Accuracy of edentulous full-arch implant impression: An in vitro comparison between conventional impression, intraoral scan with and without splinting, and photogrammetry.

OBJECTIVES: The purpose of this in vitro study was to compare the trueness and precision of complete arch implant impressions using conventional impression, intraoral scanning with and without splinting, and stereophotogrammetry. MATERIALS AND METHODS: An edentulous model with six implants was used in this study. Four implant impression techniques were compared: the conventional impression (CI), intraoral scanning (IOS) without splinting, intraoral scanning with splinting (MIOS), and stereophotogrammetry (SPG). An industrial blue light scanner was used to generate the baseline scan from the model. The CI was captured with a laboratory scanner. The reference best-fit method was then applied in the computer-aided design (CAD) software to compute the three-dimensional, angular, and linear discrepancies among the four impression techniques. The root mean square (RMS) 3D discrepancies in trueness and precision between the four impression groups were analyzed with a Kruskal-Wallis test. Trueness and precision between single analogs were assessed using generalized estimating equations. RESULTS: Significant differences in the overall trueness (p = .017) and precision (p < .001) were observed across four impression groups. The SPG group exhibited significantly smaller RMS 3D deviations than the CI, IOS, and MIOS groups (p < .05), with no significant difference detected among the latter three groups (p > .05). CONCLUSIONS: Stereophotogrammetry showed superior trueness and precision, meeting misfit thresholds for implant-supported complete arch prostheses. Intraoral scanning, while accurate like conventional impressions, exhibited cross-arch angular and linear deviations. Adding a splint to the scan body did not improve intraoral scanning accuracy.

Combined Metabolite and Transcriptomic Profiling Unveil a Potential Gene Network Involved in the Triterpenoid Metabolism of Rose roxburghii.

Rose roxburghii, a horticulturally significant species within the Rosa genus of the Rosaceae family, is renowned for its abundance of secondary metabolites and ascorbate, earning it the title 'king of vitamin C'. Despite this recognition, the mechanisms underlying the biosynthesis and regulation of triterpenoid compounds in R. roxburghii remain largely unresolved. In this study, we conducted high-performance liquid chromatography profiling across various organs of R. roxburghii, including fruit, root, stem, and leaves, revealing distinct distributions of triterpenoid compounds among different plant parts. Notably, the fruit exhibited the highest total triterpenoid content, followed by root and stem, with leaf containing the lowest levels, with leaf containing the lowest levels. Transcriptomic analysis unveiled preferential expression of members from the cytochrome P450 (CYP) and glycosyltransferase (UGT) families, likely contributing to the higher accumulation of both ascorbate and triterpenoid compounds in the fruits of R. roxburghii compared to other tissues of R. roxburghii. Transcriptomic analysis unveiled a potential gene network implicated in the biosynthesis of both ascorbate and triterpenoid compounds in R. roxburghii. These findings not only deepen our understanding of the metabolic pathways in this species but also have implications for the design of functional foods enriched with ascorbate and triterpenoids in R. roxburghii.

Efficacy of surgical methods for peri-implantitis: a systematic review and network meta-analysis.

BACKGROUND: Peri-implantitis is the most difficult biological complication associated with dental implants, often requiring surgical treatments in advanced stages. This study compares the effectiveness of different surgical methods for peri-implantitis. METHODS: Randomized controlled trials (RCTs) of different surgical treatments for peri-implantitis were extracted from EMBASE, Web of Science, Cochrane Library databases, and PubMed systematically. Pairwise comparisons and network meta-analyses (NMA) were conducted to analyze the effect of surgical treatments on probing depth (PD), radiographic bone fill (RBF), mucosal recession (MR), bleeding on probing (BOP), and clinical attachment level (CAL). In addition, risk of bias, quality of evidence, and statistical heterogeneity of the selected studies were evaluated. A total of 13 articles were included in this study, involving open flap debridement (OFD), resective therapy (RT), and augmentative therapy (AT) with and without adjunctive treatments (laser therapy, photodynamic therapy, local antibiotics, phosphoric acid, and ozone therapy). RESULTS: AT improved RBF and CAL more than OFD, but does not outperform OFD in reducing peri-implant soft-tissue inflammation. AT, OFD and RT did not significantly alter the levels of MR. Addition of ozone therapy improved the effect of AT, but addition of photodynamic therapy did not affect PD reduction and CAL gain significantly. Similarly, adjuvant treatment with phosphoric acid during RT did not significantly change the outcome of BOP. CONCLUSIONS: Within the limitation of this systematic review and NMA, AT was superior to OFD in improving peri-implantitis outcomes. While adjunct use of ozone therapy may further improve the efficacy of AT, the limited evidence supporting this combination therapy argues for cautionary interpretation of these results.

A template-free assembly of Cu,N-codoped hollow carbon nanospheres as low-cost and highly efficient peroxidase nanozymes.

Developing carbon-based materials with high catalytic performance and sensitivity has significance in low-cost and highly efficient nanozymes. Herein, for the first time, Cu,N-codoped hollow carbon nanospheres (CuNHCNs) with highly active Cu-Nx sites were successfully assembled through a template-free strategy, in which Cu2+-poly(m-phenylenediamine) (Cu-PmPD) nanospheres were utilized as the source of Cu, N and C. Benefiting from the synergistic effect of the hollow spherical structure and optimized composition, the CuNHCN exhibits high affinity for 3,3',5,5'-tetramethylbenzidine and H2O2 with 0.0655 mM and 0.918 mM, respectively, which are superior to those of HRP and most metal-based nanozymes. Moreover, by employing glucose and ascorbic acid (AA) as biomolecule models, a CuNHCN-based colorimetric detection platform is developed. The CuNHCN exhibits superior peroxidase mimicking activity and sensitivity in detecting glucose and AA with a detection limit of 0.187 µM and 68.9 nM (S/N = 3), respectively. Also, the colorimetric detection based on the CuNHCN towards glucose and AA in human serum presents superior practicability and accuracy. The assay provides a new avenue for designing and fabricating low-cost peroxidase nanozymes with high performance in bioassays.

Antifungal Activity and Biological Characteristics of the Novel Fungicide Quinofumelin Against Sclerotinia sclerotiorum.

Sclerotinia sclerotiorum is a devastating plant pathogen with a broad host range and worldwide distribution. The application of chemical fungicides is a primary strategy for controlling this pathogen. However, under the high selective pressure of chemical fungicides, fungicide resistance has emerged and gradually increased, resulting in the failure to control S. sclerotiorum in the field. Quinofumelin is a novel quinoline fungicide, but its antifungal activities against plant pathogens have been rarely reported. Here, we determined the antifungal activity of quinofumelin against S. sclerotiorum in vitro and in planta. The median effect concentration (EC50) values ranged from 0.0004 to 0.0059 µg ml-1 with a mean EC50 of 0.0017 ± 0.0009 µg ml-1 and were normally distributed (P = 0.402). In addition, no cross resistance was observed between quinofumelin and other fungicides, dimethachlone, boscalid, or carbendazim, which are commonly used to manage S. sclerotiorum. Quinofumelin did not affect glycerol and oxalic acid production of either carbendazim-sensitive or -resistant isolates. Moreover, quinofumelin exhibited excellent protective, curative, and translaminar activity against S. sclerotiorum on oilseed rape leaves. Protective activity was higher than curative activity. Interestingly, quinofumelin inhibited the formation of the infection cushion in S. sclerotiorum, which may contribute to the control efficacy of quinofumelin against S. sclerotiorum in the field. Our findings indicate that quinofumelin has excellent control efficacy against S. sclerotiorum in vitro and in planta as compared with extensively used fungicides and could be used to manage carbendazim- and dimethachlone-resistance in S. sclerotiorum in the field.

Phase Control on Surface for the Stabilization of High Energy Cathode Materials of Lithium Ion Batteries.

The development of high energy electrode materials for lithium ion batteries is challenged by their inherent instabilities, which become more aggravated as the energy densities continue to climb, accordingly causing increasing concerns on battery safety and reliability. Here, taking the high voltage cathode of LiNi0.5Mn1.5O4 as an example, we demonstrate a protocol to stabilize this cathode through a systematic phase modulating on its particle surface. We are able to transfer the spinel surface into a 30 nm shell composed of two functional phases including a rock-salt one and a layered one. The former is electrochemically inert for surface stabilization while the latter is designated to provide necessary electrochemical activity. The precise synthesis control enables us to tune the ratio of these two phases, and achieve an optimized balance between improved stability against structural degradation without sacrificing its capacity. This study highlights the critical importance of well-tailored surface phase property for the cathode stabilization of high energy lithium ion batteries.

Activity of Demethylation Inhibitor Fungicide Metconazole on Chinese Fusarium graminearum Species Complex and Its Application in Carbendazim-Resistance Management of Fusarium Head Blight in Wheat.

Fusarium graminearum species complex (FGSC), causing Fusarium head blight (FHB) of wheat, has species-specific geographical distributions in wheat-growing regions. In recent years, benzimidazole resistance of FHB pathogens has been largely widespread in China. Although the demethylation inhibitor fungicide metconazole has been used for FHB control in some countries, no information about metconazole sensitivity of Chinese FHB pathogen populations and efficacy of metconazole in FHB control in China is available. In this study, the sensitivity of FGSC to metconazole was measured with 32 carbendazim-sensitive strains and 35 carbendazim-resistant strains based on mycelial growth. The 50% effective concentration values of 67 strains were normally distributed and ranged from 0.0209 to 0.0838 µg ml-1, with a mean of 0.0481 ± 0.0134 µg ml-1. No significant difference in metconazole sensitivity was observed between carbendazim-sensitive and -resistant populations. An interactive effect of metconazole and phenamacril, a novel cyanoacrilate fungicide approved in China against Fusarium spp., in inhibiting mycelial growth showed an additive interaction at different ratios. Furthermore, field trials to evaluate the effect of metconazole and metconazole + phenamacril treatments in FHB control, deoxynivalenol (DON) production, and grain yields were performed. Compared with the fungicides carbendazim and phenamacril currently used in China, metconazole exhibits a better efficacy for FHB control, DON production, and grain yields, and dramatically reduces use dosages of chemical compounds in the field. The mixture of metconazole and phenamacril at ratios of 2:3 and 1:2 showed the greatest efficacy for FHB control, DON production, and grain yields among all the fungicide treatments but its use dosages were higher in comparison with metconazole alone. In addition, FHB control, grain yields, and DON levels were significantly correlated with each other, showing that visual disease indices can be used as an indicator of grain yields and DON contamination. Meanwhile, the frequency of carbendazim-resistant alleles in F. graminearum populations was dramatically reduced after metconazole and phenamacril alone and the mixture of metconazole and phenamacril applications, indicating that metconazole and a mixture of metconazole and phenamacril can be used for carbendazim resistance management of FHB in wheat. Overall, the findings of this study provide important data for resistance management of FHB and reducing DON contamination in wheat grains.

[The effect of EDARV370A on facial and ear morphologies in Uyghur population].

The ectodysplasinA receptor gene (EDAR) plays an important role in the development of ectoderm. The derived G allele of its key missense variant EDARV370A is prevalent in East Asians and Americans, but rare in Africans and Europeans. This leads to distinct ectodermal-derived phenotypes between different continental groups, such as the straighter and thicker hair, more eccrine sweat glands, feminine smaller breasts, shovel incisors characteristic of East Asians. At present, we know little about the association between EDARV370A and facial and ear morphology characteristics. To better understand the effect of EDARV370A on craniofacial phenotypes, we systematically examined the association between EDARV370A and 136 facial quantitative phenotypes, one chin ordinal phenotype and six ear ordinal phenotypes in 715 Uyghurs. The quantitative phenotypes were derived by applying our automated landmark annotation method to facial 3D photos and the ordinal phenotypes were manually graded from facial 2D photos. The analysis identified significant association (P<0.05 after multiple testing correction) between EDARV370A and eight facial phenotypes, one chin phenotype and three ear morphology phenotypes. Our study thus elucidated the pleotropic effect of EDARV370A on craniofacial phenotypes in a European-Asian admixed Uyghur population.

Vasculature Characterization of a Multiterritory Perforator Flap: An Experimental Study.

Background Tip necrosis in the perforator flap is a significant problem in clinical practice. This study aimed to characterize the vasculature of a multiterritory perforator flap using a rat model and to investigate the impact of the vasculature on flap survival. Methods In total, 105 Sprague Dawley rats were divided into seven groups, including the control, 3 hours postoperative (PO), 12 hours PO, 1 day PO, 3 days PO, 5 days PO, and 7 days PO. A perforator flap with three territories based on the deep iliac circumflex artery was performed. Flaps with only skin incisions and vessel exposure were performed in the control group. The first choke zone (FCZ) was located between the anatomical and dynamic territories, and the second choke zone (SCZ) was located between the dynamic and potential territories. Sodium fluorescein and lead oxide-gelatin angiography and histological examination were performed in each group. Results Sodium fluorescein angiography revealed delayed staining in the perforator flap PO, particularly in the FCZ and SCZ. The delay phenomenon disappeared after 12 hours PO in the FCZ and after 1 day PO in the SCZ. Nonfluorescein-stained areas were found distal to the potential territory. In the FCZ PO, the choke vessels were dilated, while the number of microvessels was increased in the SCZ without choke vessel dilation. Conclusions The remodeling of choke vessels and increase in microvessel number represent arteriogenesis and angiogenesis, respectively. This neovascularization was responsible for flap survival in the entire dynamic territory and part of the potential territory.

The Effect of Inducible Nitric Oxide Synthase on Multiterritory Perforator Flap Survival in Rats.

Background Inducible nitric oxide synthase (iNOS) plays an important role in vasodilation, angiogenesis, and ischemia-reperfusion injury. We investigated the effects of iNOS on the survival and choke vessels of multiterritory perforator flaps in rats. Methods In this study, 84 rats were divided into two groups of 42 rats each and subjected to multiterritory perforator flap operations. Rats in group A received daily intraperitoneal doses of 100 mg per kg of aminoguanidine (AG) and rats in group B received daily intraperitoneal injections of the same volume of saline solution. On postoperative day 7, the surviving flap area was calculated as a percentage of the total flap dimensions using DP2-BSW software. The diameter and density of microvessels in the second choke zone of the flap were calculated from histology studies. The nitric oxide (NO) content was measured using NO concentration assay kits, and the levels of vascular endothelial growth factor (VEGF) and iNOS were assessed using western blotting. Superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were measured using test kits. Laser Doppler imaging was used to evaluate flap perfusion in the second choke zone for 7 days after surgery. Results The flap survival area, diameter and density of microvessels, iNOS and VEGF levels, NO content, blood perfusion, and MDA content were significantly higher in the control group compared with the AG group, whereas SOD activity was significantly lower in the control group. Conclusions iNOS has a beneficial effect on the survival of multiterritory perforator flaps.

Two lanthanum(III) complexes containing η2-pyrazolate and η2-1,2,4-triazolate ligands: intramolecular C-H...N/O interactions and coordination geometries.

The lanthanum(III) complexes tris(3,5-diphenylpyrazolato-κ(2)N,N')tris(tetrahydrofuran-κO)lanthanum(III) tetrahydrofuran monosolvate, [La(C(15)H(11)N(2))(3)(C(4)H(8)O)(3)]·C(4)H(8)O, (I), and tris(3,5-diphenyl-1,2,4-triazolato-κ(2)N(1),N(2))tris(tetrahydrofuran-κO)lanthanum(III), [La(C(14)H(10)N(3))(3)(C(4)H(8)O)(3)], (II), both contain La(III) atoms coordinated by three heterocyclic ligands and three tetrahydrofuran ligands, but their coordination geometries differ. Complex (I) has a mer-distorted octahedral geometry, while complex (II) has a fac-distorted configuration. The difference in the coordination geometries and the existence of asymmetric La-N bonding in the two complexes is associated with intramolecular C-H...N/O interactions between the ligands.

Titanium surfaces with biomimetic topography and copper incorporation to modulate behaviors of stem cells and oral bacteria.

Purpose: Insufficient osseointegration and implant-associated infection are major factors in the failure of Ti-based implants, thus spurring scientists to develop multifunctional coatings that are better suited for clinical requirements. Here, a new biomimetic micro/nanoscale topography coating combined with antibacterial copper was simultaneously designed for Ti-based implant surfaces by adopting a hybrid approach combining plasma electrolytic oxidation and hydrothermal treatment. Results: The biological interactions between this biofunctionalized material interface and stem cells promoted cellular adhesion and spreading during initial attachment and supported cellular proliferation for favorable biocompatibility. Bone marrow mesenchymal stem cells (BMMSCs) on the coating displayed enhanced cellular mineral deposition ability, higher alkaline phosphatase activity, and upregulated expression of osteogenic-related markers without the addition of osteoinductive chemical factors, which improved osseointegration. More interestingly, this new coating reduced the viability of oral pathogens (Fusobacterium nucleatum and Porphyromonas gingivalis)-the primary causes of implant-associated infections as indicated by damage of cellular structures and decreased population. This is the first study investigating the antibacterial property of dental implants modified by a hybrid approach against oral pathogens to better mimic the oral environment. Conclusion: These findings suggest that biofunctionalization of the implant coating by surface modification methods and the incorporation of antibacterial copper (Cu) offer superior osteogenesis capability and effective antibacterial activity, respectively. These strategies have great value in orthopedic and dental implant applications.

Construction of Li3PO4 nanoshells for the improved electrochemical performance of a Ni-rich cathode material.

A Li3PO4 nanocoating around a nickel-rich cathode material was successfully constructed via controlling the reaction between the electrode material and a preformed phosphorus-containing polymeric nanoshell; this not only effectively tackles the alkali residue challenge, but it also contributes to much-improved electrochemical performance being shown by a high-energy cathode.

Mechanism of Fusarium graminearum Resistance to Ergosterol Biosynthesis Inhibitors: G443S Substitution of the Drug Target FgCYP51A.

Fusarium head blight (FHB), caused by the Fusarium graminearum species complex, is a devastating fungal disease resulting in substantial yield and quality losses. Ergosterol biosynthesis inhibitors (EBIs) are the most popular chemicals for controlling FHB. Recently, the resistance of F. graminearum to EBIs has emerged in the field, and an amino acid substitution (G443S) of the sterol 14α-demethylase FgCYP51A was detected in the field resistant strains. To further illustrate the resistance mechanism of F. graminearum to EBIs, site-directed mutants conferring the G443S substitution of FgCYP51A were generated from the progenitor strain PH-1 via genetic transformation with site-directed mutagenesis. We found that the FgCYP51A-G443S substitution significantly decreased the sensitivity of F. graminearum to EBIs with EC50 values ranging from 0.1190 to 0.2302 µg mL-1 and EC90 values ranging from 1.3420 to 9.1119 µg mL-1 for tebuconazole. Furthermore, the FgCYP51A-G443S substitution decreased sexual reproduction and virulence, which will reduce the initial infection source of pathogen populations in the field, while the increase of sporulation capability may enhance the frequencies of the disease cycle, thereby contributing to epidemics of FHB disease. Surprisingly, the FgCYP51A-G443S substitution accelerated DON biosynthesis by upregulating TRI5 expression and enhancing the fluorescence intensity of TRI1-GFP, the marker protein of Fusarium toxisomes. Thus, we concluded that the FgCYP51A-G443S substitution regulates EBI-fungicide resistance and DON biosynthesis, increasing the risk of fungicide resistance development in the field, thereby threatening the control efficacy of EBIs against FHB.

Bis[µ-N,N'-bis(quinolin-8-yl)pyridine-2,6-dicarboxamido]dizinc(II) dichloromethane disolvate.

The title compound, [Zn(2)(C(25)H(15)N(5)O(2))(2)]·2CH(2)Cl(2), is a dinuclear double-helical complex which lies on a crystallographic twofold axis. In the complex, both ligands are partitioned into two tridentate domains which allow each ligand to bridge both metal centres. Each Zn(II) atom is six-coordinated in a distorted octahedral environment formed by two amide N atoms, two quinoline N atoms and two pyridine N atoms from two different ligand molecules, with the central pyridine ring, unusually, bridging two Zn(II) atoms. The deprotonated ligand is not planar, the amide side chains being considerably twisted out from the plane of the central pyridine ring.

Effect of miRNA-200a on radiosensitivity of osteosarcoma cells by targeting Bone morphogenetic protein receptor 2.

To study the effect of miR-200a on radiosensitivity of osteosarcoma cells and its mechanism. NC (normal cell) group, mimic-NC group, mimic-miR-200a group, inhibitor-NC group, inhibitor-miR-200a group, si-NC group, si-BMPR2 (Bone morphogenetic protein receptor 2) group, mimic-miR-200a+vector-NC group, and mimic-miR-200a+vector-BMPR2 group were set; the cells of the above groups were irradiated with different radiation intensities (0, 1, 2, 3, and 4 Gy). The expression of miR-200a and BMPR2 mRNA was detected by qRT-PCR; the expression of BMPR2 protein was detected by Western blot; cell viability was detected by MMT (3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide); apoptosis rate was detected by flow cytometry. Cell clone formation experiment was used to detect cell radiosensitivity. Dual-luciferase reporter gene test was used to detect cell fluorescence activity. The expression of BMPR2 was high and the expression of miR-200a was low in osteosarcoma tissues after radiotherapy and in osteosarcoma cells after irradiation. Overexpression of miR-200a and interference with BMPR2 expression inhibits osteosarcoma cell proliferation, promotes apoptosis, and increases cellular radiosensitivity, miR-200a targets expression of BMPR2, and overexpression of BMPR2 reverses the radiosensitizing and apoptotic effects of miR-200a expression on osteosarcoma cells. Overexpression of miR-200a inhibits osteosarcoma cell proliferation, promotes apoptosis, and increases cellular radiosensitivity. The mechanism may be related to the regulation of BMPR2, which may provide new targets and new ideas for osteosarcoma treatment.

Mechanism of validamycin A inhibiting DON biosynthesis and synergizing with DMI fungicides against Fusarium graminearum.

Deoxynivalenol (DON) is a vital virulence factor of Fusarium graminearum, which causes Fusarium head blight (FHB). We recently found that validamycin A (VMA), an aminoglycoside antibiotic, can be used to control FHB and inhibit DON contamination, but its molecular mechanism is still unclear. In this study, we found that both neutral and acid trehalase (FgNTH and FgATH) are the targets of VMA in F. graminearum, and the deficiency of FgNTH and FgATH reduces the sensitivity to VMA by 2.12- and 1.79-fold, respectively, indicating that FgNTH is the main target of VMA. We found FgNTH is responsible for vegetative growth, FgATH is critical to sexual reproduction, and both of them play an important role in conidiation and virulence in F. graminearum. We found that FgNTH resided in the cytoplasm, affected the localization of FgATH, and positively regulated DON biosynthesis; however, FgATH resided in vacuole and negatively regulated DON biosynthesis. FgNTH interacted with FgPK (pyruvate kinase), a key enzyme in glycolysis, and the interaction was reduced by VMA; the deficiency of FgNTH affected the localization of FgPK under DON induction condition. Strains with a deficiency of FgNTH were more sensitive to demethylation inhibitor (DMI) fungicides. FgNTH regulated the expression level of FgCYP51A and FgCYP51B by interacting with FgCYP51B. Taken together, VMA inhibits DON biosynthesis by targeting FgNTH and reducing the interaction between FgNTH and FgPK, and synergizes with DMI fungicides against F. graminearum by decreasing FgCYP51A and FgCYP51B expression.

High-Performance Cathode Materials for Potassium-Ion Batteries: Structural Design and Electrochemical Properties.

Due to the obvious advantage in potassium reserves, potassium-ion batteries (PIBs) are now receiving increasing research attention as an alternative energy storage system for lithium-ion batteries (LIBs). Unfortunately, the large size of K+ makes it a challenging task to identify suitable electrode materials, particularly cathode ones that determine the energy density of PIBs, capable of tolerating the serious structural deformation during the continuous intercalation/deintercalation of K+ . It is therefore of paramount importance that proper design principles of cathode materials be followed to ensure stable electrochemical performance if a practical application of PIBs is expected. Herein, the current knowledge on the structural engineering of cathode materials acquired during the battle against its performance degradation is summarized. The K+ storage behavior of different types of cathodes is discussed in detail and the structure-performance relationship of materials sensitive to their different lattice frameworks is highlighted. The key issues facing the future development of different categories of cathode materials are also highlighted and perspectives for potential approaches and strategies to promote the further development of PIBs are provided.

High-Performance Cathode of Sodium-Ion Batteries Enabled by a Potassium-Containing Framework of K0.5Mn0.7Fe0.2Ti0.1O2.

Sodium-ion batteries (SIBs) are promising candidates for large-scale electric energy storage with abundant sodium resources. However, their development is challenged by the availability of satisfactory cathode materials with stable framework to accommodate the transportation of large-sized Na+ (1.02 Å), whose continuous insertion/extraction can easily cause irreversible volumetric deformation in the crystalline material, leading to inevitable structural failure and capacity fading. Here, different from the previous synthesis efforts targeting at Na+ containing compounds, we unveil the possibility of achieving a highly reversible sodiation/desodiation process by resorting to a K+-based layered metal oxide formulated as K0.5Mn0.7Fe0.2Ti0.1O2 (KMFT), which is a P2 type in structure with a wide interlayer spacing to sit K+ (1.38 Å). We demonstrate that an initial K+/Na+ exchange can introduce Na+ into the lattice while a small amount of K+ remains inside, which plays a significant role in ensuring enlarged channels for a fast and stable Na+ diffusion. The KMFT electrode delivers a high initial discharge capacity of 147.1 mA h g-1 at 10 mA g-1 and outstanding long cycling stability with capacity retention of 71.5% after 1000 cycles at 500 mA g-1. These results provide a new design strategy for the development of stable SIBs cathodes to facilitate their future applications.

Facile Synthesis of Hollow Carbon Nanospheres and Their Potential as Stable Anode Materials in Potassium-Ion Batteries.

Hollow carbon nanospheres (HCNs) have found broad applications in a large variety of application fields. Unfortunately, HCNs are known for their tedious operations and are incompetent for scalable synthesis for those widely adopted nanocasting-based routes. Here, we report a facile and highly efficient method for the creation of hollow carbon structures by tuning the growth kinetics of its polymeric precursor. We identified that a controlled polymerization of Cu2+-poly(m-phenylenediamine) (Cu-PmPD) could form nanospheres with modulated inner chemical inhomogeneity, where the core of the particles was low in polymerization degree and water soluble, whereas the outer part was water insoluble. Therefore, a simple water washing of the prepared polymeric particles directly formed hollow nanospheres with a good control on the structural features including their cavity size and shell thickness. HCNs were formed through a following heat treatment and were able to exhibit promising potential as a stable anode material when tested in potassium-ion batteries.