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Idiopathic pulmonary arterial hypertension (IPAH) is a disease with complex etiology. Currently, IPAH treatment is limited, and patients' prognosis is poor. This study aimed to explore new therapeutic targets in IPAH through bioinformatics. Two data sets (GSE113439 and GSE130391) meeting the requirements were obtained from the Gene Expression Omnibus (GEO) database. Then, differentially expressed genes (DEGs) were identified and analyzed by NetworkAnalyst platform. By enriching Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG), we examined the function of DEGs. A protein-protein interaction (PPI) network was constructed to identify central genes using the CytoNCA plug-in. Finally, four central genes, ASPM, CENPE, NCAPG, and TOP2A, were screened out. We selected NCAPG for protein-level verification. We established an animal model of PAH and found that the expression of NCAPG was significantly increased in the lung tissue of PAH rats. In vitro experiments showed that the expression of NCAPG was significantly increased in proliferative pulmonary arterial smooth muscle cells (PASMCs). When NCAPG of PASMCs was knocked down, the cell proliferation was inhibited, which suggested that NCAPG was related to the proliferation of PASMCs. Therefore, these results may provide new therapeutic targets for IPAH.
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Proteínas de Ciclo Celular , Miocitos del Músculo Liso , Hipertensión Arterial Pulmonar , Animales , Proteínas de Ciclo Celular/genética , Proliferación Celular , Biología Computacional , Hipertensión Pulmonar Primaria Familiar/metabolismo , Humanos , Miocitos del Músculo Liso/citología , Proteínas del Tejido Nervioso/metabolismo , Hipertensión Arterial Pulmonar/genética , Arteria Pulmonar/citología , RatasRESUMEN
The built-in electric field generated by polar materials is one of the most effective strategies to promote the separation of photogenerated electron-hole pairs in the field of photocatalysis. However, because of the complexity and diversity of the built-in electric field in polar materials, it is not clear how to enhance the photocatalytic performance and how to control the polar electric field effectively. To this end, four-layered bismuth oxyhalides, BiOX, and BiOXO3 (X = Br, I) were synthesized by a simple hydrothermal method. X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analysis confirmed that they all have the structure characteristics of a sillenite phase. Scanning electron microscopy images show that they all have the morphology of nanosheets. Among them, BiOBrO3 was successfully synthesized and characterized for the first time in the present work. The order of photocatalytic performance (including carrier's lifetime, photocurrent density, and H2 evolution rate) of the four compounds is listed as follows: BiOBrO3 > BiOI > BiOIO3 > BiOBr. In the bulk of the BiOXO3 photocatalyst, the spontaneous polar built-in electric field along the [001] direction is the crucial factor to inhibit the recombination of photogenerated electron-hole pairs, while the surface polar electric field in BiOI can outstandingly inhibit the recombination of photogenerated electron-hole pairs due to the breaking of the mirror symmetry. Therefore, regulating the microstructure and composition of the structure unit, which generates the built-in electric field, can indeed control the magnitude, direction, and effects of built-in electric fields. In practice, we should carefully adjust the strategy according to the actual situation so as to reasonably design and use the polar electric field, giving full play to its role and enhancing the photocatalytic performance.
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Nanoporous TiNb2 O7 (NPTNO) material is synthesized by a sol-gel method with an ionic liquid (IL) as the nanoporous structure directing template. NPTNO exhibits a high reversible capacity of 210 mAh g-1 even at the charging rate of 50 C and an excellent cyclability of half-cell capacity retention of 74% for 1000 cycles at 5 C and LiNi0.5 Mn1.5 O4 -coupled full-cell capacity retentions of 81% and 87% for 1000 cycles at 1 C and 2 C, respectively. The studies of the 1000 cycled NPTNO electrode illustrate that the IL-directed mesoporous structure can enhance the cyclability of NPTNO cells due to the alleviation of repetitive mechanical stress and volume fluctuation induced by the repetitive Li+ insertion-extraction processes. The measured Li+ diffusion coefficients from the galvanostatic intermittent titration technique suggest that the IL-templating strategy indeed ensures the fast rechargeability of NPTNO cells based on the fast Li+ diffusion kinetics. Benefitting from the nanoporous structure, NPTNO with unhindered Li+ diffusion pathways achieves a superior rate capability in the titanium-based oxide materials and the best full-cell cyclability in the TNO materials. Therefore, the templating potential of IL is demonstrated, and the superb electrochemical performance establishes the IL-directed NPTNO as a promising anode candidate for fast-rechargeable LIBs.
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Hydrothermal and solid-state reaction methods are commonly used to prepare the delafossite CuCrO2 photocatalyst. It has been reported that the photocatalytic performances of CuCrO2 samples prepared by these methods are quite different. In order to explore the possible influence of different preparation processes on the photocatalytic performance and the corresponding improvement strategies, this work compares the microstructure and physicochemical properties of the samples prepared by these two methods on the basis of optimizing the process conditions. A CuCrO2 sample prepared by a hydrothermal method is characterized by high purity, low crystallinity, small grain size, and relatively higher photocatalytic activity. A CuCrO2 sample prepared by a solid-state reaction method is characterized by low purity, high crystallinity, large grain size, and relatively lower photocatalytic activity. In combination with DFT calculations, it is confirmed that the CuCrO2 sample prepared by a solid-state reaction method contains a certain amount of interstitial oxygens. Due to the presence of interstitial oxygens, CuCrO2 has strong light absorption in the visible region, presents semimetallic ferromagnetism, and changes the carrier transport, reaction process, and rate on the electrode surface. These findings will contribute to the further development of efficient CuCrO2-based photocatalysts.
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Zinc ferrite (ZnFe2O4) is a prospective lithium ion battery (LIB) material, owing to its large theoretical capacity (1000 mA h g-1). Here, we report a density functional study of the discharge process at an early stage from ZnFe2O4 up to LixZnFe2O4 (x = 2), aiming to provide a fundamental understanding of the mechanism. According to our calculations, with x increasing up to 1 the intercalation of Li+ ions prefers octahedral 16c sites, which is accompanied by Zn2+ ion displacement from tetrahedral 8a sites to 16c sites starting at x = 0.25 and a gain in stability, while the stability decreases for 1 < x ≤ 2 due to the occupation of Li+ ions at the less active tetrahedral 8a/48f/8b sites. The open-circuit voltages estimated based on the structures of stable intermediates identified by DFT calculations are in good agreement with the experimental values. Our results highlight the importance of the interplay among Li, O2-, Fe3+ and Zn2+ in enabling their high performance as LIB materials.
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The structure of pristine AgFeO2 and phase makeup of Ag0.2FeO1.6 (a one-pot composite comprised of nanocrystalline stoichiometric AgFeO2 and amorphous γ-Fe2O3 phases) was investigated using synchrotron X-ray diffraction. A new stacking-fault model was proposed for AgFeO2 powder synthesized using the co-precipitation method. The lithiation/de-lithiation mechanisms of silver ferrite, AgFeO2 and Ag0.2FeO1.6 were investigated using ex situ, in situ, and operando characterization techniques. An amorphous γ-Fe2O3 component in the Ag0.2FeO1.6 sample is quantified. Operando XRD of electrochemically reduced AgFeO2 and Ag0.2FeO1.6 composites demonstrated differences in the structural evolution of the nanocrystalline AgFeO2 component. As complimentary techniques to XRD, ex situ X-ray Absorption Spectroscopy (XAS) provided insight into the short-range structure of the (de)lithiated nanocrystalline electrodes, and a novel in situ high energy X-ray fluorescence nanoprobe (HXN) mapping measurement was applied to spatially resolve the progression of discharge. Based on the results, a redox mechanism is proposed where the full reduction of Ag+ to Ag0 and partial reduction of Fe3+ to Fe2+ occur on reduction to 1.0 V, resulting in a Li1+yFeIIIFeIIyO2 phase. The Li1+yFeIIIFeIIyO2 phase can then reversibly cycle between Fe3+ and Fe2+ oxidation states, permitting good capacity retention over 50 cycles. In the Ag0.2FeO1.6 composite, a substantial amorphous γ-Fe2O3 component is observed which discharges to rock salt LiFe2O3 and Fe0 metal phase in the 3.5-1.0 V voltage range (in parallel with the AgFeO2 mechanism), and reversibly reoxidizes to a nanocrystalline iron oxide phase.
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In this study, chlorogenic acid (CA), piceatannol (PIC), epigallocatechin-3-gallate (EGCG) and ferulic acid (FA) was selected to explore the influence of polyphenol on the structural properties of wheat germ albumin (WGA) and wheat germ globulin (WGG). The emulsifying properties of the emulsions prepared by WGA-EGCG complex were also evaluated. The results indicated that all polyphenols could significantly enhance the antioxidant capacity of WGA and WGG. In particular, EGCG increased the ratio of random coil in WGA and WGG, resulting in protein unfolding and shifting from an order to disorder structure. In addition, lipid oxidation and protein oxidation of the soybean oil emulsion was significantly slowed down by WGA-EGCG. The stability of the emulsions under various environmental stress and the storage time was significantly improved by WGA-EGCG. These findings can provide a reference for expanding the application of wheat germ protein in food industry.
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Emulsiones , Globulinas , Polifenoles , Triticum , Triticum/química , Polifenoles/química , Polifenoles/farmacología , Globulinas/química , Emulsiones/química , Albúminas/química , Conformación Proteica , Proteínas de Plantas/química , Antioxidantes/química , Antioxidantes/farmacologíaRESUMEN
The potential of adverse events (AEs) after thoracic endovascular aortic repair (TEVAR) in patients with type B aortic dissection (TBAD) has been reported. To avoid the occurrence of AEs, it is important to recognize high-risk population for prevention in advance. The data of 261 patients with TBAD who received TEVAR between June 2017 and June 2021 at our medical center were retrospectively reviewed. After the implementation of exclusion criteria, 172 patients were finally included, and after 2.8 years (range from 1 day to 5.8 years) of follow up, they were divided into AEs (n = 41) and non-AEs (n = 131) groups. We identified the predictors of AEs, and a prediction model was constructed to calculate the specific risk of postoperative AEs at 1, 2, and 3 years, and to stratify patients into high-risk (n = 78) and low-risk (n = 94) group. The prediction model included seven predictors: Age > 75 years, Lower extremity malperfusion (LEM), NT-proBNP > 330 pg/ml, None distal tear, the ratio between the diameter of the ascending aorta and descending aorta (A/D ratio) > 1.2, the ratio of the area of the false lumen to the total aorta (FL ratio) > 64%, and acute TEVAR, which exhibited excellent predictive accuracy performance and discriminatory ability with C statistic of 82.3% (95% CI 77.3-89.2%). The prediction model was contributed to identify high-risk patients of postoperative AEs, which may serve to achievement of personalized treatment and follow-up plans for patients.
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Aneurisma de la Aorta Torácica , Disección Aórtica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Humanos , Anciano , Reparación Endovascular de Aneurismas , Implantación de Prótesis Vascular/efectos adversos , Aneurisma de la Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/etiología , Estudios Retrospectivos , Procedimientos Endovasculares/efectos adversos , Resultado del Tratamiento , Factores de Tiempo , Aorta Torácica/cirugía , Disección Aórtica/cirugía , Factores de RiesgoRESUMEN
Multiple phenolic substances have been shown to promote SIRT3 expression, however, few studies have focused on the effects of these phenolics on SIRT3 enzyme activity. This study constructed a variety of reaction systems to elucidate the mechanisms by which different polyphenols affect SIRT3 enzyme activity. The results showed that acP53317-320 was the most suitable substrate among the five acetylated peptide substrates (Kcat/Km = 74.85 ± 1.86 M-1â¢s-1). All the phenolic compounds involved in the experiment inhibited the enzymatic activity of SIRT3, and the lowest IC50 among them was quercetin (0.12 ± 0.01 mM) and the highest was piceatannol (1.29 ± 0.08 mM). Their inhibition types were mainly competitive and mixed. In addition, piceatannol was found to be a natural SIRT3 agonist by enzyme kinetic analysis and validation of deacetylation efficiency. This study will provide a useful reference for polyphenol modulation of SIRT3 dosage, as well as the development and application of polyphenol-based SIRT3 activators and agonists.
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Polifenoles , Sirtuina 3 , Sirtuina 3/metabolismo , Polifenoles/farmacología , Polifenoles/química , Acetilación , Humanos , Cinética , Estilbenos/farmacología , Estilbenos/químicaRESUMEN
BACKGROUND: Maternal nutrition can have a profound effect on fetal growth, development, and subsequent infant birth weight. However, little is known regarding the influence of prepregnancy dietary patterns. OBJECTIVES: This study aimed to explore the effects between prepregnancy dietary patterns on birth weight. METHODS: This study included 911 singleton live-born infants from the Taicang and Wuqiang Mother-Child Cohort Study (TAWS). Baseline information and prepregnancy diet data were collected during early pregnancy. Newborn birth information was obtained from the Wuqiang County Hospital. Macrosomia, defined as a birth weight of ≥4000 g, and large for gestational age (LGA), defined as a birth weight higher than the 90th percentile for the same sex and gestational age, were the outcomes of interest. The dietary patterns were extracted using principal component analysis. Logistic regression models were used to investigate the association between prepregnancy dietary patterns (in tertiles) and macrosomia and LGA, and subgroup analysis was further explored by pre-pregnancy body mass index (BMI). RESULTS: Four dietary patterns were identified based on 15 food groups. These patterns were named as "cereals-vegetables-fruits," "vegetables-poultry-aquatic products," "milk-meat-eggs," and "nuts-aquatic products-snacks." After adjusting for sociodemographic characteristics, pregnancy complications, and other dietary patterns, greater adherence to the "cereals-vegetables-fruits" pattern before pregnancy was associated with a higher risk of macrosomia (adjusted OR = 2.220, 95% CI: 1.018, 4.843), while greater adherence to the "nuts-aquatic products-snacks" pattern was associated with a lower risk of macrosomia (adjusted OR = 0.357, 95% CI: 0.175, 0.725) compared to the lowest tertile. No significant association was observed between prepregnancy dietary patterns and LGA. However, after subgroup analysis of pre-pregnancy BMI, "cereals-vegetables-fruits" pattern was associated with an increased risk of LGA in overweight and obese mothers (adjusted OR = 2.353, 95% CI: 1.010, 5.480). CONCLUSIONS: An unbalanced pre-pregnancy diet increases the risk of macrosomia and LGA, especially in overweight or obese women before pre-pregnancy.
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Macrosomía Fetal , Sobrepeso , Embarazo , Recién Nacido , Lactante , Femenino , Humanos , Peso al Nacer , Macrosomía Fetal/etiología , Macrosomía Fetal/complicaciones , Estudios de Cohortes , Sobrepeso/complicaciones , Estudios Prospectivos , Factores de Riesgo , Obesidad/complicaciones , Aumento de Peso , Índice de Masa CorporalRESUMEN
Skeletal muscle dysfunction caused by obesity is characterized by the decline in mitochondrial content and function. 5-Heptadecylresorcinol (AR-C17) is a specific bioactive component derived from whole wheat and rye, which has been evidenced to improve obesity-associated skeletal muscle dysregulation. However, the mechanism underlying its protective activity requires further exploration. Herein, we found that AR-C17 (5, 10, and 20 µM) intervention reversed PA-induced (0.5 mM) reduction in mitochondrial content, mitochondrial membrane potential, and mitochondrial energy metabolism in C2C12 cells. Meanwhile, AR-C17 evidently alleviated PA-mediated myotube mitochondrial dysfunction via elevating mitochondria autophagy flux and upregulating the expression level of autophagy-related protein, while this effect was abolished by an autophagy inhibitor (3-MA). Further analysis showed that SIRT3-FOXO3A-PINK-Parkin-mediated mitophagy was involved in the modulation of myocyte mitochondrial dysfunction by AR-C17. In addition, AR-C17 administration (30 and 150 mg/kg/day) significantly improved high-fat-diet-induced mitochondrial dysregulation in mice skeletal muscle tissue via SIRT3-dependent mitophagy. Our findings indicate that skeletal muscle cells are responsive to AR-C17, which improves myogenesis and mitophagy in vitro and in vivo.
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Mitofagia , Sirtuina 3 , Ratones , Animales , Sirtuina 3/metabolismo , Sirtuina 3/farmacología , Transducción de Señal , Músculo Esquelético/metabolismo , Mitocondrias/metabolismo , Obesidad/tratamiento farmacológico , Obesidad/genética , Obesidad/metabolismoRESUMEN
Transformer, first applied to the field of natural language processing, is a type of deep neural network mainly based on the self-attention mechanism. Thanks to its strong representation capabilities, researchers are looking at ways to apply transformer to computer vision tasks. In a variety of visual benchmarks, transformer-based models perform similar to or better than other types of networks such as convolutional and recurrent neural networks. Given its high performance and less need for vision-specific inductive bias, transformer is receiving more and more attention from the computer vision community. In this paper, we review these vision transformer models by categorizing them in different tasks and analyzing their advantages and disadvantages. The main categories we explore include the backbone network, high/mid-level vision, low-level vision, and video processing. We also include efficient transformer methods for pushing transformer into real device-based applications. Furthermore, we also take a brief look at the self-attention mechanism in computer vision, as it is the base component in transformer. Toward the end of this paper, we discuss the challenges and provide several further research directions for vision transformers.
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Reversible lattice oxygen redox reactions offer the potential to enhance energy density and lower battery cathode costs. However, their widespread adoption faces obstacles like substantial voltage hysteresis and poor stability. The current research addresses these challenges by achieving a non-hysteresis, long-term stable oxygen redox reaction in the P3-type Na2/3Cu1/3Mn2/3O2. Here we show this is accomplished by forming spin singlet states during charge and discharge. Detailed analysis, including in-situ X-ray diffraction, shows highly reversible structural changes during cycling. In addition, local CuO6 Jahn-Teller distortions persist throughout, with dynamic Cu-O bond length variations. In-situ hard X-ray absorption and ex-situ soft X-ray absorption study, along with density function theory calculations, reveal two distinct charge compensation mechanisms at approximately 3.66 V and 3.99 V plateaus. Notably, we observe a Zhang-Rice-like singlet state during 3.99 V charging, offering an alternative charge compensation mechanism to stabilize the active oxygen redox reaction.
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Pathological angiogenesis plays a major role in many disease processes, including cancer and diabetic retinopathy. Antiangiogenic therapy is a potential management for pathologic angiogenesis. The novel synthetic compound 221S-1a, derived from captopril, tanshinol and borneol, may have antiangiogenic properties. On the basis of MS, NMR and HPLC analysis, the structure of 221S-1a was identified. The cellular uptake and metabolism of this compound was also observed. Next, the antiangiogenic properties of 221S-1a were evaluated in tumor-xenograft and OIR models in vivo. The inhibitory properties of 221S-1a on endothelial cell proliferation, migration, tube formation and sprouting were detected in vitro. Furthermore, 221S-1a induced G1/S phase arrest was detected by PI staining flow cytometry analysis and Cyclin D, Cyclin E expression. 221S-1a inhibited ERK1/2 activation and nuclear translocation, in addition to downregulation of c-Myc, a transcription factor that regulates cell cycle progression. Molecular docking indicated the interaction of 221S-1a with the ATP-binding site of ERK2, leading to the inhibition of ERK2 phosphorylation and a concomitant inhibition of ERK1 phosphorylation. In conclusion, 221S-1a inhibited the G1/S phase transition by blocking the ERK1/2/c-Myc pathway to reduce tumor and OIR retinal angiogenesis. These novel findings suggest that 221S-1a is a potential pharmacologic candidate for treating pathological angiogenesis.
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Proteínas Proto-Oncogénicas c-myc , Transducción de Señal , Humanos , Simulación del Acoplamiento Molecular , Neovascularización Patológica/tratamiento farmacológico , Proliferación CelularRESUMEN
A synthetic iron model can process both halogenation and hydroxylation with vague selectivity, which is different from halogenase even though these structures are used for the simulation of halogenase. The key factor of the synthetic oxo-iron model mediated hydroxylation or the halogenation is still under debate. Herein density functional theory calculation is used to investigate the hydroxylation versus halogenation of propylene by the complex [FeIV(O)(TQA)(X)]+ (X = F, Cl, Br). Our results suggest that a concerted rebound mechanism (between the -X and the hydroxyl ligands after the hydrogen abstraction) leads to the formation of two different kinds of products.
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Aims: To investigate the risk factors, clinical features, and prognostic factors of patients with premature acute myocardial infarction (AMI). Materials and methods: A retrospective cohort study of patients with AMI included in data from the West China Hospital of Sichuan University from 2011 to 2019 was divided into premature AMI (aged < 55 years in men and < 65 years in women) and non-premature AMI. Patients' demographics, laboratory tests, Electrocardiography (ECG), cardiac ultrasound, and coronary angiography reports were collected. All-cause death after incident premature MI was enumerated as the primary endpoint. Results: Among all 8,942 AMI cases, 2,513 were premature AMI (79.8% men). Compared to the non-premature AMI group, risk factors such as smoking, dyslipidemia, overweight, obesity, and a family history of coronary heart disease (CHD) were more prevalent in the premature AMI group. The cumulative survival rate of patients in the premature AMI group was significantly better than the non-premature AMI group during a mean follow-up of 4.6 years (HR = 0.27, 95% CI 0.22-0.32, p < 0.001). Low left ventricular ejection fraction (LVEF) (Adjusted HR 3.00, 95% CI 1.85-4.88, P < 0.001), peak N-terminal pro-B-type natriuretic peptide (NT-proBNP) level (Adjusted HR 1.34, 95% CI 1.18-1.52, P < 0.001) and the occurrence of in-hospital major adverse cardiovascular and cerebrovascular events (MACCEs) (Adjusted HR 2.36, 95% CI 1.45-3.85, P = 0.001) were predictors of poor prognosis in premature AMI patients. Conclusion: AMI in young patients is associated with unhealthy lifestyles such as smoking, dyslipidemia, and obesity. Low LVEF, elevated NT-proBNP peak level, and the occurrence of in-hospital MACCEs were predictors of poor prognosis in premature AMI patients.
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Five phosphorescent metal-anion radical coordination polymers based on a new anion radical ligand generated by in situ deprotonation of a stable zwitterionic radical are described. The N,O,N-tripodal anion radical ligand links metal cations, which leads to five isostructural coordination polymers, [M(3)(bipo(-.))(4)(L)(2)](n) (M=Cd or Mn, Hbipo(-.)=2,3'-biimidazo[1,2-a]pyridin-2'-one, L=Cl(-), HCOO(-) or SCN(-)). The isostructural coordination polymers exhibit novel one-dimensional spirocycle-like structures. Three isostructural Cd(II) coordination polymers display unusual phosphorescent color changes (blue, yellow, and white) induced by terminal anions. Significantly, the Cd(II) coordination polymer with terminal Cl(-) possesses moderate quantum yield, and shows a bright white-light phosphorescence emission, which is independent of excitation wavelength and can even be excited by visible light. Upon adjusting the metal cation to Mn(II), two isostructural Mn(II) coordination polymers reveal deep-blue-light phosphorescence emissions that are independent of terminal anions. As radical-based coordination polymers, some of them show antiferromagnetic interactions between radical species or radical and metal center.
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Disordered rocksalt (DRX) cathodes have attracted interest due to their high capacity and compositional flexibility (e.g., Co-free chemistries). However, the sloping voltage profile and gradual capacity fade during cycling have hindered the widespread adoption of these materials. Simulations predict that fluorine substitution in DRX cathodes will improve their capacity, rate performance, and cyclability. In this study, we use a fluidized bed reactor to fluorinate a model Li-rich DRX composition (Li1.15Ni0.375Ti0.375Mo0.1O2, NTMO) to investigate how fluorine content impacts the cathode's structure and electrochemical performance. Instead of substituting O with F to form oxyfluoride phases, direct fluorination of DRX cathodes leads to the formation of LiF surface films, which improves the specific energy and capacity retention. This study demonstrates the feasibility of direct fluorination to improve the electrochemical performance of high-voltage cathodes by tuning the material's surface chemistry.
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Spinel transition metal oxides (TMOs) have emerged as promising anode materials for lithium-ion batteries. It has been shown that reducing their particle size to nanoscale dimensions benefits overall electrochemical performance. Here, we use in situ transmission electron microscopy to probe the lithiation behavior of spinel ZnFe2O4 as a function of particle size. We have found that ZnFe2O4 undergoes an intercalation-to-conversion reaction sequence, with the initial intercalation process being size dependent. Larger ZnFe2O4 particles (40 nm) follow a two-phase intercalation reaction. In contrast, a solid-solution transformation dominates the early stages of discharge when the particle size is about 6-9 nm. Using a thermodynamic analysis, we find that the size-dependent kinetics originate from the interfacial energy between the two phases. Furthermore, the conversion reaction in both large and small particles favors {111} planes and follows a core-shell reaction mode. These results elucidate the intrinsic mechanism that permits fast reaction kinetics in smaller nanoparticles.
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Advances in liquid-phase exfoliation and surfactant-directed anisotropic growth of two-dimensional (2D) nanosheets have enabled their rapid development. However, it remains challenging to develop assembly strategies that lead to the construction of 2D nanomaterials with well-defined geometry and functional nanoarchitectures that are tailored to specific applications. Here we report a facile self-assembly method leading to the controlled synthesis of 2D transition metal oxide (TMO) nanosheets containing a high density of holes. We utilize graphene oxide sheets as a sacrificial template and Pluronic copolymers as surfactants. By using ZnFe2O4 (ZFO) nanoparticles as a model material, we demonstrate that by tuning the molecular weight of the Pluronic copolymers we can incorporate the ZFO particles and tune the size of the holes in the sheets. The resulting 2D ZFO nanosheets offer synergistic characteristics including increased electrochemically active surface areas, shortened ion diffusion paths, and strong inherent mechanical properties, leading to enhanced lithium-ion storage properties. Postcycling characterization confirms that the samples maintain structural integrity after electrochemical cycling. Our findings demonstrate that this template-assisted self-assembly method is a useful bottom-up route for controlled synthesis of 2D nanoarchitectures, and these holey 2D nanoarchitectures are promising for improving the electrochemical performance of next-generation lithium-ion batteries.