal conductivity is mainly affected by the scattering from atoms in 8a sites. Both thermal and mechanical properties contribute to the variation of thermomechanical properties of Mg5xAl23−5xO27+5xN5−5x. This study can provide guidance to designing spinel materials with desirable thermal and thermomechanical properties for application.

Analyzing the atomic pair distribution function of BMT-based nanopowders via X-ray diffraction

In this study, we investigate the three-dimensional atomic structure of 0.65[Ba(Mg1/3, Ti2/3)]−0.35[BaTiO3] (BMT-BT) using x-ray diffraction (XRD) with molybdenum radiation (MoKα 1), Rietveld refinement, and the atomic pair distribution function (PDF) technique. We provide an analysis of the advantages of the PDF method for studying the unit cell of electroceramics. The XRD results show that BMT has a bulk crystal structure with a cubic perovskite structure. The new structural information enhances our understanding of the dielectric properties of BMT. The PDF analysis reveals that the average interatomic bond distance in the octahedral TiO6 atomic bond is around 2.8 Å, and the first peak at r = 1.39 Å corresponds to the nearest neighbor M-O distance (M = Ti, Mg, Nb). Additionally, the peak at r = 2.4 Å corresponds to the Ba-O and O-O distances in the MO6 octahedron. Peaks in the PDF data below 1 Å are ignored as they have no physical implications.

Crystal Structure, Chemical Bond, and Microwave Dielectric Properties of Ba1-xSrx(Zn1/3Nb2/3)O3 Solid Solution Ceramics.

Ba1-xSrx(Zn1/3Nb2/3)O3 (BSZN) perovskite ceramics are prepared using the traditional solid-state reaction method. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) were used to analyze the phase composition, crystal structure, and chemical states of BSZN ceramics, respectively. In addition, the dielectric polarizability, octahedral distortion, complex chemical bond theory, and PVL theory were investigated in detail. Systematic research showed that Sr2+ addition could considerably optimize the microwave dielectric properties of BSZN ceramics. The change in τf value in the negative direction was attributed to oxygen octahedral distortion and bond energy (Eb), and the optimal value of 1.26 ppm/°C was obtained at x = 0.2. The ionic polarizability and density played a decisive role in the dielectric constant, achieving a maximum of 45.25 for the sample with x = 0.2. The full width at half-maximum (FWHM) and lattice energy (Ub) jointly contributed to improving the Q × f value, and a higher Q × f value corresponded to a smaller FWHM value and a larger Ub value. Finally, excellent microwave dielectric properties (εr = 45.25, Q × f = 72,704 GHz, and τf = 1.26 ppm/°C) were obtained for Ba0.8Sr0.2(Zn1/3Nb2/3)O3 ceramics sintered at 1500 °C for 4 h.

Studying the structural properties of Mg-Zn ferrite nano partical prepared by auto combustion Sol-gel method

In the present work the Magnesium-zinc ferrite chain ( Mg1-xZnxFe2O4) with x=0-1,were synthesized using sol-gel auto combustion as a modern chemical ‎methods .Nitrates, citric acid and ammonia were used ‎in order to get ferrite nano powders at temperature 2200C , which characterized a higher dispersion ‎and homogeneity with particle size in the range of (27.47-68.9) nm. The obtained ferrite nano powder calcined at temperature 5000C for a period three hours .
 Samples examined by Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). From FTIR spectral analysis the structure of the spinel ferrites shows two absorption bands, , due to vibration of octahedral and tetrahedral metal oxygen bonds. SEM results show the presence of uniformly distributed and almost spherical shaped particles

Photocatalytic Removal of Methylene Blue Dye Using CoZnFe<sub>2</sub>O<sub>4</sub>/SiO<sub>2</sub> Magnetic Nanoparticles

The magnetic photocatalyst of CoZnFe2O4/SiO2 nanoparticles has been synthesised to degrade methylene blue (MB) dye. The CoZnFe2O4 nanoparticles were prepared by co-precipitation method under mechanical stirring and coated with SiO2 by stöber method using Na2SiO2 with various concentrations of 5%, 10%, 15%, 20%, 30%, and 50%. The properties of CoZnFe2O4/SiO2 was confirmed by x-ray diffraction (XRD), Fourier transforms infrared (FTIR), vibrating sample magnetometer (VSM), and UV-Visible spectroscopy. XRD analysis revealed that CoZnFe2O4 had the spinel ferrite phase structure with crystalite size of 17.0 nm, and then after coating with SiO2, the size became 17.1 nm. FTIR clearly show an M-O octahedral vibrational bond found with a wavelength of 378 cm-1, O-Si-O, Si-OH, and Si-O-Fe at 1087, 794, and 570 cm-1, respectively. The saturation magnetization (Ms) and coercivity of CoZnFe2O4/SiO2 was 29.0 emu/g and 251.9 Oe, respectively. Furthermore, the results of UV-Visible data presented that the absorption edges CoZnFe2O4/SiO2 in the range of 190 - 600 nm. The percentage of CoZnFe2O4 degradation is 88.4%, while after coted SiO2 50%, the degradation becomes 98.9%.

High-Q×f value and temperature stable MgZrTa2O8 ceramics by Li heterovalent substitution

The Mg1-xLixZrTa2O8-x/2 (x = 0–0.07) ceramics were fabricated to investigate the effects of Li+ heterovalent substitution for Mg2+. The site occupancy and existence of the Li+ were examined based on Vienna Ab-initio Simulation Package (VASP) and X-ray photoelectron spectroscopy (XPS), respectively. Single phase solid solution with wolframite structure was identified in the whole region. Li+ substitution reduced the densification temperature from 1475 °C to 1400 °C. Notably, the Q×f exhibited an obvious increase by up to 74 % from 41,844 GHz at x = 0–72,782 GHz at x = 0.05. The Q×f for x < 0.01 was largely dependent on the intrinsic loss originating from packing fraction, while as 0.01 ≤ x ≤ 0.05, it was dominated by extrinsic factors, especially the oxygen vacancy concentration. The corresponding dielectric constant εr decreased in term of ionic polarizability. The variations of resonant frequency temperature coefficient τf were explained from the views of [TaO6] oxygen octahedral distortion and bond energy. A near-zero τf was obtained for x = 0.05 composition, accompanied by εr = 11.97, Q×f= 72,782 GH at 1450 °C. Li substitution was effective and inexpensive for MgZrTa2O8 ceramic to realize dielectric properties enhancement and densification temperature optimization simultaneously.

Structural, Magnetic and Dielectric Properties of Ni0.3Cu0.7CoxCrFeO4 Sol-gel Synthesized Nano Thin Films

A thin magnetic oxide layer with composition Ni0.3Cu0.7CoxCrFeO4 (0.0&lt;x&lt;1) is produced by the SILAR process. X-ray diffraction, cation distribution and infrared spectra were investigated as structural features. Permittivity and dissipation factor are properties of interest. Magnetic properties were studied using MOKE. The lamellae have been shown to have spinal structures. As Co grows, the lattice constant also increases. Observed I.R. spectra show tetrahedral and octahedral bonds. Increase in the dielectric properties because enhancement of space charge polarization.

Effect of rare earth doping on magnetic and dielectric properties of NiZnMn ferrites

In present work, RE0.01Ni0.3Zn0.4Mn0.3Fe2O4 (RE=Fe, La, Nd, Sm, Gd, Dy, Yb) ferrites with strictly controlled main composition were prepared. X-ray diffraction analysis shows that the lattice constant decreases with the increase of atomic number of rare earth. The infrared spectra demonstrate the changes of tetrahedral and octahedral bonds. The saturation magnetization is about 74 emu/g and initial permeability is about 120 for undoped ferrite. They decrease slightly after rare earth doping, but the impact of different rare earth on Ms is same. The Curie temperature of almost all samples is 262 ℃. Zero field cooling-field cooling curves demonstrate the existence of spin glass state or superparamagnetism at high temperature. Sm, Gd and Dy doped ferrites have special dielectric properties with more relaxation processes. Appropriate rare earth doping greatly improve the cut-off frequency, dielectric constant for MHz device materials and dielectric loss for GHz electromagnetic wave absorption materials.

Mn-doping Ca2Fe2O5-based oxygen carriers in chemical looping gasification of biogas residue: A comprehensive study on the reaction mechanisms

The disposal of solid residues from the anaerobic digestion to generate biogas remains a serious challenge, which can be beneficially solved to generate the syngas based on gasification technologies. Among of them, chemical looping gasification (CLG) of biogas residues likely achieves the high-quality syngas production using the oxygen carriers (OCs). Since the nature of the solid–solid contact in CLG reactions resulting in greatly worsening reaction rates and syngas product quality, the development an oxygen-uncoupling type OCs is highly demanding. This study introduces the preparation, characterizations and performance evaluation on Bi-functional Mn/Ca2Fe2O5 oxygen carriers (OCs) achieving the oxygen-uncoupling and catalytic CO2 conversion to CO. The Mn-doping Ca2Fe2O5-based OCs with Mn in 20 mol.% (20MnCaFe) achieves an optimal gasification efficiency, carbon conversion efficiency in 72.31% and 95.72% respectively with lower CO2 yield. The intensive characterization of used OCs revealed that the proper Mn-doping helped on the increase of d-spacing, corresponding to more high-charge Mn ions and improved oxygen-ion migration and oxygen activation, and thus greater oxygen evolution reaction performance, and the incorporation of Mn in Mn/Ca2Fe2O5, leading the structural distortion of octahedral Fe-O bond and the stronger oxycarbide adsorption ability. Studies confirmed the correspondence of 20MnCaFe to its capabilities of optimal oxygen uncoupling, catalytic conversion of CO2 to CO and the coordinated oxidability, resulting in the improvement of syngas quality. A clear reaction pathway involving Mn/Ca2Fe2O5 in CLG is exhibit, that is oxygen uncoupling, CO2 catalytic conversion, the regeneration of oxygen uncoupling vacancy and finally recoverable oxygen uncoupling.

Exciton-Phonon Coupling of Chiral One-Dimensional Lead-Free Hybrid Metal Halides at Room Temperature.

The interaction between organic cations and inorganic metal halide octahedral units strongly affects the properties of organic-inorganic hybrid metal halides. The "soft" property of the lattice provides the possibility of its strong exciton-phonon interaction. Here we report one-dimensional (1D) lead-free chiral organic-inorganic hybrid metal halide single crystals of (R/S)-methylbenzylamine bismuth iodide (R/S-MBA)2Bi2I8, which exhibits a high level of octahedral bond distortion. The introduction of chiral amines leads to a strong chiroptical response in the range of 200-600 nm. The strong exciton-phonon coupling can be observed through the coherent oscillation spectrum of transient absorption dynamics at room temperature. The coherent phonon oscillation frequencies are ∼97 and ∼130 cm-1, corresponding to the symmetrical stretching or bending of the Bi-I octahedron. Our work provides new insights for the study of exciton-phonon coupling in 1D chiral hybrid metal halides.

Minimum hysteresis loss and amplified magnetic properties of superparamagnetic Ni–Zn nano spinel ferrite

Nanocrystalline NixZn1-xFe2O4 ferrite was prepared using the microwave-assisted sol-gel auto combustion method. The nanocrystalline ferrite was characterized by powder XRD, SEM, FT-IR, VSM, Mossbauer, magnetic and dielectric study. The lattice constant, tetrahedral radius, octahedral radius, anion parameter, average crystalline size, tetrahedral bond length, octahedral bond length, and deviation parameter have been estimated from XRD and compared with standard results. The magnetic properties of the prepared ferrite were studied and parameters like saturation magnetization, magnetic remnant, magnetic moment, coercivity, and SQR were estimated. The effect of substitution on isomer shift and magnetic exchange interaction between octahedral and tetrahedral sites on magnetic properties were discussed from Mossbauer’s study. It was observed that the isomer shift does not vary appreciably with a concentration of nickel in zinc lattice. Moreover, the exchange interaction between Fe3+ ions at tetrahedral and octahedral sites and the doped nickel ions prefer the octahedral sites that strongly favor the magnetic interactions. The temperature dependence AC susceptibility was measured to know the magnetic phase transition. The dielectric constant and tangent loss are high at lower frequencies, decreasing with frequency and finally becoming almost constant. The dielectric constant ε′ was also found to increase with the increase in Ni2+ content.

Eco-friendly synthesis of cobalt-zinc ferrites using quince extract for adsorption and catalytic applications: An approach towards environmental remediation

Cobalt-zinc ferrite nanoparticles were synthesized using environmentally friendly approach with quince extract as a reducing agent. Crystal structure and morphology of the obtained materials were studied by XRD, SEM-EDS, Mössbauer and IR spectroscopy. The synthesized nanoparticles have a cubic spinel structure and crystallite size ranging from 5 to 9 nm. The infrared spectra contain characteristic absorption bands for the MA-O (∼560 cm−1) and MB-O bonds (∼420 cm−1). Force constants were calculated for both tetrahedral and octahedral bonds. As the Co content increases, the force constant for the tetrahedral bond increases and the force constant for the octahedral bond decreases. The obtained ferrite nanoparticles have good magnetization as shown by VSM (in the range from 36 to 67 emu/g). Magnetic nanoparticles CoxZn1-xFe2O4 were also tested for induction heating with electromagnetic field. The sample with x (Co) = 0.4 has the highest specific absorption rate. The synthesized samples were tested as adsorbents using the Congo Red dye as model pollutant. The best adsorbent was pure zinc ferrite with the adsorption capacity of 24.7 mg/g. The catalytic activity of the obtained ferrites for the decomposition of H2O2 was studied as well. The most active catalyst was pure cobalt ferrite. Probably, the active centers are octahedral cobalt ions. Thus, the obtained magnetic nanoparticles can be used for the adsorptive removal of pollutants, catalytic decomposition of the H2O2 and low-frequency hyperthermia.

An exsolution constructed FeNi/NiFe2O4 composite: preferential breaking of octahedral metal-oxygen bonds in a spinel oxide.

Exsolution is an ingenious strategy for the in situ construction of metal- or alloy-decorated oxides and, due to its promising energy related catalysis applications, has advanced from use in perovskites to use in spinels. Despite its great importance for designing target composites, the ability to identify whether active metal ions at octahedral or tetrahedral sites will preferentially exsolve in a spinel remains unexplored. Here, an inverse spinel NiFe2O4 (NFO) was employed as a prototype and FeNi/NFO composites were successfully constructed via exsolution. The preferential breaking of octahedral metal–oxygen bonds in the spinel oxide was directly observed using Mössbauer and X-ray absorption spectroscopy. This was further verified from the negative segregation energies calculated based on density-functional theory. One exsolved FeNi/NFO composite exhibits enhanced electrochemical activity with an overpotential of 283 mV at 10 mA cm−2 and a long stability time for the oxygen evolution reaction. This work offers a unique insight into spinel exsolution based on the preferential breaking of chemical bonds and may be an effective guide for the design of new composite catalysts where the desired metal ions are deliberately introduced to octahedral and/or tetrahedral sites.

Structural, optical and magnetic properties of nanocrystalline zinc ferrite particles from glycine assisted combustion: Effect of Sr2+ dopant

Abstract Spinel type pure and Sr2+ doped zinc ferrite nanoparticles were prepared by glycine assisted combustion. The resultant nanoparticles were found to be highly crystalline with cubic crystal structure. The structure and the corresponding changes in the tetrahedral and octahedral bond stretching were investigated. The chemical elements and oxidation states of these nanoparticles were determined and the elemental compositions of synthesized nanoparticles established. It was observed that the optical band gap values increased from 2.43 eV to 2.49 eV as Sr2+ concentration increased. The morphology, chemical elements and composition of the prepared ferrites were examined. The magnetic behavior of these nanoferrites was studied and corresponding changes in the saturation magnetization, coercivity and remanent magnetization were analyzed.

Chemistry-dependent Raman spectral features of glauconite and nontronite: Implications for mineral identification and provenance analysis

Abstract This study provides a comprehensive Raman spectral characterization of nontronite and glauconitenontronite mixed-layer phases from seafloor hydrothermal fields. These 2:1 phyllosilicates, which show isomorphous cation exchange between Mg2++Fe2+ and Fe3++Al3+ in the dioctahedral sheets, exhibit three diagnostic Raman peaks in the low wavenumber region (v1 ~241–257 cm−1; v2 ~600–606 cm−1; v3 ~690 cm−1), and one peak at ~3548–3570 cm−1 (v4). With increasing (Mg2++Fe2+)oct, the presumed stretching band of octahedral OH-O bonds (v1) is displaced to a higher wavenumber, whereas the stretching band of tetrahedral Si-O-Si bonds (v2) is shifted to a lower wavenumber. Peak v4, which relates to O-H bonds of hydroxyls linked to octahedral cations, shows a downshift with increasing (Mg2++Fe2+)oct. The band v4 can be mathematically fitted by three bands, two of which strongly correlate with the cation occupancy in the octahedral sheets; i.e., vibrations of hydroxyls linked to triva-lent cations (Fe3+ and Al3+) are mainly represented by a band at ~3560–3573 cm−1, whereas divalent cations (Mg2+ and Fe2+) mainly contribute to a band at ~3538–3540 cm−1. This result is consistent with theoretical considerations for dioctahedral phyllosilicates, which predict for the incorporation of Mg2+ and Fe2+ a weakening/lengthening of O-H bonds in the OH groups, accounting for a downshift of the O-H vibrations. Hence, this is one of the first studies that trace how even subtle chemical modifications in phyllosilicates influence Raman spectral features. The reported findings have implications for mineral identification and provenance analysis, such as during surface exploration on Mars, where compositionally diverse phyllosilicates occur.

Theoretical study on composition‐dependent properties of ZnO·nAl2O3 spinels. Part II: Mechanical and thermophysical

AbstractKnowledge on the mechanical and thermophysical properties of ZnO·nAl2O3 is essential for practical applications. Based on the first‐principles calculations and the bond valence method, the disordered spinel‐type structure of ZnO·nAl2O3 (n = 1–4) was constructed to investigate the composition‐dependent mechanical and thermophysical properties. The effects of cation substitution on the hardness, elastic modulus, thermal expansion, and thermal conductivity were revealed from the insights into the chemical bonds. At a higher n, the tetrahedral bond is stronger, manifested as its higher hardness and bulk modulus as well as smaller thermal expansion coefficient. Meanwhile, the octahedral bond is weaker, leading to the lower hardness and bulk modulus, along with the larger expansion coefficient. In consequence, the hardness and elastic moduli of ZnO·nAl2O3 are improved moderately while the expansion coefficient is decreased with the rise of n. Due to the different vibration characteristics of ZnIV and AlIV, the cation disorder in the 8a site provides the primary source of phonon scattering, resulting in the dramatic reduction of thermal conductivity as n increases. The understanding offers guidance on the application‐oriented design of new oxide spinels.