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In-plane micro-supercapacitors (MSCs) possess higher volumetric energy density and are thus more compact compared with traditional aluminum electrolytic capacitors (AECs). As a result, developing in-plane MSCs with AC line filtering function is desired to replace the AECs and integrate with other electronic devices. Here, highly stretchable integrated system for in-plane MSCs with AC line filtering and UV detector were fabricated by designing buckled micro-electrodes based on SWCNT film and TiO 2 NPs. Although gel electrolyte was used in these MSCs, they still show an ultrafast frequency response with a phase angle of -75.2° because of their unique structure. Such MSCs thus can function as the AC line filtering devices. Furthermore, their AC line filtering behavior remains almost unchanged even stretched up to 200%. Further coating TiO 2 NPs on the buckled SWCNT micro-electrodes is able to endow the MSCs with another ability of UV photodetection with the sensitivity of 6.2. Importantly, such integrated device can still show stable photocurrent response and capacitance behaviors at different stretching times and even repeated stretching 100 times. The rational design of such stretchable integrated system for MSCs with AC line filtering and UV photodetector will pave the way for the applications in assembling supercapacitors and other electronics into highly stretchable integrated devices. [ABSTRACT FROM AUTHOR]

In this work, we put forward an effective approach by combining both highly transparent and conductive carbon nanotube (CNT) network and poly (3, 4-ethylene dioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) film to co-form-coordinate heterojunctions with silicon, and have developed a hybrid PEDOT:PSS-CNT/n-Si solar cell. The power conversion efficiency (PCE) of the as-designed solar cell can be improved up to 10.2%, which is much higher than the PCE values of both PEDOT:PSS/n-Si (5.5%) and CNT/n-Si (6.1%) solar cells fabricated using the same materials and process. PEDOT:PSS can fill the hundreds nanometer scale pores of the CNT network, both CNT network and PEDOT:PSS patches contact with the silicon concomitantly and form p Synergy -n heterojunctions through seamless contact with n-Si. The PEDOT:PSS-CNT composite film exhibits a much lower sheet resistance and remains high optical transmittance. Once the photo-generated holes are extracted to the PEDOT:PSS-CNT composite film, CNT network can serve as a carrier transport bridge, which is different from the design that inserts an ultrathin polymer between the CNT and Si. Incorporation of the continuous CNT network with PEDOT:PSS jointly in the as-designed simple and explicit structure has generated synergistic effects, which can make full use of the respective merits and then considerably enhance the PCE of hybrid PEDOT:PSS-CNT/n-Si solar cells. [ABSTRACT FROM AUTHOR]

Abstract: Background: Nonwoven single-walled nanotubes (SWNTs) are novel materials with a nanotopography macroscopic surface and pure-carbon composition, which may serve as coatings on implants in blood-contact environments. Methods: The adsorption behavior of albumin, fibrinogen, and fresh plasma on SWNT membranes was studied using scanning electron microscopy (SEM), energy-dispersive x-ray, and direct enzyme-linked immunosorbent assay, respectively. Platelet adhesion and activation were investigated in vitro using SEM observation, and via flow cytometry analysis by PAC-1, which binds to GPIIb/IIIa expressed on activated platelets. Results: Nonwoven SWNTs clearly displayed greater adsorption preference for fibrinogen than for albumin. However, adhered platelets were not observed by SEM. Results obtained from flow cytometry analysis further proved very low expression of GPIIb/IIIa on platelets caused by nonwoven SWNTs. Conclusion: The function of adsorbed fibrinogen to mediate platelet recognition, adhesion, activation, and aggregation was significantly suppressed, which induced extremely low levels of platelet adhesion and activation. [Copyright &y& Elsevier]

Branching structures in nanometer level are of great importance in developing nanoscale science and functional electrical devices. In this letter, multidimensional magnesium oxide structures with cone-shaped branching have been mass-produced using a simple chemical vapor deposition method. The dominant structures in the product include two-dimensional ‘+’, ‘T’, or ‘Γ’ assemblies, and three-dimensional complex configurations. The results presented here enrich the nanoscale community with new basic materials for the fabrication of functional electrical and chemical sensing devices. [Copyright &y& Elsevier]

In this Letter, we report the synthesis of cone-shaped 6H–SiC nanorods by an arc-discharge process. The axis of nanorods is preferentially along the 〈1 0 1¯ 0〉 direction. The diameters of the thin tips are about 10–30 nm, and the lengths range from tens of nanometers up to 1 μm. Branched nanostructures are also formed and the branches form 60° or 120° angles with the main nanorods. The formation of gradually enlarged Fe–Al–Si–C droplets and their high-enthalpy have led to the growth of cone-shaped hexagonal structure SiC nanorods by a VLS mechanism. [Copyright &y& Elsevier]

Constrained by the large mode loss, it is a challenge to achieve low threshold lasing in a thin nanowire whispering-gallery-mode (WGM) cavity at room temperature (RT). Here, we demonstrate low threshold single-mode polariton lasing at RT in a thin ZnO nanowire (165 nm in diameter) on Al 2 O 3 layer/rough Ag film. Such a structure can compensate the whispering-gallery mode loss and enhance the WGM polariton emission in UV region for subwavelength ZnO nanowires. They are attributed to the strong local electromagnetic field near nanowire induced by Ag film. The polariton lasing is confirmed by the low threshold, narrowing of the linewidth at threshold, nonlinear intensity-power dependence and continous blueshift of the emission. A clear transition from strong coupling regime to weak coupling regime is observed with increasing pump power. This work suggests low-cost and high-performance room-temperature nanolasers or polariton devices achieved in single thin ZnO nanowires. Low threshold single-mode polariton lasing is achieved at room temperature in a thin ZnO nanowire (165 nm in diameter) on 10 nm-Al 2 O 3 layer/100 nm-rough Ag film. Image 1 • The thinnest ZnO nanowire worked as a WGM nanocavity is 165 nm in diameter. • The formation of WGM polaritons has been efficiently promoted in subwavelength ZnO nanowires on 10 nm-Al 2 O 3 layer/100 nm-rough Ag film by LSPs. • The low threshold single-mode polariton lasing can be produced in a thin ZnO nanowire of 165 nm in diameter, in which the carrier screening effect may destroy the exciton-cavity photon strong coupling in this nanowire at high pump power. [ABSTRACT FROM AUTHOR]

The flexible zinc ion battery (ZIB) is deemed to be a promising candidate for flexible power supply due to its high security and low cost. However, conventional segregated battery configuration inevitably suffers from the relative displacement or detachment between two neighboring components at bending strain, which seriously degrade the performance of a flexible battery. Moreover, stubborn Zn dendrite drastically shortens the cycle life. Herein, by integrating Zn anode, zinc protective coating, polyamide separator and cathode into a single matrix, referred as the integrated electrode, a long cycle life and robust flexibility for ZIB in aqueous electrolyte are achieved. Seamless connection with the adjacent layers not only avoids the relative displacement or detachment caused by bending strain, but enhances the interfacial contact to promote the electrochemical kinetics. The built-in protective coating in the integrated configuration significantly inhibits the dendrites and side reactions for extending the durability. Furthermore, the integrated configuration makes the whole battery lighter, thinner and more powerful. Therefore, this work provides a new design idea for engineering innovative battery configuration and enables high performances for a flexible ZIB. Meanwhile, the research results would deliver great potential applications in flexible electronics and boost the development of configuration of energy storage devices. An ingenious configuration with robust interfacial contact is developed via the integration of Zn anode, zinc protective coating, polyamide separator and cathode into a single matrix, enabling the high flexibility and the dendrite-free boosted durability for zinc ion batteries. Image 1 • A flexible and durable zinc ion battery with integrated configuration is developed by manageable and scaleable process. • Continuous seamless connection prevents the displacement or detachment and ensures the steady electron transfer. • The built-in Zn anode protective coating inhibits dendrite growth and tightly glues the anode and polyamide separator. • The integrated configuration delivers significantly prolonged lifespan, reduced overpotential and boosted flexibility. [ABSTRACT FROM AUTHOR]

Chirality separation of single-wall carbon nanotubes (SWCNTs) is key to enabling applications in single photon sources, optoelectronic devices and bioimaging, and it generally requires multiple separation steps to obtain single chirality species with the desired purity. In this work, we report the use of a novel sodium hyodeoxycholate (SHC) surfactant for separation of single-chirality SWCNTs. The results demonstrated that chirality-selective adsorption and desorption of SWCNTs on a gel column can be achieved readily by modulating the concentrations of the SHC-based mixed surfactants. Through an optimized one-step procedure, single-chirality (6,5) SWCNTs were successfully separated, and the chirality purity was estimated to be 97% by using a spectroscopic approach, exceeding most reported purities for traditional surfactant-based one- or multiple-step separations. Due to the ultrahigh chirality resolution of the present method, the (6,5) SWCNTs can also be effectively separated from different SWCNT materials with various diameter or chirality distributions, even from materials containing very few (6,5) SWCNTs. The high-purity chirality separation demonstrated in this work lays an important foundation for the industrial production and applications of single-chirality SWCNTs. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Using the carbon nanotube (CNT) arrays embedded in anodic aluminum oxide (AAO) template as an electrode, large amounts of Ni nanoparticles have been encapsulated into the CNTs by an alternating current (AC) electrodepostion technique. As deposited Ni nanoparticles with a typical size of 50–60 nm randomly nucleated on the CNT walls, thus inhomogeneously distributed in the CNTs. After annealing at 600 ∘C, the nanoparticles transformed into quasi-spherical structures with the diameter increasing to 60–80 nm. The quasi-spherical nanoparticles were aligned in orderly rows along the axis of the CNT channels. Magnetic hysteresis measured at 5 K showed that the coercivity was 450 Oe for the as-deposited sample and 385 Oe for annealed sample, with the applied magnetic field parallel with the CNT’s axis. The structures and magnetic properties were discussed for both as-deposited and annealed samples. [Copyright &y& Elsevier]

Abstract: A new type of flower-like ZnO nanostructure was prepared on a large scale through a very simple solvothermal method. The nanoflowers are assembled by many thin and uniform hexagonal-structured ZnO nanosheets, with a thickness of around 6nm. The growth mechanism of the nanoflowers is discussed based on the reaction conditions. Room-temperature optical measurements reveal that such ZnO nanoflowers have very strong UV bandedge emission with a large Stokes shift and an asymmetrical band profile. This luminescence characteristic may be attributed to the anisotropic energy band structure of the quantum-confined ZnO nanosheets. [Copyright &y& Elsevier]

We report an innovative method for the fast preparation of wafer-scale uniform single-wall carbon nanotubes (SWCNT) films with controllable density by NaHCO 3 tuning the interaction between amine-functionalized substrates and surfactant-dispersing SWCNTs in aqueous solution. With this technique, a 4-inch SWCNT film with a linear density of ∼30 tubes/μm can be achieved in 1 s, and over 60 tubes/μm within 30 s using a high-concentration SWCNT solution. The SWCNT density changes by less than 8% over a 4-inch area. The electrical uniformity of the as-prepared wafer-scale single-chirality SWCNT film was demonstrated to be within 10.8% for subthreshold swing and 12% for carrier mobility and 13.5% for their on-current, which is the most uniform SWCNT films reported so far fabricated from the surfactant-dispersed SWCNT solution. Further, the photodetectors made by the uniform semiconducting SWCNT films exhibit excellent cascading ability, which linearly amplify the output photovoltages and could produce a photovoltage responsivity of 2.5 × 106 V/W. When three-stage cascading photodetectors are used as optical gate to establish an integrated photoelectric system, a 20-mW/cm2 light illumination produces the current responsivity of 147.3 A/W under a source/drain voltage of −0.1 V. Our present technique lays an important foundation for their applications in integrated circuits. Image 1 [ABSTRACT FROM AUTHOR]

The free-standing Si-coated carbon nanofiber (Si/CNF) mat was fabricated for the anode of lithium ion battery through combining electrospun CNF mat with electrodeposited Si layer. Spaghetti or granule-like Si was obtained by varying the deposition conditions. This Si/CNF mat was directly used as an active material and a current collector as well, which involves neither binders nor additional metal substrate. The best performance was achieved in spaghetti-like Si due to its highly porous nature which can accommodate volume expansion and large surface area which benefit the efficient charge transfer both at Si/CNF interface and at the electrode/electrolyte interface. The optimized Si/CNF mat after annealing at 1000 °C delivered a capacity of 870 mA h g −1 at 1st discharge and 730 mA h g −1 at 50th discharge with a capacity retention of 84%, improving the capacity of pure CNF (280 mA h g −1 at the 50th discharge) by almost three times. In addition, corrosion of the current collector no longer exists in our approach. Our X-ray photoemission spectroscopy and electrochemical analysis revealed that the formation of Si–C bond through high temperature annealing can enhance the adhesion between silicon and carbon at the interface which benefits the cyclic performance of anode ultimately. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotube (CNT) fibers are a novel type of fibrous materials that show potential in polymeric composite fields. In this study, we investigated the interfacial behavior of a single single-walled carbon nanotube (SWCNT) fiber embedded in isotactic polypropylene (iPP) matrix. The SWCNT fibers were found to be able to act as a heterogeneous nucleating agent which inducing the formation of transcrystals around the fiber surface. According to the theory of heterogeneous nucleation, the interfacial free energy difference Δσ of iPP on the SWCNT fibers was determined and compared with that on the conventional fibers. By carefully controlling the crystallizing conditions, three types of α-iPP supra-molecular microstructures with different optical birefringences were obtained. Raman spectra were utilized to investigate the influences of the supra-molecular microstructures of the transcrystalline (tc) layer on the strain transfer efficiency from the matrix to the fibers at a microscopic level. Conventional single-fiber pull-out tests were further employed to compare with the results derived from the Raman tests. [Copyright &y& Elsevier]

Abstract: Heterostructures of side-to-side biaxial ZnS/Zn2SnO4 (ZTO) nanowires have been fabricated via a simple one-step thermal evaporation process. Structural characterization by high-resolution transmission electron microscopy and electron diffraction indicates that both the face-centered cubic spinel ZTO subsection and the wurtzite ZnS subsection of the heterostructure are well crystallized with a distinct interface along the heterostructure axial direction. Based on detailed analysis of the growth process of biaxial ZnS/ZTO nanowire heterostructures, there are two dominating stages: a vapor–liquid–solid (VLS) controlled growth of ZTO sub-nanowire and a self-assembly growth of ZnS sub-nanowire onto the preformed ZTO base nanowire. A growth model of the heterostructures is proposed. The presented method would be flexible and feasible for the synthesis of other nano-heterostructures with non-oxide/oxide interface to meet the growing demands of nanoscale science and technology. [Copyright &y& Elsevier]

Abstract: We applied X-ray absorption near edge structure (XANES) spectroscopy to investigate the adsorption of proteins onto single-walled carbon nanotubes (SWCNTs). Specific XANES spectral features such as peptide Cn proteins were recognized and found to be affected by the corresponding aromatic structure of SWCNTs. Experimental data combined with first-principle calculation of the investigated nano-complex allow the understanding of adsorption mechanism and reveal that an interface interaction occurs leading to precise structural distortions of proteins. The study also demonstrates that XANES is a powerful tool to characterize structural details of proteins at the interface of complex systems. [Copyright &y& Elsevier]

Abstract: PbTiO3 nanotube arrays have been synthesized via sol–gel template method, and their morphology and structures have been determined by scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The diameter and length of these nanotubes are about 300nm and 50μm, respectively, and their wall thickness is typically several tens of nanometers. XRD data shows that as-prepared PTO nanotubes possess perovskite structure, and electron diffraction demonstrates that they are polycrystalline. Photoluminescence spectrum of PTO nanotubes reveals an intense and wide emission band centered at 505nm. Polarization–electric field (P–E) response curves of PTO nanotube array were measured, and the hysteresis loops illustrate a room temperature ferroelectric characteristic of as-prepared PTO nanotubes. [Copyright &y& Elsevier]

Abstract: Many applications based on single-walled carbon nanotubes (SWNTs) require chemical modification of carbon nanotube to optimize the functionalities of the device. In this contribution we discuss the properties of SWNTs immersed in a hydrobromic acid (HBr) solution. Changes of atomic and electronic structures of bromine modified SWNTs were investigated using photoelectron spectroscopy (PES). Spectra of SWNTs before and after immersion in the HBr solution exhibit different features. To understand the mechanism of interaction between SWNTs and bromine, we performed density-functional theory calculations to reveal the structural changes, adsorption energy and chemical bonding information of SWNTs interacting with bromine. In addition, based on the Gelius model, from the molecular orbitals (MOs), we calculated ultraviolet photoelectron spectra (UPS) of SWNTs with and without functionalizing and compared them with the experiment. The present study is a first step in the understanding of the functionalization mechanism of carbon nanotubes. [Copyright &y& Elsevier]

Abstract: Structural defects play an important role in the physics of carbon nanototube. However, very few investigations of the structural changes induced by purifying process and other treatments have been performed by means of X-ray absorption near-edge structure (XANES) spectroscopy. We used XANES spectroscopy to detect the presence of defects induced in single-walled carbon nanotubes (SWNTs) by nitric acid treated processes and by an Ar+ ion bombardment. The relationship between the features in XANES spectrum and the structural defects has been discussed systematically. Data also addresses evidence of oxygen effect induced by aging on nanotubes. [Copyright &y& Elsevier]

Abstract: Water molecules adsorbed on a double-walled carbon nanotube (DWCNT) serve as charge trapping centers when present in low density and as electron donors when present in high density. There is a discontinuous change between the low- and high-density regions. H2O molecules are apt to be adsorbed on the outer surface of DWCNTs, and in this case the electrical transport properties are extremely sensitive to environment, which suggests that DWCNTs are hole doped and act as an electric dipole with the inner tube. [Copyright &y& Elsevier]

Abstract: By investigating the morphologies and microstructures of the cathode deposits prepared by self-sustained arc discharge between graphite rods, we consider that there are two electron emission mechanisms occurring on the cathode: field emission and thermionic emission. The former occurs mainly on the edge of the growing surface, by which we can explain the formation of the outer hard shell of the cathode deposit; while the latter occurs mainly on the growing surface except for the edge area and it is the main cause for the growth of carbon nanotubes. [Copyright &y& Elsevier]

Abstract: Wurtzite InN nanobelts have been synthesized in bulk quantities by means of in situ nitriding indium oxide powders in ammonia flux, with a high yield, high purity and good reproducibility. As-synthesized InN nanobelts have typical widths of 1–5μm, thickness of 40–50nm and lengths of tens to hundreds of microns imaged by scanning electron microscopy. Transmission electron microscopy reveals that the synthesized InN nanobelts are single crystalline in [0001] orientation and preferentially enclosed by top surfaces /side surfaces . Photoluminescence spectrum of InN nanobelts at room temperature shows a strong emission peak centered at 704nm (1.76eV). [Copyright &y& Elsevier]