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Transition metal nitrides (TMNs) are promising electrode materials for high-performance energy storage devices owing to their excellent conductivity, thermal stability, high theoretical capacity and excellent electrochemical activity. However, the structural instability present in the electrochemical reaction process significantly limits their widespread application. Herein, we present a V–Ni-based nitride heterojunction on carbon cloth (VN/Ni3N–Ni/CC) as an active electrode material for flexible supercapacitors. The VN/Ni3N–Ni/CC composite electrode was successfully fabricated through controllable nitridation of the corresponding vanadium–nickel oxide grown on carbon cloth (V–Ni–O/CC) precursors. The electrochemical results reveal that the areal capacitance of the VN/Ni3N–Ni/CC based supercapacitor with a nitriding temperature of 400 °C and a nitriding time of two hours can achieve a maximum areal capacitance of 845.63 mF cm−2 at a current density of 0.5 mA cm−2, and the electrode in the three-electrode system retains 86.1% of its initial capacitance value after 1500 cycles at a current density of 10 mA cm−2. In addition, the assembled flexible all-solid-state symmetric supercapacitor using the VN/Ni3N–Ni/CC electrode exhibits an areal capacitance ratio of 19.1 mF cm−2 at a current density of 0.4 mA cm−2 and excellent cycling stability. Moreover, it displays exceptional flexibility under different bending angles highlighting its potential for integration into flexible electronic devices. [ABSTRACT FROM AUTHOR]

High energy density and enhanced rate capability are highly sought-after for supercapacitors in today's mobile world. In this work, polyaniline/titanium carbide (MXene) (PANI/Ti3C2Tx) nanohybrid is synthesized through a facile and cost-effective self-assembly of one-dimensional (1D) PANI nanofibers and two-dimensional (2D) Ti3C2Tx nanosheets. PANI/Ti3C2Tx delivers greatly improved specific capacitance, ultrahigh rate capability (67% capacitance retention from 1 to 100 A·g−1) as well as good cycle stability. Electrochemical kinetic analysis reveals that PANI/Ti3C2Tx is featured with surface capacitance-dominated process and has a quasi-reversible kinetics at high scan rates, giving rise to an ultrahigh rate capability. By using PANI/Ti3C2Tx as positive electrode, an 1.8 V aqueous asymmetric supercapacitor (ASC) is successfully assembled, showing a maximum energy density of 50.8 Wh·kg−1 (at 0.9 kW·kg−1) and a power density of 18 kW·kg−1 (at 26 Wh·kg−1). Moreover, an 3.0 V organic ASC is also elaborately fabricated by using PANI/Ti3C2Tx, achieving an ultrahigh energy density of 67.2 Wh·kg−1 (at 1.5 kW·kg−1) and a power density of 30 kW·kg−1 (at 26.8 Wh·kg−1). The present work not only improves fundamental understanding of the structure-property relationship towards ultrahigh rate capability electrode materials, but also provides valuable guideline for the rational design of high-performance energy storage devices with both high energy and power densities. [ABSTRACT FROM AUTHOR]

The three-dimensional (3D) porous network structure self-assembled from birnessite-type MnO2 flakes and the urchin-like structure composed of MnO2 nanotubes were fabricated by a convenient one-step hydrothermal method by changing the amount of HCl as the sulfur scaffold for lithium–sulfur batteries. The perfect 3D interconnected nanostructure as a sulfur host displayed excellent electrochemical performance compared to the MnO2 tubes. Benefiting from the well-interconnected 3D spherical architecture, the MnO2/S cathode can reach a high specific capacity of 1582.9 mA h g−1 at 0.1C and a preferable cycling stability with excellent Coulombic efficiency. The porous 3D architecture and the interaction of the Mn–S chemical bond can not only facilitate electron transport, lithium diffusion, and relieve the volume expansion of S but can also effectively restrict the shuttling effect of soluble polysulfides generated during the charge–discharge process. [ABSTRACT FROM AUTHOR]

Graphene/CoO nanocomposites with different morphologies were fabricated by hydrothermal method. The morphology of nanocomposites was characterized by scanning electron microscopy. These composites could be used as the electrode materials for supercapacitors. The eletrochemical behavior of the composite was tested by cyclic voltammetry and galvanostatic charge-discharge measurements in 1.0 mol/L KOH solution. The results showed that the graphene/CoO nanopetal composite exhibited excellent electrochemical performance. The specific capacitance value could reach up to 714 F/g at a scan rate of 2 mV/s. Besides, the capacitance of the graphene/CoO nanopetal composite was 841 F/g at a current density of 0.1 A/g. After galvanostatic charge-discharge 1000 laps at the current density of 0.4 A/g, the specific capacitance could keep 96.7% of original capacitive value, demonstrating its good cycling stability. Graphical Abstract: [ABSTRACT FROM AUTHOR]

The S-doped mesoporous nanocomposite (S-TNT) of HTiNbO5 nanosheets (NSs) and anatase TiO2 nanoparticles (NPs) with exposed {101} facets has been successfully synthesized by first mixing freeze-dried HTiNbO5 NSs with titanium isopropoxide and then calcination with thiourea in air. The exposed anatase {101} facets can act as a possible reservoir of the photogenerated electrons, yielding a highly reactive surface for the reduction of O2 to O2Ṗ−. The partial substitution of Ti4+ by S6+ in the lattice of TiO2 NPs leads to a charge imbalance in S-TNT and the formation of Ti–O–S bonds. As a result, the formed cationic S-TNT favours adsorption of hydroxide ions (OH−ads) and thus captures the photo-induced holes to form hydroxyl radicals (ṖOH). Moreover, with the formation of Ti–O–S bonds, partial electrons can be transferred from S to O atoms and hence the electron-deficient S atoms might capture photo-induced electrons. The surface-adsorbed SO42− could also act as an efficient electron trapping center to promote the separation of charge carriers. In addition, the Ti3+ species due to the removal of oxygen atoms during calcination and the associated oxygen vacancy defects on the surface of S-TNT could act as hole and electron scavengers, respectively. Besides, the closely contacted interface is formed between HTiNbO5 NSs and anatase TiO2 NPs due to the common features of TiO6 octahedra in two components, resulting in a nanoscale heterojunction structure to speed up the separation rate of photogenerated charge carriers. The formation of a nano-heterojunction and the incorporation of Ti3+ and S dopants give rise to the visible and near-infrared light response of S-TNT. The combined effects greatly retard the charge recombination and improve the photocatalytic activity for the degradation of rhodamine B (RhB) and phenol solution under visible light irradiation. The corresponding photocatalytic mechanism was investigated via the active species capture experiments. The present work may provide an insight into the fabrication of delicate composite photocatalysts with excellent performance. [ABSTRACT FROM AUTHOR]

Graphene–polyaniline (PANI) nanocomposites with different morphologies were successfully fabricated by an effective one-step hydrothermal method. The morphologies of PANI could be controlled from nanowires to nanocones by adjusting the amount of aniline with the assistance of an ultrasonication process. By taking the advantages of the high conductivity of graphene and the pseudocapacitance of PANI, graphene–PANI composites were used as an example for the application to the supercapacitor electrode materials. The cyclic voltammograms (CV) and galvanostatic charge–discharge measurements demonstrate that the graphene–PANI shows excellent electrochemical properties. The graphene–PANI nanowire composite (724.6 F g−1) exhibited higher specific capacitance than that of the graphene–PANI nanocone composite (602.5 F g−1) at a current density of 1.0 A g−1. Furthermore, the graphene–PANI nanowire composite exhibited outstanding capacitive performance with a high specific capacitance of 957.1 F g−1 at 2 mV s−1 and a high cycle reversibility of 90% after charge–discharge 1000 cycles. The improved electrochemical properties of the graphene–PANI nanocomposites suggest their promising applications to high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

MnO2/graphene nanocomposites with different morphologies were synthesized and the petal-shaped nanosheet MnO2/graphene composite was developed as an electrode material for nonenzymatic hydrogen peroxide (H2O2) sensor. The morphology, structure, composition, and hydrophilicity of the resulting products were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and the contact angle tests. In addition, the fabricated MnO2/graphene composites could be used as catalysts for the electrochemical oxidation of H2O2. Cyclic voltammogram (CV) experiments indicated that MnO2/graphene-modified electrode showed good electrocatalytic activity towards both the oxidation and reduction of H2O2 in a neutral environment. Amperometric response results illustrated that this nonenzymatic sensor had excellent anti-interference ability and displayed two linear ranges from 10 to 90 µM and from 0.2 to 0.9 mM with a detection limit of 2 µM. [ABSTRACT FROM AUTHOR]

Novel MnO2 petal nanosheet and nanorod/graphene composites are successfully fabricated by a facile one-step hydrothermal method through changing the content of the Mn source. The formation mechanism of different morphologies of MnO2/graphene composites have been studied. The structure of the MnO2/graphene is “sandwich”-like, with MnO2 petal nanosheets and nanorods homogeneously anchored on each side of the graphene. Furthermore, the MnO2/graphene composites with different shapes can be used for supercapacitor electrode materials. The experimental results show that the MnO2 petal nanosheet/graphene composite has better capacitance performance than that of the MnO2 nanorod/graphene composite. The MnO2 petal nanosheet/graphene composite shows excellent specific capacitance as high as 516.8 F g−1 at a scan rate of 1 mV s−1 in 1 M Na2SO4 electrolyte and good long-term cycle stability, indicating its potential application to act as a promising electrode material for high-performance supercapacitors. This study provides a facile and in situ method to prepare metal oxide/graphene composite materials and a novel scaffold to construct other metal oxides with graphene for energy storage. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) nanotubes with improved electrochemical activity were synthesized by using a self-degradable MnO2 template and were developed as electrode materials for biosensors. The morphology, composition, and optical properties of the resulting products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), and cyclic voltammetry (CV). The results confirmed that the obtained PANI nanotubes had a perfect tubular structure with uniform diameters and lengths. Furthermore, PANI nanotubes were immobilized onto the surface of a glassy carbon electrode (GCE) and applied to construct a sensor. The obtained PANI-modified GCE showed high catalytic activity in the electrochemical oxidation of dopamine (DA) in a near neutral environment. Differential pulse voltammogram (DPV) results illustrated that the fabricated DA biosensor had high anti-interference ability towards uric acid (UA), ascorbic acid (AA), and glucose (GC). In addition, the fabricated biosensor showed superior performance with two wide linear ranges from 7 × 10−5 to 3 × 10−4 M and 3 × 10−4 to 5 × 10−3 M with a lower limit of detection of 0.5 × 10−9 M. [ABSTRACT FROM AUTHOR]

A ternary nanocomposite of graphene/polyaniline (PANI)/porous silica MCM-41 (MCM-41) was prepared by a hydrothermal method. The amount of graphene oxide (GO) in the graphene/PANI/MCM-41 nanocomposite had a strong effect on the supercapacitor performance. The experimental results showed that the specific capacitance of the graphene/PANI/MCM-41 nanocomposite could reach the highest value when the GO content was 50%. The specific capacitance of the nanocomposite was 405 F g−1 at a current density of 0.8 A g−1. Furthermore, over 91.4% of the original capacitance was retained after repeating the galvanostatic charge–discharge for 1000 cycles. The performance of the prepared supercapacitor containing different amounts of GO were studied in detail. [ABSTRACT FROM AUTHOR]

In neurons, a highly regulated microtubule cytoskeleton is essential for many cellular functions. These include axonal transport, regional specialization and synaptic function. Given the critical roles of microtubule-associated proteins (MAPs) in maintaining and regulating microtubule stability and dynamics, we sought to understand how this regulation is achieved. Here, we identify a novel LisH/WD40 repeat protein, tentatively named nemitin (neuronal enriched MAP interacting protein), as a potential regulator of MAP8-associated microtubule function. Based on expression at both the mRNA and protein levels, nemitin is enriched in the nervous system. Its protein expression is detected as early as embryonic day 11 and continues through adulthood. Interestingly, when expressed in non-neuronal cells, nemitin displays a diffuse pattern with puncta, although at the ultrastructural level it localizes along the microtubule network in vivo in sciatic nerves. These results suggest that the association of nemitin to microtubules may require an intermediary protein. Indeed, co-expression of nemitin with microtubule-associated protein 8 (MAP8) results in nemitin losing its diffuse pattern, instead decorating microtubules uniformly along with MAP8. Together, these results imply that nemitin may play an important role in regulating the neuronal cytoskeleton through an interaction with MAP8. [ABSTRACT FROM AUTHOR]

The Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway is active in both normal hematopoiesis and hematological malignancies. Moreover, Janus kinase-2 (JAK2) is the key hematopoietic kinase, and mutations together with single nucleotide polymorphisms (SNPs) of JAK2 have been thoroughly evaluated. In this study, we aimed to investigate whether the synonymous genetic polymorphism A830G in the JAK2 gene is associated with the treatment outcomes of Ara-C-based chemotherapy regimens in patients with acute myeloid leukemia (AML). A total of 152 patients with AML in a Chinese population were enrolled in our study. Peripheral blood samples drawn at the time of diagnosis were analyzed for the presence of JAK2 A830G by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS). The results showed that frequencies of the AA genotype were higher in the group 40–60 years old, higher white blood cell (WBC) patient group, homoharringtonine and Ara-C (HA) regimen group, and good therapy response group, and patients with the GG genotype were significantly associated with a higher rate of early death. We conclude that the AA and GG genotypes of JAK2 A830G might be important markers for therapy outcomes of patients with AML in a Chinese population. [ABSTRACT FROM AUTHOR]