IRX5 suppresses osteogenic differentiation of hBMSCs by inhibiting protein synthesis.

In our previous study, IRX5 has been revealed a significant role in adipogenesis of hBMSCs. Considering the expansion of adipose tissue in bone marrow in aged and ovariectomy-related osteoporosis, the effect of IRX5 on the osteogenesis of BMSCs still needs to be elucidated. In vivo, models of aging-induced and ovariectomy-induced osteoporotic mice, and in vitro studies of IRX5 gene gain- and loss-of-function in hBMSCs were employed. Histology, immunofluorescence, qRT-PCR, and Western blot analysis were performed to detect the functions of IRX5 in hBMSCs osteogenic differentiation. RNA-seq, transmission electron microscopy, Seahorse mito-stress assay, and Surface Sensing of Translation assay were conducted to explore the effect of mammalian/mechanistic target of rapamycin (mTOR)-mediated ribosomal translation and mitochondrial functions in the regulation of hBMSCs differentiation by IRX5. As a result, elevated IRX5 protein expression levels were observed in the bone marrow of osteoporotic mice compared to normal mice. IRX5 overexpression attenuated osteogenic processes, whereas IRX5 knockdown resulted in enhanced osteogenesis in hBMSCs. RNA-seq and enrichment analysis unveiled that IRX5 overexpression exerted inhibitory effects on ribosomal translation and mitochondrial functions. Furthermore, the application of the mTOR activator, MHY1485, effectively reversed the inhibitory impact of IRX5 on osteogenesis and mitochondrial functions in hBMSCs. In summary, our findings suggest that IRX5 restricts mTOR-mediated ribosomal translation, consequently impairing mitochondrial OxPhos, which in turn results in osteogenic dysfunction of hBMSCs.

Composites of W18O49 Nanowires with g-C3N4/RGO Nanosheets for Broadband Light-Driven Photocatalytic Wastewater Purification.

Developing a photocatalyst that can effectively utilize the full solar spectrum remains a high-priority objective in the ongoing pursuit of efficient light-to-chemical energy conversion. Herein, the ternary nanocomposite g-C3N4/RGO/W18O49 (CN/RGO/WO) was constructed and characterized by a variety of techniques. Remarkably, under the excitation of photon energies ranging from the ultraviolet (UV) to the near-infrared (NIR) region, the photocatalytic performance of the CN/RGO/WO nanocomposite exhibited a significant enhancement compared with single component g-C3N4 or W18O49 nanosheets for the degradation of methyl orange (MO). The MO photodegradation rate of the optimal CN/1.0 wt% RGO/45.0 wt% WO catalyst reached 0.816 and 0.027 min-1 under UV and visible light excitation, respectively. Even under low-energy NIR light, which is not sufficient to excite g-C3N4, the MO degradation rate can still reach 0.0367 h-1, exhibiting a significant enhancement than pure W18O49. The outstanding MO removal rate and stability were demonstrated by CN/RGO/WO nanocomposites, which arise from the synergistic effect of localized surface plasmon resonance effect induced by W18O49 under vis-NIR excitation and the Z-scheme nanoheterojunction of W18O49 and g-C3N4. In this work, we have exploited the great potential of integrating nonmetallic plasmonic nanomaterials and good conductor RGO to construct high-performance g-C3N4-based full-solar spectral broadband photocatalysts.

Hotspots and frontiers of the relationship between gastric cancer and depression: A bibliometric study.

BACKGROUND: A significant relationship between gastric cancer (GC) and depression has been found in the last 20 years. However, there is no comprehensive information that helps researchers find popular and potential research directions on GC and depression. AIM: To determine the research status and hotspots by bibliometric analysis of relevant publications on the relationship between GC and depression. METHODS: We used the Web of Science Core Collection to search and collate the literature on GC and depression from 2000 to 2022 on 31 May, 2023. Then, visualization analysis was performed using VOSviewer software (version 1.6.19) and the Bibliometrix package in R software. RESULTS: We retrieved 153 pertinent publications from 2000 to 2022. The annual publication count showed an overall upward trend. China had the most prominent publications and significant contributions to this field (n = 64, 41.83%). Before 2020, most studies focused on "the effect of GC on the development and progression of depression in patients." The latest research trends indicate that "the effect of depression on the occurrence and development of GC and its mechanism" will receive more attention in the future. CONCLUSION: The study of "the effect of depression on the occurrence and development of GC and its mechanism" has emerged as a novel research theme over the past two years, which may become a research hotspot in this field. This study provides new insights into the hotpots and frontiers of the relationship between GC and depression, potentially guiding researchers toward hot research topics in the future.

A descriptive study based on the comparison of ChatGPT and evidence-based neurosurgeons.

ChatGPT is an artificial intelligence product developed by OpenAI. This study aims to investigate whether ChatGPT can respond in accordance with evidence-based medicine in neurosurgery. We generated 50 neurosurgical questions covering neurosurgical diseases. Each question was posed three times to GPT-3.5 and GPT-4.0. We also recruited three neurosurgeons with high, middle, and low seniority to respond to questions. The results were analyzed regarding ChatGPT's overall performance score, mean scores by the items' specialty classification, and question type. In conclusion, GPT-3.5's ability to respond in accordance with evidence-based medicine was comparable to that of neurosurgeons with low seniority, and GPT-4.0's ability was comparable to that of neurosurgeons with high seniority. Although ChatGPT is yet to be comparable to a neurosurgeon with high seniority, future upgrades could enhance its performance and abilities.

La-doped NiWO4 coupled with reduced graphene oxide for effective electrochemical determination of diphenylamine.

Diphenylamine (DPA) is a harmful pesticide widely used to control post-harvest scald of fruits. In this study, rapid and sensitive determination of DPA was realized by the development of an effective electrochemical sensor, which was fabricated by coupling La-doped NiWO4 nanoparticles (La/NiWO4) with reduced graphene oxide (rGO), and the obtained rGO/La/NiWO4 nanocomposite was modified on glassy carbon electrodes (GCEs). The morphologies, structures and compositions were well characterized, and the effects of La doping and the introduction of rGO on the crystal structure and electrochemical performance were discussed. The incorporation of both La and rGO was found to enhance the active surface area and improve conductivity, resulting in the enhanced electrocatalytic performance of rGO/La/NiWO4/GCE, including a wide linear range (0.01-500 µM), a low detection limit (0.0058 µM) and high sensitivity (1.778 µA µM-1 cm-2). The fabricated sensor was further used for DPA detection in fresh apple extract to evaluate its practicality and demonstrated excellent recoveries ranging from 99.52 to 104.70%.

The construction of a heterostructured RGO/g-C3N4/LaCO3OH composite with enhanced visible light photocatalytic activity for MO degradation.

The construction of a heterojunction and the introduction of a cocatalyst can both promote the transfer of photogenerated electrons, which are effective strategies to enhance photocatalytic efficiency. In this paper, a ternary RGO/g-C3N4/LaCO3OH composite was synthesized by constructing a g-C3N4/LaCO3OH heterojunction and introducing a non-noble metal cocatalyst RGO through hydrothermal reactions. TEM, XRD, XPS, UV-vis diffuse reflectance spectroscopy, photo-electrochemistry and PL tests were carried out to characterize the structures, morphologies and carrier separation efficiencies of products. Benefiting from the boosted visible light absorption capability, reduced charge transfer resistance and facilitated photogenerated carrier separation, the visible light photocatalytic activity of the ternary RGO/g-C3N4/LaCO3OH composite was effectively improved, resulting in a much increased MO (methyl orange) degradation rate of 0.0326 min-1 compared with LaCO3OH (0.0003 min-1) and g-C3N4 (0.0083 min-1). Moreover, by combining the results of the active species trapping experiment with the bandgap structure of each component, the mechanism of the MO photodegradation process was proposed.

Hydrophobic deep eutectic solvent-based ultrasonic-assisted liquid-liquid microextraction combined with GC for eugenol, isoeugenol, and methyl isoeugenol determination in aquatic products.

The use of deep eutectic solvents (DESs) has great prospects because of the green and efficient characteristics, which can be used for developing analytical methods for foods. In this research, assisted by ultrasonic waves, a liquid-liquid microextraction detection method combined with gas chromatography was established for three anaesthetics (eugenol, isoeugenol, and methyl isoeugenol) in aquatic food. The processing conditions including the components, ratio of hydrogen bond acceptor and hydrogen bond donor, DES volume, ultrasonic time, and pH were evaluated and optimised to improve the extraction efficiency, which was based on the DES structures and properties. In-house method validation was carried out by applying to real samples. A Thymol: levulinic acid DES (with a molar ratio of 1:2) was used as the extractant and the recoveries were as high as 93-101% for eugenol, 90-100% for methyl isoeugenol, and 86-94% for isoeugenol with RSDs <5% under optimum conditions. The limit of detection and quantification of the eugenol compounds were 0.08-0.10 µg/mL and 0.26-0.33 µg/mL, respectively. The method has green credentials and comparable LOD to homologous apparatus, which can be used for the determination of eugenol components in aquatic food.

Exosome-Mediated Immunosuppression in Tumor Microenvironments.

Exosomes are membranous structures secreted by nearly all cell types. As critical messengers for intercellular communication, exosomes deliver bioactive cargoes to recipient cells and are involved in multiple physiopathological processes, including immunoregulation. Our pioneering study revealed that cancer cells release programmed death-ligand 1-positive exosomes into the circulation to counter antitumor immunity systemically via T cells. Tumor cell-derived exosomes (TDEs) also play an immunosuppressive role in other immunocytes, including dendritic cells (DCs), macrophages, natural killer (NK) cells, and myeloid-derived suppressor cells (MDSCs). Moreover, exosomes secreted by nontumor cells in the tumor microenvironments (TMEs) also exert immunosuppressive effects. This review systematically provides a summary of the immunosuppression induced by exosomes in tumor microenvironments, which modulates tumor growth, invasion, metastasis, and immunotherapeutic resistance. Additionally, therapeutic strategies targeting the molecular mechanism of exosome-mediated tumor development, which may help overcome several obstacles, such as immune tolerance in oncotherapy, are also discussed. Detailed knowledge of the specific functions of exosomes in antitumor immunity may contribute to the development of innovative treatments.

Alkali etching zinc and manganese silicates derived from natural green algaes for supercapacitors with enhanced electrochemical properties.

A facile novel method of alkali etching was proposed to enhance the application of metal-silicates in supercapacitors. First, 3D N, S, P-doped C-zinc-silicate (C-ZnSi), and C-manganese-silicate (C-MnSi) were derived from calcined green algaes (GAs) in a N2 atmosphere. Second, the synthesized products were soaked in a 3.0 M NaOH aqueous solution for alkali etching (soaked for 6, 12 and 24 h) to obtain the etching metal silicates (e-C-ZnSi and e-C-MnSi). This method can yield a higher specific surface area and more pores, and this in turn can improve the electrochemical performance. In the three-electrode system, e-C-ZnSi and e-C-MnSi, which were soaked in NaOH solution for 12 h, exhibited the highest specific capacitances and cycling performance. Solid-state hybrid supercapacitor (HSC) devices were manufactured using C-MSi, e-C-MSi (M = Zn and Mn), and activated carbon (AC) (denoted as C-MSi//AC and e-C-MSi//AC). In the two-electrode system, the e-C-MSi//AC HSC devices exhibited higher areal specific capacitances and energy densities and better cycle performance than those of C-MSi//AC, especially e-C-MSi//AC-12 h HSC devices, which exhibited the best electrochemical properties. This study demonstrated that the naturally polluted GAs can be used as a reusable silica source for the synthesis of supercapacitors. Furthermore, alkali etching can enhance the electrochemical performance of metal silicates and can be used to prepare electrode materials applied for high-performance supercapacitors.

Rice-like and rose-like zinc silicates anchored on amorphous carbon derived from natural reed leaves for high-performance supercapacitors.

3D N, S, P-doped rice-like C-Zn4Si2O7(OH)2·H2O (C-ZnSi-N2) and rose-like C-Zn2SiO4 (C-ZnSi-CO2) are derived from reed leaves and used for application in supercapacitors. The as-prepared C-ZnSi architectures with a large number of hierarchical pores and high specific surface area from reed leaves have outstanding electrochemical performance. The obtained C-ZnSi-N2 shows 341 F g-1 at the current density of 0.5 A g-1, while the C-ZnSi-CO2 exhibits 498 F g-1, and both of the C-ZnSi materials significantly retain above 99% of their capacitance after 10 000 cycles. Furthermore, the flexible solid-state asymmetric supercapacitors (ASCs) synthesized from C-ZnSi and activated carbon (denoted as C-ZnSi-N2//AC and C-ZnSi-CO2//AC) achieve a high capacitance (405 and 194 mF cm-2 at the current density of 2 mA cm-2, respectively). Besides, the ASC devices show good cycling stability for 7300 cycles with 73% and 77% capacitance retention. The results presented in this study indicate that the N, S, P-doped C-ZnSi architectures from natural reed leaves are promising and efficient materials for manufacturing high performance supercapacitors.

Interphases, Interfaces, and Surfaces of Active Materials in Rechargeable Batteries and Perovskite Solar Cells.

The ever-increasing demand for clean sustainable energy has driven tremendous worldwide investment in the design and exploration of new active materials for energy conversion and energy-storage devices. Tailoring the surfaces of and interfaces between different materials is one of the surest and best studied paths to enable high-energy-density batteries and high-efficiency solar cells. Metal-halide perovskite solar cells (PSCs) are one of the most promising photovoltaic materials due to their unprecedented development, with their record power conversion efficiency (PCE) rocketing beyond 25% in less than 10 years. Such progress is achieved largely through the control of crystallinity and surface/interface defects. Rechargeable batteries (RBs) reversibly convert electrical and chemical potential energy through redox reactions at the interfaces between the electrodes and electrolyte. The (electro)chemical and optoelectronic compatibility between active components are essential design considerations to optimize power conversion and energy storage performance. A focused discussion and critical analysis on the formation and functions of the interfaces and interphases of the active materials in these devices is provided, and prospective strategies used to overcome current challenges are described. These strategies revolve around manipulating the chemical compositions, defects, stability, and passivation of the various interfaces of RBs and PSCs.

Fabrication of vanadium sulfide (VS4) wrapped with carbonaceous materials as an enhanced electrode for symmetric supercapacitors.

Exploring electrode materials with excellent electrochemical performance is the key to the development of applications in energy storage and conversion. Herein, three-dimensional (3D) vanadium sulfide/carbon nanotubes/reduced graphene oxide (VS4/CNTs/rGO) composite is synthesized by a simple one-step hydrothermal method. VS4 short nanorods cover the both sides of the rGO sheets, and CNTs distribute at the edge of the composite to form a sandwich-like structure, which effectively prevents the accumulation of rGO. Due to the special 3D hierarchical structure, VS4/CNTs/rGO exhibits a large specific surface area and a rich pore structure, and the addition of CNTs and rGO also improves the electrochemical properties of VS4. At 1 A·g-1, VS4/CNTs/rGO exhibits a capacitance of 497 F·g-1 (1374.0 C·g-1) in the voltage range of -1.4 to 1.4 V, which is much higher than those binary materials including CNTs/rGO, VS4/CNTs and VS4/rGO. The VS4/CNTs/rGO symmetric supercapacitor (SSC) device shows a remarkable electrochemical performance in a large potential window up to 2.2 V. The capacitance of VS4/CNTs/rGO SSC device can reach 1003.5 mF·cm-2 (2207.6 mC·cm-2) at 0.5 mA·cm-2, and it exhibits an energy density of 6.75 Wh·m-2 (72.07 Wh·kg-1) at a power density of 1.38 W·m-2 (14.69 W·kg-1). The high capacitance and energy density of the VS4/CNTs/rGO composite in the high voltage interval make it as the potential energy storage material.

Synthesis of amorphous cobalt silicate nanobelts@manganese silicate core-shell structures as enhanced electrode for high-performance hybrid supercapacitors.

Among diverse transition metal silicates (TMSs), cobalt silicate (Co2SiO4) and manganese silicate (MnSiO3) have been diffusely developed for electrode materials due to their high theoretical capacity, structural stability and simple synthetic process. In this work, Co2SiO4 nanobelts@MnSiO3 have been designed and synthesized as the enhanced electrode for high-performance hybrid supercapacitors. The one-dimensional (1D) Co2SiO4 nanobelts enhance their ability to transport electrons along the long axis, which allows current collection during the charge and discharge to improve electrochemical performances. The MnSiO3 coating can be a steady elastic buffer layer, which can protect the active materials during the charge and discharge in effect. What's more, the "core" and "shell" will both be a considerable offering to the total capacity. Sure enough, the capacitance value of Co2SiO4 nanobelts@MnSiO3 can achieve 309 F g-1 at 0.5 A g-1 accompanied by 64% capacitance retention after 10,000 cycles. And the hybrid supercapacitor (HSC) device assembled by Co2SiO4 nanobelts@MnSiO3 and activated carbon (AC) own an excellent capacitance of 384 mF cm-2 at 2 mA cm-2 accompanied by 57% capacitance retention after 2000 cycles. Meanwhile, the Co2SiO4 nanobelts@MnSiO3//AC HSC device's power density (P/W m-2) and energy density (E/Wh m-2) can reach to be 30 W m-2 and 0.77 Wh m-2, respectively. The unique and novel microstructure makes cobalt silicate and manganese silicate shine once again in excellent electrochemical performance.

Solid-state transformation of TMA-magadiite into zeolite omega and detailed insights into the crystallization process.

Herein, we have studied the crystallization of zeolite omega by the solid-state transformation of TMA-magadiite at 100 °C for 12 h. The samples prepared at different times were subjected to XRD, SEM, IR, Raman and solid MAS NMR analyses to investigate the crystallization behaviors and changes in the medium-range structure during the synthesis process and a comprehensive mechanism was proposed. It has been demonstrated that the 5Rs and 6Rs in magadiite are partially retained in the system and participate in the growth of zeolite omega. The 4Rs were formed after heating for 4 h. The synthesis time of the zeolite omega using this method is shorter than that using the magadiite hydrothermal conversion method (about 72 h), because special composition building units, which have similarities to the structure of zeolite omega, were formed and adsorbed on the surface of the TMA-magadiite, and then provided a growth surface for the synthesis of targets. In addition, recycling the waste mother liquid produced in the preparation of the precursor was done to achieve the low cost and green synthesis. Finally, several factors influencing the reaction are discussed.

Chemically Bonding NiFe-LDH Nanosheets on rGO for Superior Lithium-Ion Capacitors.

Layered double hydroxides (LDHs) have attracted tremendous interest for applications in energy harvest and storage. However, the aggregation of nanosheets compromises the accessible active sites and limits their electrochemical performance, especially at high rates. The present study reports the synthesis of highly dispersed NiFe-LDH nanosheets anchored on reduced graphene oxide (NiFe-LDH/rGO) composites chemically bonded via a facile one-step hydrothermal method. Defect-riched rGO provides abundant active sites for heterogeneous nucleation of NiFe-LDH nanosheets, achieving the much efficient charge transfer between rGO and NiFe-LDH as compared to physically mixed NiFe-LDH + rGO. The crystallite size can effectively reduce to 5.5 nm smaller than 15.1 nm of NiFe-LDH without rGO, beneficial to expose more active surface for fast ion diffusion and redox reactions. NiFe-LDH/rGO as an anode material in lithium-ion batteries shows superior lithium storage capacity with 1202 mAh g-1 after 100 cycles at 100 mA g-1 and high-rate performance with 543 mAh g-1 even at 2000 mA g-1. The corresponding lithium-ion capacitor with NiFe-LDH/rGO anode and mesoporous carbon microsphere cathode exhibits high energy density and power density simultaneously, with 133 Wh kg-1 at 25 W kg-1 and 4016 W kg-1 at 58 Wh kg-1, showing the great potential for high-performance hybrid energy storage systems.

Hydrothermal synthesis of VS4/CNTs composite with petal-shape structures performing a high specific capacity in a large potential range for high-performance symmetric supercapacitors.

Vanadium sulfide (VS4) is recognized as a good anode material for energy storage devices because of its chain-like structure and high content of sulfur. Herein, the patronite VS4 anchored on carbon nanocubes (denoted as VS4/CNTs) with a petal-shape structure consisting of nanolayers is successfully prepared through a one-step hydrothermal reaction. The influence of the optimal ratio of VS4 and CNTs on the electrochemical properties of VS4/CNTs composite is studied by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). The addition of CNTs increases the conductivity and relieves the volume expansion/contraction, resulting excellent electrochemical properties of VS4/CNTs. In the potential window of -1.4 V to 1.4 V, the VS4/CNTs composite electrode delivers an outstanding specific capacitance of 330 F g-1 (924 C g-1) at 1 A g-1, which is much higher than that of VS2 with 105 F g-1 (294 C g-1). The VS4/CNTs symmetric supercapacitor (SSC) device exhibits the areal capacitance as high as 676 mF cm-2 (1488 mC cm-2) at 0.5 mA cm-2, and the energy density of 4.55 W h m-2 (51.2 W h kg-1) at the power density of 2.75 W m-2 (30.95 W kg-1) within a large voltage up to 2.2 V. All the results confirm that VS4/CNTs composite with petal-shape structures is a promising material for high-performance energy storage devices.

Efficacy of Femtosecond Laser-Assisted Phacoemulsification for Cataract Patients and its Influence on Serum Levels of Inflammatory Factors.

OBJECTIVE: To investigate effect of femtosecond laser-assisted phacoemulsification in treating cataract patients, and to analyse its influence on serum inflammatory factors IL-6, IL-1ß, TNF-α . STUDY DESIGN: An analytical, descriptive study. PLACE AND DURATION OF STUDY: The Ophthalmologic Center, Rehabilitation Center Hospital of Gansu, China, from January 2016 to September 2017. METHODOLOGY: A total of 94 eyes were randomly divided into control group (47 cases) and observation group (47 cases). Control group was treated with traditional phacoemulsification. The observation group was added with femtosecond laser based on the treatment of the control group. Clinical efficacy of two groups was compared. RESULTS: Surgery time of the observation group was longer than that of the control group (p<0.001). Effective phacoemulsification time, cumulative dissipated energy, and liquid flow of the observation group were all less than those of the control group (all p<0.001). One day after surgery, aqueous flare and rate of corneal endothelium loss in the observation group were less than those of the control group (both p<0.001). Seven days after surgery, serum levels of IL-6, IL-1 and TNF- in the observation group were lower than those of the control group (all p<0.001). CONCLUSION: Femtosecond laser-assisted phacoemulsification has better clinical effect in treating cataract, and can reduce the energy and time cost in the phacoemulsification, decrease the serum levels of inflammatory factors and cause less postoperative complications. But it takes longer operation time and relatively higher treatment cost.

3D hierarchical porous V3O7·H2O nanobelts/CNT/reduced graphene oxide integrated composite with synergistic effect for supercapacitors with high capacitance and long cycling life.

V3O7·H2O possesses the merit of high specific capacitance, but weakness of cycling stability and low conductivity inhibit its application for energy devices, which requires the addition of carbon materials like carbon nanotubes (CNT) or graphene with properties of high conductivity and brilliant cycling stability to obtain high-performance composites. Since CNT or GO-based binary V3O7·H2O materials have been rarely studied with limited specific capacitance, we developed a novel, highly porous V3O7·H2O nanobelts/CNT/reduced graphene oxide (V3O7·H2O/CNT/rGO) ternary composite with a three-dimensional (3D) hierarchical micro-structure by a single step, facile hydrothermal process and self-assembly method with outstanding electrochemical performances. During the hydrothermal process, CNT-anchored V3O7·H2O nanobelts have been incorporated on the surface of rGO through in situ growth with preferred orientation, forming a 3D hierarchical porous structure composed mostly of mesopores and exhibiting enlarged specific surface area up to 53.7 m2·g-1. The well-designed V3O7·H2O nanobelts also display excellent adhesion with CNT/rGO, which leads to reduced resistance resulted from the synergistic effect of pseudocapacitors (V3O7·H2O nanobelts) and electric double-layer capacitors (EDLCs) (CNT/rGO) and large specific area with sufficient active sites ensure the composite to brilliant capacitive behavior. Applied to SCs, the ternary composite exhibits outstanding electrochemical performance with higher specific capacitance (685 F·g-1 at 0.5 A·g-1), higher energy density (34.3 W·h·kg-1) and extremely prominent cycle stability (99.7% of initial specific capacitance after 10,000 cycles) compared to those of most similar binary materials. Results suggest that the V3O7·H2O/CNT/rGO ternary composite is a promising candidate for electrode materials applying to high-performance supercapacitors.

A strategy for the synthesis of VN@C and VC@C core-shell composites with hierarchically porous structures and large specific surface areas for high performance symmetric supercapacitors.

A novel strategy for the fabrication of vanadium nitride (VN) and vanadium carbide (VC) encapsulated into amorphous carbon nanotube core-shell structured composites (denoted as VN@C and VC@C) was developed by the thermal treatment with H2V3O8@C core-shell composites under N2 and Ar atmospheres, respectively. The as-prepared VN@C and VC@C were comprised of core-shell structures with cores of crystalline VN particles and particles and shells of amorphous carbon nanotubes. There are some O elements remaining both in VN@C and VC@C. VN@C and VC@C exhibited hierarchically porous structures ranging from mesopores to macropores and high specific surface areas, which reached 222 and 164 m2 g-1, respectively. Symmetric supercapacitor (SSC) devices using VN@C and VC@C (denoted as VN@C SSC and VC@C SSC) were assembled and they showed good pseudocapacitive properties and were promising electrode materials for electrochemical capacitors. The VN@C SSC device exhibited better electrochemical performance including specific capacitance, areal energy density and cycling stability than the VC@C SSC device. The present findings revealed that VN@C and VC@C could be considered as potential materials for high-performance energy storage materials.

Hydrothermal encapsulation of VO2(A) nanorods in amorphous carbon by carbonization of glucose for energy storage devices.

In recent decades, tremendous attention has been paid to the development of new electrode materials with high capacitance to meet the requirements of electrode materials in supercapacitors. Among vanadium oxides, VO2(A) has recently received increasing attention due to its unique layered structure, phase transformation and applications in Li-ion batteries. However, few studies have focused on the electrochemical properties of VO2(A) as electrochemical capacitors. Herein, we develop a facile hydrothermal method to prepare VO2(A)@C core-shell structured composites by carbonization of glucose in the presence of V2O5 nanowires. The electrochemical properties of the VO2(A)@C core-shell composites are investigated as a supercapacitor electrode material for the first time; the composites show excellent pseudocapacitive behavior and display a specific capacitance as high as 179 F g-1 at 1 A g-1. A flexible asymmetric supercapacitor device is fabricated using VO2(A)@C composites and activated carbon and delivers an excellent capacitance of 0.5 F cm-2 at a scan rate of 5 mV s-1. Replacing the aqueous electrolyte with a LiCl/PVA gel electrolyte can efficiently improve the cycling performance to 85% retention after 1600 cycles. The good electrochemical performance of the composites indicates their high potential as electrode materials for supercapacitors.