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Aqueous rechargeable Ni‐Fe batteries featuring an ultra‐flat discharge plateau, low cost, and outstanding safety characteristics show promising prospects for application in wearable energy storage. In particular, fiber‐shaped Ni‐Fe batteries will enable textile‐based energy supply for wearable electronics. However, the development of fiber‐shaped Ni‐Fe batteries is currently challenged by the performance of fibrous Fe‐based anode materials. In this context, this study describes the fabrication of sulfur‐doped Fe2O3 nanowire arrays (S‐Fe2O3 NWAs) grown on carbon nanotube fibers (CNTFs) as an innovative anode material (S‐Fe2O3 NWAs/CNTF). Encouragingly, first‐principle calculations reveal that S‐doping in Fe2O3 can dramatically reduce the band gap from 2.34 to 1.18 eV and thus enhance electronic conductivity. The novel developed S‐Fe2O3 NWAs/CNTF electrode is further demonstrated to deliver a very high capacity of 0.81 mAh cm−2 at 4 mA cm−2. This value is almost sixfold higher than that of the pristine Fe2O3 NWAs/CNTF electrode. When a cathode containing zinc‐nickel‐cobalt oxide (ZNCO)@Ni(OH)2 NWAs heterostructures is used, 0.46 mAh cm−2 capacity and 67.32 mWh cm−3 energy density are obtained for quasi‐solid‐state fiber‐shaped NiCo‐Fe batteries, which outperform most state‐of‐the‐art fiber‐shaped aqueous rechargeable batteries. These findings offer an innovative and feasible route to design high‐performance Fe‐based anodes and may inspire new development for the next‐generation wearable Ni‐Fe batteries. [ABSTRACT FROM AUTHOR]

In recent years, two‐dimensional (2D) ternary materials have attracted wide attention due to their novel properties which can be achieved by regulating their chemical composition with a very great degree of freedom and adjustable space. However, as for the precise synthesis of 2D ternary materials, great challenges still lie ahead that hinder their further development. In this work, we demonstrated a simple and reliable approach to synthesize 2D ternary‐layered BiOCl crystals through a microwave‐assisted space‐confined process in a short time (<3 minutes). Their ultraviolet (UV) detection performance was analyzed systematically. The photodetectors based on the as‐obtained BiOCl platelets demonstrate high sensitivity to 266‐nm laser illumination. The responsivity is calculated to be ∼8 A/W and the response time is up to be ∼18 ps. On the other hand, the device is quite stable after being exposed in the ambient air within 3 weeks and the response is almost unchanged during the measurement. The facile and fast synthesis of single crystalline BiOCl platelets and its high sensitivity to UV light irradiation indicate the potential optoelectronic applications of 2D BiOCl photodetectors. [ABSTRACT FROM AUTHOR]

This study investigated the adsorption of particulate matter with a diameter <2.5 µm (PM2.5) by leaves of ten tree species in Shenyang city. An aerosol generator was used to quantitatively determine PM2.5 adsorption capacity. Atomic force microscopy was used to determine the micro-morphological characteristics of the leaf surface, including roughness parameters and the PM2.5 absorption mechanism of the tree leaves. The results showed a positive correlation between PM2.5 adsorption capacity and PM2.5 concentration during different months: October (0.618 ± 0.16 μg· cm−2) > September (0.514 ± 0.14 μg· cm−2) > July (0.509 ± 0.14 μg· cm−2) > August (0.487 ± 0.12 μg· cm−2) > June (0.464 ± 0.08 μg· cm−2) > May (0.359 ± 0.08 μg· cm−2). PM2.5 absorption capacity was higher on leaves where the folded leaf lamina was covered by fine hairs, as they were rough with many protrusions and fillisters on the leaf surface. The tree species with a smooth leaf surface and low stomatal density and stomatal opening had a weak ability to adsorb PM2.5. The average roughness of the leaves was ranked according to PM2.5 adsorption per unit leaf area, and leaf roughness was significantly correlated with PM2.5 adsorption capacity per unit leaf area (R2 = 0.706). Tree species with a leaf surface morphology that facilitates absorption of PM2.5 and other particles, such as Pinus tabulaeformis and Platycladus orientalis, should be selected to improve the environmental effects of urban forest on air quality. [ABSTRACT FROM AUTHOR]

Abstract: The charge transfer between molecules and materials can modulate the polarizability tensor of the molecules and lead to an enhancement of the Raman scattering. Surface‐enhanced Raman scattering on in‐plane anisotropic layered materials has suggested the crystalline‐axis‐dependent charge interactions between molecules and materials. However, the full understanding of the anisotropic charge transfer process is still lacking. The rigorous anisotropic nature and structural diversity of single‐walled carbon nanotube (SWNT) provide an ideal platform to systematically study the anisotropic charge transfer process. The present work reports the anisotropic Raman enhancement effect of molecules on horizontally aligned SWNT arrays and attribute it to the charge transfer efficiency that depends on the laser polarization direction and the resonance of SWNTs. The Raman signal of probe molecules on SWNT arrays is enhanced and reaches the maximum intensity when the incident laser is polarized along the SWNT axial direction, and the intensity is the minimum if they are perpendicular to each other. The different efficiencies of charge transfer are further confirmed by polarized optical absorption measurements and the energy alignment analysis. The present work provides a sensitive way to study the tunable charge interactions between molecules and anisotropic low‐dimensional materials, which are also important for polarization‐controlled optoelectronic applications. [ABSTRACT FROM AUTHOR]

For the application of single-walledcarbon nanotubes (SWNTs) in nanoelectronic devices, techniques toobtain horizontally aligned semiconducting SWNTs (s-SWNTs) with higherdensities are still in their infancy. We reported herein a rationalapproach for the preferential growth of densely packed and well-aligneds-SWNTs arrays using oxygen-deficient TiO2nanoparticlesas catalysts. Using this approach, a suitable concentration of oxygenvacancies in TiO2nanoparticles could form by optimizingthe flow rate of hydrogen and carbon sources during the process ofSWNT growth, and then horizontally aligned SWNTs with the densityof ∼10 tubes/μm and the s-SWNT percentage above 95% weresuccessfully obtained on ST-cut quartz substrates. Theoretical calculationsindicated that TiO2nanoparticles with a certain concentrationof oxygen vacancies have a lower formation energy between s-SWNT thanmetallic SWNT (m-SWNT), thus realizing the preferential growth ofs-SWNT arrays. Furthermore, this method can also be extended to othersemiconductor oxide nanoparticles (i.e., ZnO, ZrO2andCr2O3) for the selective growth of s-SWNTs,showing clear potential to the future applications in nanoelectronics. [ABSTRACT FROM AUTHOR]

The emergence of 2D van der Waals (vdW) materials, owing to highly tunable electrical conductivity, remarkably free stackability, and excellent compatibility for heterojunction integration, has provided abundant research diversity of artificial synapses. Here, an innovative 2D vdW heterosynaptic memtransistor (vdW‐HT) synapse is proposed with a ferroelectric CuInP2S6 inserted layer. Neuromorphic synaptic weight change of the vdW‐HT synapse in this work are modulated by the synergistic effects of interlayer coupling and ferroelectric polarization reversal. It is the first time to evaluate the required initial energy consumption of ferroelectric vdW‐HT synapses with matrixed biomimetic characteristics of “Learning–Forgetting–Re‐learning–Memorizing.” The required initial energy consumption is only ≈3.06 pJ, which provided supporting evidence to indicate the promising potential of vdW‐HT synapses in exploring neuromorphic applications. A vdW‐HT computing system with artificial recognition capability for intelligent automobiles is established and demonstrated outstanding recognition abilities for multiple targets in various environments. The highest recognition accuracy for pedestrians is 98%. In addition, the excellent recognition property is integrated with a robotic arm, successfully achieving high‐precision grasping behavior and designated position transmission for identified targets. These results provide promising strategies for the integrated development of emerging neuromorphic electronics and industrial applications. [ABSTRACT FROM AUTHOR]

Sample suspension is a valuable method to improve the mechanical, thermal, electronic, and optical properties of low-dimensional materials. In terms of confined light-matter waves—the polaritons, sample suspension can elongate the wavelength of polaritons with a positive phase velocity. Previous work demonstrates a wavelength elongation of ∼10% for hyperbolic phonon polaritons (HPPs) in uniaxial crystals of hexagonal boron nitride (hBN). In this work, we report the alteration of HPPs in biaxial α-phase molybdenum trioxide (α-MoO3) by sample suspension. Our combined infrared nano-imaging experiments and electromagnetic theory reveal a wavelength elongation > 60% and a propagation length increase > 140%, due to the simultaneous wavelength elongation and dissipation elimination in the suspended specimen. We have also examined HPPs in α-MoO3 with a negative phase velocity. The sample suspension shortens the HPP wavelength and simultaneously reduces the dissipation due to the unique permittivity tensor. The HPPs with improved figures of merits in the suspended specimen may be developed for nano-polaritonic circuits, biochemical sensing, emission engineering, and energy transfer. [ABSTRACT FROM AUTHOR]

Rechargeable lithium-ion batteries are integral to contemporary energy storage, yet current anode material systems struggle to meet the increasing demand for extended range capabilities. This work introduces a novel composite anode material composed of one-dimensional 2H-phase tin disulfide (SnS 2 ) nanoribbons enclosed within cavities of single-walled carbon nanotubes (SnS 2 @SWCNTs), achieved through precise atomic engineering. Employing aberration-corrected transmission electron microscopy, we precisely elucidated the crystal structure of SnS 2 within the confines of the SWCNTs. This deliberate design effectively addresses the inherent limitations of SnS 2 as a lithium-ion anode material, including its low electrical conductivity, considerable volume expansion effects, and unstable solid electrolyte interface membrane. Testing confirmed that SnS 2 transforms into the Li 5 Sn 2 alloy phase after full lithiation and back to SnS 2 after delithiation, showing excellent reversibility. The composite also benefits from edge effects, improving lithium storage through stronger binding and lower migration barriers, which were supported by calculations. This pioneering work advances high-performance anode materials for applications.

Acquiring a deep insight into the electron transfer mechanism and applications of one-dimensional (1D) van der Waals heterostructures (vdWHs) has always been a significant challenge. Herein, through direct observation using aberration-corrected transmission electron microscopy (AC-TEM), we verify the stable formation of a high-quality 1D heterostructure composed of PbI 2 @single-walled carbon nanotubes (SWCNTs). The phenomenon of electron transfer between PbI 2 and SWCNT is elucidated through spectroscopic investigations, including Raman and X-ray photoelectron spectroscopy (XPS). Electrochemical testing indicates the electron transfer and enduring stability of 1D PbI 2 within SWCNTs. Moreover, leveraging the aforementioned electron transfer mechanism, we engineer self-powered photodetectors that exhibit exceptional photocurrent and a 3-order-of-magnitude switching ratio. Subsequently, we reveal its unique electron transfer behavior using Kelvin probe force microscopic (KPFM) tests. According to KPFM, the average surface potential of SWCNTs decreases by 80.6 mV after filling. Theoretical calculations illustrate a charge transfer of 0.02 e per unit cell. This work provides an effective strategy for the in-depth investigation and application of electron transfer in 1D vdWHs.

Piezoelectric nanogenerators (PENGs) with molybdenum disulfide (MoS 2 ) monolayers have been intensively studied owing to their superior mechanical durability and stability. However, the limited output performance resulting from a small active area and low strain levels continues to pose a significant challenge that should be overcome. Herein, we report a novel strategy for the epoch-making output performance of a PENG with a MoS 2 monolayer by adopting the additive strain concentration concept. The simulation study indicates that strain in the MoS 2 monolayer can be initially augmented by the wavy structure resulting from the prestretched poly(dimethylsiloxane) (PDMS) and is further increased through flexural deformation (i.e., bending). Based on these studies, we have developed concentrated strain-applied PENGs with MoS 2 monolayers. The wavy structures effectively applied strain to the MoS 2 monolayer and generated a piezoelectric output voltage and current of around 580 mV and 47.5 nA, respectively. Our innovative approach to enhancing the performance of PENGs with MoS 2 monolayers through the artificial dual strain concept has led to groundbreaking results, achieving the highest recorded output voltage and current for PENGs based on two-dimensional (2D) materials, which provides unique opportunities for the 2D-based energy harvesting field and structural insight into how to improve the net strain on 2D materials.

One-dimensional (1D) magnetic material systems have attracted widespread interest from researchers because of their peculiar physical properties and potential applications in spintronics devices. However, the synthesis of 1D magnetic atomic chains has seldom been investigated. Here, we developed an iodine-assisted vacuum chemical vapor-phase transport (I-VCVT) method, utilizing single-walled carbon nanotubes (SWCNTs) with 1D cavities as templates, and high-quality and high-efficiency fabrication of 1D atomic chains of CrCl 3 was achieved. Furthermore, the structure of CrCl 3 atomic chains in the confined space of SWCNTs was analyzed in detail, and the charge transfer between the 1D atomic chains and SWCNTs was investigated through spectroscopic characterization. A comprehensive study of the dynamic magnetic properties revealed the existence of spin glass states and freezing of the 1D CrCl 3 atomic chains at around 3 K, which has never been seen in bulk CrCl 3 . Our work established an effective strategy for the control synthesis of 1D magnetic atomic chains with promising potential applications in further magnetic-based spintronics devices.

This paper reports the fabrication, testing and obtained performance of a plasmonic sensor employing a gold (Au) nanohole array chip coated with tungsten disulphide (WS 2 ), which is then functionalized for the detection of protein-protein interactions. A key novelty is that the WS 2 was deposited as a monoatomic layer using a wafer-scale synthesis method that successfully provided a film of both high quality and uniform thickness. The deposited WS 2 film was transferred onto a Au nanohole array chip using a novel method and was subsequently functionalized with biotin. The final sensor was tested and it demonstrated efficient real-time and label-free plasmonic detection of biotin-streptavidin coupling. Specifically, compared to a standard ( i.e. uncoated) Au nanohole-based sensor, our WS 2 -coated Au nanohole array boosted the spectral shift of the resonance wavelength by ∼190%, resulting in a 7.64-fold improvement of the limit of detection (LOD)., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that influenced the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Carbon nanotube (CNT)/copper (Cu) composite fibers are placed great expectations as the next generation of light-weight, conductive wires. However, the electrical and mechanical performances still need to be enhanced. Herein, we demonstrate a strategy that is electrodeposition Cu on thiolated CNT fibers to solve the grand challenge which is enhancing the performance of CNT/Cu composite fibers. Thiol groups are introduced to the surface of the CNT fibers through a controllable O 2 plasma carboxylation process and amide reaction. Compared with CNT/Cu composite fibers, there are 82.7% and 29.6% improvements in electrical conductivity and tensile strength of interface thiol-modification composite fibers. The enhancement mechanism is also explored that thiolated CNT fibers could make strong interactions between Cu and CNT, enhancing the electrical and mechanical performance of CNT/Cu composites. This work proposes a convenient, heat-treatment-free strategy for high-performance CNT/Cu composite fibers, which can be manufactured for large-scale production and applied to next-generation conductive wires., (© 2022 IOP Publishing Ltd.)

Recently, as an elementary material, tellurium (Te) has received widespread attention for its high carrier mobility, intriguing topological properties, and excellent environmental stability. However, it is difficult to obtain two-dimensional (2D) Te with high crystalline quality owing to its intrinsic helical chain structure. Herein, a facile strategy for controllable synthesis of high-quality 2D Te nanoflakes through chemical vapor transport in one step is reported. With carefully tuning the growth kinetics determined mainly by temperature, tellurium nanoflakes in lateral size of up to ∼40 μm with high crystallinity can be achieved. We also investigated the second harmonic generation of Te nanoflakes, which demonstrates that it can be used as frequency doubling crystals and has potential applications in nonlinear optical devices. In addition, field effect transistor devices based on the 2D Te nanoflakes were fabricated and exhibited excellent electrical properties with high mobility of 379 cm 2 V -1 s -1 ., Competing Interests: The authors declare no competing interests., (© 2021 The Authors.)

Reducing the lateral scale of two-dimensional (2D) materials to one-dimensional (1D) has attracted substantial research interest not only to achieve competitive electronic applications but also for the exploration of fundamental physical properties. Controllable synthesis of high-quality 1D nanoribbons (NRs) is thus highly desirable and essential for further study. Here, we report the implementation of supervised machine learning (ML) for the chemical vapor deposition (CVD) synthesis of high-quality quasi-1D few-layered WTe 2 NRs. Feature importance analysis indicates that H 2 gas flow rate has a profound influence on the formation of WTe 2 , and the source ratio governs the sample morphology. Notably, the growth mechanism of 1T' few-layered WTe 2 NRs is further proposed, which provides new insights for the growth of intriguing 2D and 1D tellurides and may inspire the growth strategies for other 1D nanostructures. Our findings suggest the effectiveness and capability of ML in guiding the synthesis of 1D nanostructures, opening up new opportunities for intelligent materials development.

Electrolyte-accessibly porous yet densely packed MXene composite electrodes with high ion-accessible surface and rapid ion transport rate have shown exceptional promise for high-volumetric-performance supercapacitors (SCs), but they are largely limited by the insufficient rate capability and poor electrochemical cyclability, in association with the instability in mechanical robustness of the porous network structures. Taking advantage of chemical bonding design, herein a black phosphorus (BP)@MXene compact film of 3D porous network structure is successfully made by in situ growth of BP nanoparticles on crumbled MXene flakes. The strong interfacial interaction (Ti-O-P bonds) formed at the BP-MXene interfaces not only enhances the atomic charge polarization in the BP-MXene heterostructures, leading to efficient interfacial electron transport, but also stabilizes the 3D porous yet dense architecture with much improved mechanical robustness. Consequently, fully packaged SCs using the BP@MXene composite films with a practical-level of mass loading (∼15 mg cm -2 ) deliver a high stack volumetric energy density of 72.6 Wh L -1 , approaching those of lead-acid batteries (50-90 Wh L -1 ), together with a long-term stability (90.58% capacitance retention after 50000 cycles). The achievement of such high energy density bridges the gap between traditional batteries and SCs and represents a timely breakthrough in designing compact electrodes toward commercial-level capacitive energy storage.

FeTe 1- x Se x , a promising layered material used to realize Majorana zero modes, has attracted enormous attention in recent years. Pulsed laser deposition (PLD) and molecular-beam epitaxy (MBE) are the routine growth methods used to prepare FeTe 1- x Se x thin films. However, both methods require high-vacuum conditions and polished crystalline substrates, which hinder the exploration of the topological superconductivity and related nanodevices of this material. Here we demonstrate the growth of the ultrathin FeTe 1- x Se x superconductor by a facile, atmospheric pressure chemical vapor deposition (CVD) method. The composition and thickness of the two-dimensional (2D) FeTe 1- x Se x nanosheets are well controlled by tuning the experimental conditions. The as-prepared FeTe 0.8 Se 0.2 nanosheet exhibits an onset superconducting transition temperature of 12.4 K, proving its high quality. Our work offers an effective strategy for preparing the ultrathin FeTe 1- x Se x superconductor, which could become a promising platform for further study of the unconventional superconductivity in the FeTe 1- x Se x system.

Cocatalyst design is a key approach to acquire high solar-energy conversion efficiency for photocatalytic hydrogen evolution. Here a new in situ vapor-phase (ISVP) growth method is developed to construct the cocatalyst of 2D PtS nanorectangles (a length of ∼7 nm, a width of ∼5 nm) on the surface of g-C 3 N 4 nanosheets. The 2D PtS nanorectangles/g-C 3 N 4 nanosheets (PtS/CN) show an unusual metal sulfide-support interaction (MSSI), which is evidenced by atomic resolution HAADF-STEM, synchrotron-based GIXRD, XPS and DFT calculations. The effect of MSSI contributes to the optimization of geometrical structure and energy-band structure, acceleration of charge transfer, and reduction of hydrogen adsorption free energy of PtS/CN, thus yielding excellent stability and an ultrahigh photocatalytic H 2 evolution rate of 1072.6 μmol h -1 (an apparent quantum efficiency of 45.7% at 420 nm), up to 13.3 and 1532.3 times by contrast with that of Pt nanoparticles/g-C 3 N 4 nanosheets and g-C 3 N 4 nanosheets, respectively. This work will provide a new platform for designing high-efficiency photocatalysts for sunlight-driven hydrogen generation.

The relatively high recombination rate of charges remains the most critical limiting factor for solar-driven water splitting for hydrogen generation. Herein, a tandem 0D/2D/2D NbS 2 quantum dot/Nb 2 O 5 nanosheet/g-C 3 N 4 flake (NSNOCN) system is designed. Owing to the unique spatial-arrangement and elaborate morphology of 0D NbS 2 , 2D Nb 2 O 5 , and 2D g-C 3 N 4 in the newly designed NSNOCN, plenty of spatial charge-transfer cascades from g-C 3 N 4 to NbS 2 via Nb 2 O 5 are formed to accelerate separation and transfer of charges significantly, thus contributing to a high photocatalytic H 2 generation rate of 13.99 mmol h -1 g -1 (an apparent quantum efficiency of 10.8% at 420 nm), up to 107.6 and 43.7 times by contrast with that of g-C 3 N 4 and Nb 2 O 5 , respectively. This work can provide a new platform in the design of artificial photocatalytic systems with high charge-transfer efficiency., (© 2020 Wiley-VCH GmbH.)

Two-dimensional (2D) magnets with intrinsic ferromagnetic/antiferromagnetic (FM/AFM) ordering are highly desirable for future spintronic devices. However, the direct growth of their crystals is in its infancy. Here we report a chemical vapor deposition approach to controllably grow layered tetragonal and non-layered hexagonal FeTe nanoplates with their thicknesses down to 3.6 and 2.8 nm, respectively. Moreover, transport measurements reveal these obtained FeTe nanoflakes show a thickness-dependent magnetic transition. Antiferromagnetic tetragonal FeTe with the Néel temperature (T N ) gradually decreases from 70 to 45 K as the thickness declines from 32 to 5 nm. And ferromagnetic hexagonal FeTe is accompanied by a drop of the Curie temperature (T C ) from 220 K (30 nm) to 170 K (4 nm). Theoretical calculations indicate that the ferromagnetic order in hexagonal FeTe is originated from its concomitant lattice distortion and Stoner instability. This study highlights its potential applications in future spintronic devices.

Two-dimensional (2D) materials 1-5 offer a unique platform from which to explore the physics of topology and many-body phenomena. New properties can be generated by filling the van der Waals gap of 2D materials with intercalants 6,7 ; however, post-growth intercalation has usually been limited to alkali metals 8-10 . Here we show that the self-intercalation of native atoms 11,12 into bilayer transition metal dichalcogenides during growth generates a class of ultrathin, covalently bonded materials, which we name ic-2D. The stoichiometry of these materials is defined by periodic occupancy patterns of the octahedral vacancy sites in the van der Waals gap, and their properties can be tuned by varying the coverage and the spatial arrangement of the filled sites 7,13 . By performing growth under high metal chemical potential 14,15 we can access a range of tantalum-intercalated TaS(Se) y , including 25% Ta-intercalated Ta 9 S 16 , 33.3% Ta-intercalated Ta 7 S 12 , 50% Ta-intercalated Ta 10 S 16 , 66.7% Ta-intercalated Ta 8 Se 12 (which forms a Kagome lattice) and 100% Ta-intercalated Ta 9 Se 12 . Ferromagnetic order was detected in some of these intercalated phases. We also demonstrate that self-intercalated V 11 S 16 , In 11 Se 16 and Fe x Te y can be grown under metal-rich conditions. Our work establishes self-intercalation as an approach through which to grow a new class of 2D materials with stoichiometry- or composition-dependent properties.

The semiconductor industry is increasingly of the view that Moore's law-which predicts the biennial doubling of the number of transistors per microprocessor chip-is nearing its end. Consequently, the pursuit of alternative semiconducting materials for nanoelectronic devices, including single-walled carbon nanotubes (SWNTs), continues. Arrays of horizontal nanotubes are particularly appealing for technological applications because they optimize current output. However, the direct growth of horizontal SWNT arrays with controlled chirality, that would enable the arrays to be adapted for a wider range of applications and ensure the uniformity of the fabricated devices, has not yet been achieved. Here we show that horizontal SWNT arrays with predicted chirality can be grown from the surfaces of solid carbide catalysts by controlling the symmetries of the active catalyst surface. We obtained horizontally aligned metallic SWNT arrays with an average density of more than 20 tubes per micrometre in which 90 per cent of the tubes had chiral indices of (12, 6), and semiconducting SWNT arrays with an average density of more than 10 tubes per micrometre in which 80 per cent of the nanotubes had chiral indices of (8, 4). The nanotubes were grown using uniform size Mo 2 C and WC solid catalysts. Thermodynamically, the SWNT was selectively nucleated by matching its structural symmetry and diameter with those of the catalyst. We grew nanotubes with chiral indices of (2m, m) (where m is a positive integer), the yield of which could be increased by raising the concentration of carbon to maximize the kinetic growth rate in the chemical vapour deposition process. Compared to previously reported methods, such as cloning, seeding and specific-structure-matching growth, our strategy of controlling the thermodynamics and kinetics offers more degrees of freedom, enabling the chirality of as-grown SWNTs in an array to be tuned, and can also be used to predict the growth conditions required to achieve the desired chiralities.

Objective: To evaluate the clinical results and the value of the posterior approach 360° vertebral canal decompression and transfacet discectomy combined with interbody fusion and pedicle screw internal fixation for the treatment of ossifying thoracic disc herniation., Methods: Thirty nine cases of ossifying thoracic disc herniation who accepted the posterior approach 360° vertebral canal decompression and transfacet discectomy combined with interbody fusion and pedicle screw internal fixation were included in this study. There were 21 male and 18 female patients. The age ranged from 33 to 69 years, with an average of 53 years. The course of disease ranged from 1 month to 18 months, with an average of 6.5 months. The lesion locations were T7-8 for 1 case, T8-9 for 4 cases, T9-10 for 9 cases, T10-11 for 7 cases, T11-12 for 10 cases, T12-L1 for 6 cases, and both T11-12 and T12-L1 for 2 cases. The clinical results were evaluated by Otani scored system., Results: The operative time was from 2.5 to 5.0 hours, with average of 3.3 hours. The blood loss was from 400 to 2 000 ml, with average of 850 ml. All patients were successfully operated without neurological symptoms aggravation and accidents. The followed-up period was 24 to 60 months, mean 40.5 months. According to Otani scored system, there were excellent results in 16 cases and good results in 18 cases. The clinical satisfaction rate was 87.2%. All obtained bony fusion without instrument failure., Conclusion: Posterior approach 360° vertebral canal decompression and transfacet discectomy combined with interbody fusion and pedicle screw internal fixation is a safe and effective surgical procedure for the treatment of ossifying thoracic disc herniation.