Change In Crystal Structure Research Articles

Study on fluorine vacancy defects in yttrium fluoride coating materials

Abstract Rare-earth fluoride coating materials have attracted wide attention as a substitute for ThF4 low-refractive index materials. However, the coating materials and coated films fail to achieve the desired results due to vacancy defects caused by their fluorine-loss decomposition characteristics. To explore the rare earth fluoride coating materials’ fluorine loss influence law, the melt crystallization method is used to simulate the yttrium fluoride (YF3) pre-melting process through the electronic paramagnetic resonance (EPR) obtained at different temperatures under the fluorine vacancy defects change rule. According to the number of unpaired spintrons, the number of spintrons in each vacancy is calculated. The results show that the fluorine vacancy defects increase with the increase of temperature, the formation of YF3 fluorine vacancy defects does not affect the change of crystal structure, and the addition of the additive ammonium hydrogen fluoride (NH4HF2) can reduce the oxygen content of YF3 and effectively inhibit the formation of fluorine vacancy. The effect is gradually obvious with the amount of additives added.

Valuation of the significant hypoglycemic activity of black currant anthocyanin extract by both starch structure transformation and glycosidase activity inhibition

The objective of this study was to investigate the impact of anthocyanin-rich black currant extract (BCE) on the structural properties of starch and the inhibition of glycosidases, gathering data and research evidence to support the use of low glycemic index (GI) foods. The BCE induced a change in the starch crystal structure from A-type to V-type, resulting in a drop in digestibility from 81.41 % to 65.57 %. Furthermore, the inhibitory effects of BCE on glycosidases activity (α-glucosidase: IC50 = 0.13 ± 0.05 mg/mL and α-amylase: IC50 = 2.67 ± 0.16 mg/mL) by inducing a change in spatial conformation were confirmed through in vitro analysis. The presence of a 5′-OH group facilitated the interaction between anthocyanins and receptors of amylose, α-amylase, and α-glucosidase. The glycosyl moiety enhanced the affinity for amylose yet lowered the inhibitory effect on α-amylase. The in vivo analysis demonstrated that BCE resulted in a reduction of 3.96 mM·h in blood glucose levels (Area Under Curve). The significant hypoglycemic activity, particularly the decrease in postprandial blood glucose levels, highlights the potential of utilizing BCE in functional foods for preventing diabetes.

The effects of polycrystalline 3 C-SiC with different roughness coefficients on the crystal structure of nano-grin ding based on molecular dynamics

To investigate the effect of different roughness subsurface on the crystal structure and grain boundary changes during polycrystalline 3 C-SiC nanocrystalline grinding. Polycrystalline 3 C-SiC with different roughness subsurface is constructed by Voronoi method, the stress, crystal structure change and grain boundary crossing mechanism of polycrystalline 3 C-SiC are analyzed by molecular dynamics method. Three different roughness surfaces (Ry=0.02 um, Ry=0.04 um and Ry=0.045 um) are selected for analysis, before the nano-grinding process, the polycrystalline 3 C-SiC is first annealed to make the atoms closely arranged and eliminate the vacancy defects inside the grains. Different roughness affects the friction force of polycrystalline 3 C-SiC and changes the deformation of its subsurface. Consequently, affecting the elastoplastic properties of polycrystalline 3 C-SiC. Different roughness will affect the shear force on the polycrystalline 3 C-SiC subsurface, the smaller the roughness, the greater the shear stress on the subsurface. The polycrystalline 3 C-SiC crystal structure with a roughness of Ry=0.04um is most obviously affected, the length of the dislocations it produces is relatively small, and the situation is more obvious at the boundary, fewer internal dislocations indicating internal dislocation slip phenomenon is less and more favorable for processing.

Influence of Ultrasonication Treatment on Mechanical, Optical, and Physiochemical Properties of Polyvinyl-alcohol/cornstarch Biocomposite Thin Films

Over the past few decades, Polyvinyl-alcohol (PVOH)/cornstarch (CS)-based composite thin films have garnered significant interest due to their enhanced properties. Synthesis of such films relies heavily on depolymerization reactions within the solution of the PVOH/CS blends. Understanding how depolymerization affects the crystal structure and properties of these films is crucial for further improvement. This study aims to evaluate the depolymerization effects of crosslinked PVOH incorporated with CS as filler materials (with an 80:20 mass ratio) using ultrasonication at various time intervals while maintaining a constant frequency of 25 KHz. The prepared solution is then cast into thin films using blade coating. Comparative analyses were then conducted between samples subjected to ultrasonication (treated) and without ultrasonication (untreated) to assess their properties based on structural physical, mechanical, optical, and aspects of biodegradability . The investigation revealed significant changes in crystal structure and lattice strains following ultrasonication of the PVOH/CS solution when compared to untreated PVOH/CS samples. Importantly, longer ultrasonication times correlated with increased tensile strength. Additionally, the treated samples led to improvements in thin film transparency and a notable decrease in absorbance. These changes were attributed to the mechanical depolymerization induced by ultrasonication, aligning the thin films with the necessary properties for food packaging applications.

Impact of triisopropanolamine on surface composition, crystallographic variation, and thermal behavior of C3A polymorphs

In this study, the impact of triisopropanolamine (TIPA) on both the crystallographic and surface properties of cubic and orthorhombic tricalcium aluminate (C3A) were investigated together with their hydration behavior and strength development. When TIPA was added during the grinding process, the pre-hydration and carbonation of C3A were effectively prevented, and crystal structural changes of C3A were confirmed. It leads to altering the hydration mechanism of C3A phases: in the case of cubic C3A, it promotes the formation of Al-hydrogarnet phases instead of OH-AFm phases even on the first day of curing. Similar hydration behavior was observed with orthorhombic C3A, but the phase transition of OH-AFm phases to Al-hydrogarnet occurs during a specific time period in 1–3 days. The latter was revealed as a very interesting endothermic reaction which can be the only heat absorptive behavior in complex cement hydration as reported so far.

Study on Properties of Micro-Nano Magnetic Composite Prepared by Mechanochemical Method of NdFeB Secondary Waste and Removal of As (V) from Mine Water

The secondary waste produced by NdFeB waste after rare earth recycling, with an annual output of more than tens of thousands of tons, is the largest solid waste emission source in the rare earth industry, and long-term storage causes land resource occupation and environmental pollution. Arsenic-containing mine wastewater has serious harm, wide distribution, and long duration of pollution. In this study, the mechanical ball milling method was used to activate NdFeB secondary waste to prepare micro-nano magnetic composite materials, the main components of which are Fe2O3, Fe3O4, and C. Under mechanical mechanochemical action, the particles are more dispersed, the particle size decreases, the specific surface area increases significantly, the crystal structure changes to amorphous structure, the degree of amorphous shape increases, and the content of Fe-OH increases. Applied to the treatment of As (V) in simulated mine water, it was found that the removal of As (V) by this material was mainly based on chemisorption and monolayer adsorption, and the maximum adsorption amount reached 10.477 mg/g. Zeta, FT-IT, and XPS characterization confirmed that the removal of As (V) was a coordination exchange reaction between the material and As (V) to form an inner sphere complex. The removal rate of As (V) decreased from 94.33% to 73.56% when the initial concentration of solution was 10 mg/L, pH value was 3.0, and material dosage was 1 g/L after 5 times of regrowth. This study provides a new way for the application of NdFeB secondary waste, which has low cost, green environmental protection, and wide application prospects.

Effect of doping TiO2 with Fe on the loading of a natural extract

This study explores the relationship between Fe doping in TiO2 nanoparticles and their capacity to load a natural citrus extract. Synthesized TiO2 (T) and TiO2-Fe (TF) nanoparticles were characterized using XRD patterns, N2 physisorption, UV–Vis and FTIR spectroscopy, and electron microscopy. Fe doping induced shifts in X-ray diffraction patterns and broadened absorption bands in UV–Vis spectra, reflecting changes in crystal structure and electronic transitions. BET analysis revealed increased surface area with Fe doping. Loading of the natural citrus extract was confirmed by FTIR. SEM and TEM images displayed slight morphological changes and a reduced nanoparticle size after Fe doping. Finally, Fe doped TiO2 demonstrated an improvement in loading ability with loading values up to 82.4%.

An exploration of anomalous electrical noise in shocked cyclotrimethylenetrinitramine (RDX)-based explosives

Gas gun shock experiments on cyclotrimethylenetrinitramine (RDX)-based explosive compositions that employ embedded gauge particle velocity tracers have noted a significant amount of electrical noise when compared to other explosive formulations. This paper reexamines previously published embedded gauge data on Cyclotols (60–80 wt. % RDX) to quantify the electromagnetic behavior of these materials. The primary observation is a fourfold increase in the electrical noise when Cyclotols are shocked above 4.22 ± 0.08 GPa. Electromagnetic gauge noise is also observed within particle velocity traces in reactive growth and off-Hugoniot shocks, although at higher pressures than the direct shock case, suggesting a temperature- or kinetically dependent transition. In all cases, the electrical noise disappears upon detonation. By comparing with the static high-pressure phase diagram of RDX, we interpret this change in electromagnetic behavior to be a change in the RDX crystal structure to a piezoelectric phase, although it is uncertain whether the γ or ε phase is responsible for the observed behavior.

Solar-photocatalytic treatment of industrial wastewater using mechanically doped CNS-TiO2 and synergistic TiO2 incorporation: A promising cost-effective approach for industrial wastewater treatment

TiO2 alone demonstrated limited efficiency in degrading industrial wastewater. This study aims to the effectiveness of CNS-doped TiO2 nanoparticles for the degradation of anionic dyes, cationic dyes, and industrial wastewater. For the first time, mechanical milling is employed to synthesize CNS-doped TiO2 nanoparticles using thiourea as a precursor. This results in lattice strains and concomitant crystal and electronic structure changes. We note that these lead to increased photocatalytic activity. Mechanical milling creates a new phase known as brookite, which further improves photocatalytic efficiency through synergistic effects. The physicochemical properties and photocatalytic performance of CNS-TiO2 are evaluated and compared with mspd-TiO2 and commercially available Degussa P-25 TiO2. In photocatalytic degradation tests, remarkably, CNS-TiO2 exhibited beter degradation efficiency for anionic dyes (MO - 65 ± 3 % in 120 min; CR - 100 % in 30 min), cationic dyes (MB - 100 % in 30 min; Rh B 100 % in 120 min) and industrial wastewater (∼100 % in 120 min). The treated wastewater TDS (56 ± 2 ppm), TSS (0.16 g/L), CHNS, and COD (190 ± 10 mg/L) results are closer to drinking water quality. The reusability test revealed lower activity in the mspd-TiO2 and CNS-TiO2 attributed to particle aggregation, the loss of activation sites, and mass loss. This study demonstrates CNS-TiO2 enhanced photocatalytic properties and cost-effectiveness making them highly promising for treating any industrial effluents containing dyes.

A new crystal form of Hx2TNBI·2H2O through solvent-induced crystallization

Polymorphism is universal in energetic materials (EMs), which is originated from the differences of molecular conformers and stacking mode. The polymorphic transition may lead to the change of crystal structure and properties of EMs. In this work, β-Hx2TNBI·2H2O (β-1) was successfully synthesized through solvent-induced conformational transition of Hx2TNBI·2H2O. From the perspective of quantum chemistry and molecular dynamics, the crystal stacking changes caused by different molecular conformations are discussed in detail, which leads to the properties difference of EMs. The results show that β-1 featured wave-like crystal stacking, making it less sensitive to external mechanical stimuli than α-Hx2TNBI·2H2O (α-1) (α-1: IS > 6 J, FS > 288 N; β-1: IS > 20 J, FS > 360 N). α-1 featured better the aromaticity, which gives it higher thermal stability than β-1 (α-1: Td = 186 °C; β-1: Td = 146 °C). Simultaneously, compared with β-1, α-1 has higher crystal density and detonation performance. This work provides a new and effective way to change the safety of EMs.

Dual substitution of host lattice ions to enhance the luminescence properties of Zn2TiO4:Cr3+ phosphor.

Near-infrared light sources have potential applications in many fields. Cr3+ is a good luminescence centre to prepare near-infrared phosphors. Improving the performance of existing near-infrared luminescent materials has indeed attracted great interest from researchers. The luminescence properties of Zn2TiO4:Cr3+ were improved by crystal field engineering strategies. Zn2+-Ti4+ was partially replaced using a Li+-Nb5+ ion pair based on the Zn2TiO4:Cr3+ phosphors. Luminescence Cr3+-activated luminescent materials are sensitive to changes in the local crystal structure and crystal field environment. Doping of Li+-Nb5+ increased the luminescence intensity up to 2.7 times that of the undoped sample. Also, the thermal stability of the phosphor was greatly increased by the replacement of Li+-Nb5+.

Changes in enamel hardness, wear resistance, surface texture, and surface crystal structure with glass ionomer cement containing BioUnion fillers.

This study investigated the potential of BioUnion filler containing glass ionomer cement (GIC) to enhance the properties of enamel surrounding restorations, with a specific focus on the effect on hardness. The hardness of the bovine enamel immersed in the cement was measured using Vickers hardness numbers. Following sliding and impact wear simulations, the enamel facets were examined using confocal-laser-scanning microscopy and scanning-electron microscopy. Surface properties were further analyzed using energy-dispersive X-ray spectroscopy and X-ray diffraction (XRD). A significant increase in Vickers hardness numbers was observed in the BioUnion filler GIC after 2 days. Furthermore, the mean depth of enamel facets treated with BioUnion filler GIC was significantly less than that of untreated facets. Characteristic XRD peaks indicating the presence of hydroxyapatite were also observed. Our findings imply that GIC with BioUnion fillers enhances the mechanical properties of the tooth surface adjacent to the cement.

Microstructure evolution from silicon core to surface in electronic-grade polycrystalline silicon

Large-size electronic-grade polycrystalline silicon is an important material in the semiconductor industry with broad application prospects. However, electronic-grade polycrystalline silicon has extremely high requirements for production technology and currently faces challenges such as carbon impurity breakdown, microstructure and composition nonuniformity and a lack of methods for preparing large-size mirror-like polycrystalline silicon samples. This paper innovatively uses physical methods such as wire cutting, mechanical grinding and ion thinning polishing to prepare large-size polycrystalline silicon samples that are clean, smooth, free from wear and have clear crystal defects. The material was characterized at both macroscopic and microscopic levels using metallographic microscopy, scanning electron microscopy (SEM) with backscattered electron diffraction (EBSD) techniques and scanning transmission electron microscopy (STEM). The crystal structure changes from single crystal silicon core to the surface of the bulk in the large-size polycrystalline silicon samples were revealed, providing a technical basis for optimizing and improving production processes.

Phase evolution, defect chemistry, and electrical properties of Na0.5Bi0.5TiO3-BiNi0.5Ti0.5O3 solid solutions

Solid solutions of Na0.5Bi0.5TiO3 (NBT) and BiNi0.5Ti0.5O3 (BNiT) were prepared by a solid-state reaction route, and their electrical properties investigated by a combination of impedance spectroscopy and electromotive force measurements to explore the possibility of developing mixed ionic-electronic conductors based on NBT. Phase analysis showed that BNiT has a large solid solution limit in NBT (60 mol% based on X-ray diffraction), and the room temperature crystal structure changes from rhombohedral to pseudo-cubic with increasing BNiT content. Neutron diffraction revealed the coexistence of rhombohedral and tetragonal phases when the BNiT content ≥ 40 mol%. Electrically, incorporation of BNiT induces p-type electronic conduction into NBT by hopping of holes between Ni2+ (NiNix) and Ni3+ (NiNi·), and therefore changes the electrical conduction mechanism systematically from predominant oxide-ion conduction to mixed ionic-electronic conduction and then to predominant p-type electronic conduction. The total conductivity of the solid solutions showed a “V-shape” variation with increasing BNiT content. Possible mechanisms for the phase evolution and the conductivity-composition relationships are discussed. Achieving high levels of ionic and electronic conductivity simultaneously in NBT by introducing elements with variable oxidation states remains challenging due to the competition between an enhanced electronic component and a suppressed ionic component. Low levels of BNiT incorporation are, however, beneficial to reducing the dielectric loss of NBT for dielectric applications.

Accelerating photoelectrochemical CO2RR selectively of C2+ products by integrating Ag/Pd cocatalysts on Cu/Cu2O/CuO heterojunction nanorods

The Cu-based photoelectrochemical CO2 reduction reaction (PEC–CO2RR) represents a convenient approach for producing value-added C2+ products, aiming to achieve carbon neutrality by reducing greenhouse gas emissions. However, these reactions typically suffer from limited selectivity. In this work, we fabricate Cu/Cu2O/CuO nanorod (CuR)-based heterojunction architectures integrated with Ag and Pd cocatalysts to boost the selectivity of C2+ products. The proposed Cu/Cu2O/CuO/Ag-Pd (CuR/Ag-Pd) photoelectrodes are used as photocathodes to generate a maximum Faradaic efficiency (FE) of C2+ products exceeding 53% by suppressing the hydrogen evolution reaction (HER). The FE improvement is approximately 22-fold (n-propanol), 12-fold (ethanol), 13-fold (acetaldehyde), and 6-fold (acetate) compared with CuR photoelectrodes operating at a negative applied potential of −1.8 V (vs. reversible hydrogen electrode, RHE). Conversely, the CuR photoelectrodes exhibit a maximum HER rate of ∼86% at −1.8 V (vs. RHE), higher than those of the CuR/Ag (54%) and CuR/Ag-Pd (35%) photoelectrodes. The superior PEC–CO2RR performance of CuR/Ag-Pd photoelectrodes is attributable to the higher electrochemical active surface area (6.7 mF/cm2) and faster charge transfer rate at the electrode/electrolyte interface owing to the presence of cocatalysts. In addition, the CuR/Ag-Pd photoelectrodes exhibit remarkable long-term stability retaining 70% of the initial performance even after a relatively more negative applied potential at −1.2 V. A comprehensive investigation into the changes in surface morphology, crystal structure, and elemental composition after PEC–CO2RR confirms the higher stability of CuR/Ag-Pd photoelectrodes. Thus, this work provides novel perceptions into the development of Cu-based heterojunction photoelectrodes integrated with Ag/Pd cocatalysts for improving the selectivity of C2+ products.

Symmetry Breaking and Ascending in the Magnetic Kagome Metal FeGe

Spontaneous symmetry breaking—the phenomenon in which an infinitesimal perturbation can cause the system to break the underlying symmetry—is a cornerstone concept in the understanding of interacting solid-state systems. In a typical series of temperature-driven phase transitions, higher-temperature phases are more symmetric due to the stabilizing effect of entropy that becomes dominant as the temperature is increased. However, the opposite is rare but possible when there are multiple degrees of freedom in the system. Here, we present such an example of a symmetry-ascending phenomenon upon cooling in a magnetic kagome metal FeGe by utilizing neutron Larmor diffraction and Raman spectroscopy. FeGe has a kagome lattice structure with simple A-type antiferromagnetic order below Néel temperature TN≈400 K and a charge density wave (CDW) transition at TCDW≈110 K, followed by a spin-canting transition at around 60 K. In the paramagnetic state at 460 K, we confirm that the crystal structure is indeed a hexagonal kagome lattice. On cooling to around TN, the crystal structure changes from hexagonal to monoclinic with in-plane lattice distortions on the order of 10−4 and the associated splitting of the double-degenerate phonon mode of the pristine kagome lattice. Upon further cooling to TCDW, the kagome lattice shows a small negative thermal expansion, and the crystal structure gradually becomes more symmetric upon further cooling. A tendency of increasing the crystalline symmetry upon cooling is unusual; it originates from an extremely weak structural instability that coexists and competes with the CDW and magnetic orders. These observations are against the expectations for a simple model with a single order parameter and hence can only be explained by a Landau free energy expansion that takes into account multiple lattice, charge, and spin degrees of freedom. Thus, the determination of the crystalline lattice symmetry as well as the unusual spin-lattice coupling is a first step towards understanding the rich electronic and magnetic properties of the system, and it sheds new light on intertwined orders where the lattice degree of freedom is no longer dominant. Published by the American Physical Society 2024

Detection of ammonia mercerization in cotton textiles

AbstractCotton textiles are mercerized with anhydrous ammonia liquefied at ca. − 33 °C to improve their mechanical performance, appearance, and handle. Similar effects may also be achieved with NaOH mercerization, but goods mercerized with liquid ammonia (L-NH3) are judged qualitatively better (e.g., softer hand) and thus command a greater price. Therefore, it is of interest to be able to test and confirm whether cotton textiles labeled as L-NH3 treated are indeed so. Building on previous work, we report on tests in collaboration with a process house on identifying ammonia-mercerized fabrics from a pool of cotton textiles treated with L-NH3, NaOH, neither, or both––using FTIR-ATR spectroscopy. It is based on detecting the change in crystal lattice structure from type I (native cellulose) to type II (after NaOH mercerization) or type III (after ammonia mercerization). We could consistently differentiate the ammonia-mercerized fabrics from the untreated and those mercerized with NaOH, but the latter could not be differentiated from fabrics mercerized with both. It was also possible to detect evidence of ammonia mercerization in 4- and 14-year-old samples. Graphical abstract

Improving performance of cathode NMC-811 by CeO2-coating for Li-ion battery

The high energy density layered oxide LiNi0.8Mn0.1Co0.1O2 (NMC811) holds great promise as a cathode material for future Li-ion batteries. However, its application in electric vehicles is hindered by issues such as inadequate cycle performance and rate capability. Additionally, the corrosion caused by the electrolyte poses limitations on high voltage operation. In this study, Cerium Oxide (CeO2) was used to coat NMC811 using wet chemical method followed by heat treatment. Distilled water was used to dissolve Ce salt instead of ethanol so that it can reduce coating costs and is more environmentally friendly. XRD analysis showed no significant change in the hexagonal crystal structure of NMC811 material but the appearance of small CeO2 peaks in patterns. Electrochemical test of CeO2 coated NMC811 exhibited 18% and 9% higher cyclic and rate performance, respectively in comparison to pristine material.

Crystal-Structure Control of Molecular Semiconductors by Methylthiolation: Toward Ultrahigh Mobility.

ConspectusThe crystal structure of organic semiconductors has been regarded as one of the crucial factors for realizing high-performance electronic devices, such as organic field-effect transistors. However, although the control of crystal structures of organic semiconductors has been examined in the last two decades of intensive efforts of the development of organic semiconductors, active measures to control crystal structures enabling high carrier mobility are still limited. In 2016, our research group noticed that regioselective methylthiolation could provide a selective crystal structure change from an ordinary herringbone structure to a pitched π-stacking structure, similar to the crystal structure of rubrene, in the benzo[1,2-b:4,5-b']dithiophene (BDT) system. Following this serendipitous finding, our group systematically investigated the relationship between the molecular and crystal structures of a range of methylthiolated aromatic and heteroaromatic compounds.This Account provides a comprehensive overview of our research efforts and advancements in the development of methylthiolated small-molecule-based organic semiconductors (molecular semiconductors). We first describe the outline of the past development of molecular semiconductors, focusing on the types of crystal structures of high-performance molecular semiconductors. Then, we describe our findings on the drastic crystal structure change in the BDT system upon methylthiolation, detailing the causes of the change in terms of the intermolecular contacts and intermolecular interaction energies. This is followed by the confirmation of the generality of the crystal-structure change by methylthiolation of a series of acene and heteroacenes, where the herringbone structure in the parent system is unexceptionally transformed into the pitched π-stacking structure, a promising crystal structure for high-mobility molecular semiconductors well exemplified by the prototypical molecular semiconductor, rubrene. In fact, the methylthiolated anthradithiophene afforded comparable high mobility to rubrene in single-crystal field-effect transistors. Then, we demonstrate that the sandwich herringbone structures of peri-condensed polycyclic aromatic hydrocarbons, including pyrene, perylene, and peropyrene, change into brickwork crystal structures upon methylthiolation and that, among these compounds, very promising molecular semiconductors, methylthiolated pyrene and peropyrene, showing ultrahigh mobility of 30 cm2 V s-1, are realized.Through the studies, by gaining insights into the underlying mechanisms driving the crystal structure changes, we lay a strong foundation for tackling challenges related to controlling the crystal structures and developing high-performance molecular semiconductors. This will be a distinct approach from the past activities in the development of molecular semiconductors that mainly focused on molecules themselves, including their synthesis, properties, and characterization. We thus anticipate that our findings and the present Account will open the door to a new era of the development of molecular semiconductors.

Study on high voltage (5 V) spinel lithium manganese oxide LiNi0.5Mn1.5O4 by doping niobium

AbstractThe effect of niobium ions with high‐valence doping on high‐voltage LiNi0.5Mn1.5O4 (LNMO) materials was investigated. LiNi0.5Mn1.5−xNbxO4 was prepared by doping high‐valent niobium ions into LiNi0.5Mn1.5O4 material using the organic assisted combustion method. The experimental samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), electrochemical impedance (EI), and cyclic voltammetry (CV) analysis. The experimental results show that ‐doping with high‐valence niobium ions changes the orientation of the crystal plane growth of spinel particles, and the morphology of these particles changes from the octahedral shape before doping to the spherical shape after doping. With the increase in doping amount, the crystal structure changes gradually, resulting in the Li0.96Nb1.01O3 impurity phase. The doping of high valence‐niobium ions increases the content of Mn3+ in the material, resulting in the appearance of a 4 V discharge platform and the formation of a 4.7 and 4 V discharge platforms. The doping of Nb can improve the cycling stability of LiNi0.5Mn1.5O4 material, but the specific capacity of the material is reduced.