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This article studies the role of electrochemical parameters in controlling the morphology of oxidized TiO2 nanotubes and the electrochemical performance of modified TiO2 nanotubes. Humidity is a key factor for fabricating TiO2 nanotubes. When the relative humidity belows 70%, the TiO2 nanotubes can be successfully prepared. What's more, by changing the anodization voltage and time, the diameter and the length of TiO2 nanotubes can be adjusted. In addition, the TiO2 nanotubes are modified through electrochemical self-doping and loading Pt metal particles on the surface of the nanotubes, which promotes the performance of the supercapacitor. The sample anodized at 100 V for 3 h has a specific capacity of up to 2.576 mF/cm² at a scan rate of 100 mV/s after self-doping, and its capacity retention rate still remains at 89.55% after 5 000 cycles, demonstrating excellent cycling stability. The Pt-modified sample has a specific capacity of up to 3.486 mF/cm² at the same scan rate, exhibiting more outstanding electrochemical performance. [ABSTRACT FROM AUTHOR]

As a multifunctional material, TiO2 shows excellent performance in catalytic degradation and lithium-ion storage. However, high electron-hole pair recombination, poor conductivity, and low theoretical capacity severely limit the practical application of TiO2. Herein, TiO2 nanotube (TiO2 NT) with a novel double-layer honeycomb structure were prepared by two-step electrochemical anodization. Honeycombed TiO2 NT arrays possess clean top surfaces and a long-range ordering, which greatly facilitates the preparation of high-performance binary and ternary materials. A binary TiO2 nanotube@Au nanoparticle (TiO2 NT@Au NP) composite accompanied by appropriately concentrated and uniformly distributed gold particles was prepared in this work. Interestingly, the TiO2 nanotube@Au nanoparticle (TiO2 NT@Au NP) composites not only showed the excellent catalytic degradation effect of methylene blue, but also demonstrated large lithium-ion storage capacity (310.6 μAh cm−2, 1.6 times of pristine TiO2 NT). Based on the realization of the controllable fabrication of binary TiO2 nanotube@MoS2 nanosheet (TiO2 NT@MoS2 NS) composite, ternary TiO2 nanotube@MoS2 nanosheet@Au nanoparticle (TiO2 NT@MoS2 NS@Au NP) composite with abundant defects and highly ordered structure was also innovatively designed and fabricated. As expected, the TiO2 NT@MoS2 NS@Au NP anode exhibits extremely high initial discharge specific capacity (487.4 μAh cm−2, 2.6 times of pristine TiO2 NT) and excellent capacity retention (81.0%). [ABSTRACT FROM AUTHOR]

Abstract Novel hierarchical Cd4SiS6/SiO2 based heterostructure nanowire arrays were fabricated on silicon substrates by a one-step thermal evaporation of CdS powder. The as-grown products were characterized using scanning electron microscopy, X-ray diffraction, and transmission electron microscopy. Studies reveal that a typical hierarchical Cd4SiS6/SiO2 heterostructure nanowire is composed of a single crystalline Cd4SiS6 nanowire core sheathed with amorphous SiO2 sheath. Furthermore, secondary nanostructures of SiO2 nanowires are highly dense grown on the primary Cd4SiS6 core-SiO2 sheath nanowires and formed hierarchical Cd4SiS6/SiO2 based heterostructure nanowire arrays which stand vertically on silicon substrates. The possible growth mechanism of hierarchical Cd4SiS6/SiO2 heterostructure nanowire arrays is proposed. The optical properties of hierarchical Cd4SiS6/SiO2 heterostructure nanowire arrays are investigated using Raman and Photoluminescence spectroscopy.

In this study, α-MnO2 and Fe2O3 nanomaterials are prepared on a carbon fiber modified with carbon nanotubes to produce the nonbinder core–shell positive (α-MnO2@CNTs/CC) and negative (Fe2O3@CNTs/CC) electrodes that can be operated in a wide voltage window in ultrafast asymmetrical flexible supercapacitors. MnO2 and Fe2O3 have attracted wide research interests as electrode materials in energy storage applications because of the abundant natural resources, high theoretical specific capacities, environmental friendliness, and low cost. The electrochemical performance of each electrode is assessed in 1 M Na2SO4 and the energy storage properties of the supercapacitors consisting of the two composite electrodes are determined in Na2SO4 and EMImBF4 electrolytes in the 2 V and 4 V windows. The 2 V supercapacitor can withstand a large scanning rate of 5000 mV S−1 without obvious changes in the cyclic voltammetry (CV) curves, besides showing a maximum energy density of 57.29 Wh kg−1 at a power density of 833.35 W kg−1. Furthermore, the supercapacitor retains 87.06% of the capacity after 20,000 galvanostatic charging and discharging (GCD) cycles. The 4 V flexible supercapacitor shows a discharging time of 1260 s and specific capacitance of 124.8 F g−1 at a current of 0.5 mA and retains 87.77% of the initial specific capacitance after 5000 GCD cycles. The mechanical robustness and practicality are demonstrated by physical bending and the powering of LED arrays. In addition, the contributions of the active materials to the capacitive properties and the underlying mechanisms are explored and discussed [ABSTRACT FROM AUTHOR]

Investigations of two-dimensional ( 2D ) / one-dimensional ( 1D) van der Waals ( vdW) heterojunctions have attracted significant attention due to their excellent properties such as the smooth heterointerface, the highly gate-tunable bandgap, and the ultrafast carrier transport. However, the complicated method of manufacturing vdW heterojunction represents a major problem that severely limits their practical applications. Herein, we develop onestep hydrothermal method and use it to synthesize 2D PbI2 / 1D Pb5S2I6 vdW heterojunction. The PbI2 / Pb5S2I6 vdW heterojunction photodetector(PD) displays lower dark current (<20 pA), higher responsivity (up to 134 mA·W-1), self-powered and wider response spectrum in comparison with that of pristine PbI2 PD and Pb5S2I6 PD. This one-step hydrothermal method provides a new idea for preparing other mixed-dimensional heterojunction. [ABSTRACT FROM AUTHOR]

The neuroendocrine carcinomas (NECs) of the head and neck are rare. The purpose of this article is to explore the diagnosis and treatment of NECs in the ear and larynx. We report a case of a patient with NECs found in the ear and throat simultaneously, and the relevant literatures are reviewed. It is difficult to identify which is the original site. There is no specific clinical manifestation of NECs in the ear and throat, and carcinoid syndrome is a rare situation. Surgery is still the preferred treatment for this disease. For patients with metastasis, radiotherapy and/or chemotherapy are required. [ABSTRACT FROM AUTHOR]

A flexible anode composite, carbon cloth @ SiO2 composite(CC @ SiO2), was synthesized by a one-step solution method using tetraethyl orthosilicate(TEOS) as the silica source. CC @ SiO2 can be directly used as the negative electrode material for lithium-ion battery, and its initial reversible deintercalation capacity reaches 1 358. 7 mA·h·g-1. The electrode shows a capacity of 863. 8 mA·h·g-1 up to 130 cycles at 0. 5 A·g-1, displaying excellent rate performance and cycle stability. [ABSTRACT FROM AUTHOR]

AB2O4-type binary-transition metal oxides (BTMOs) of CuCo2O4 and MnCo2O4 were successfully prepared on ordered macroporous electrode plates (OMEP) for supercapacitors. Under the current density of 5 mA cm−2, the CuCo2O4/OMEP electrode achieved a specific capacitance of 1199 F g−1. The asymmetric supercapacitor device prepared using CuCo2O4/OMEP as the positive electrode and carbon-based materials as the negative electrode (CuCo2O4/OMEP//AC) achieved the power density of 14.58 kW kg−1 under the energy density of 11.7 Wh kg−1. After 10,000 GCD cycles, the loss capacitance of CuCo2O4/OMEP//AC is only 7.5% (the retention is 92.5%). The MnCo2O4/OMEP electrode shows the specific and area capacitance of 843 F g−1 and 5.39 F cm−2 at 5 mA cm−2. The MnCo2O4/OMEP-based supercapacitor device (MnCo2O4/OMEP//AC) has a power density of 8.33 kW kg−1 under the energy density of 11.6 Wh kg−1 and the cycle stability was 90.2% after 10,000 cycles. The excellent power density and cycle stability prove that the prepared hybrid supercapacitor fabricated under silicon process has a good prospect as the power buffer device for solar cells. [ABSTRACT FROM AUTHOR]

Highlights: [•] Because the ITO/AZO double films lead to a great decrease of the lateral resistance. [•] The photon current can easily flow through top film entering the Cu front contact. [•] High photocurrent is obtained under a reverse bias. [ABSTRACT FROM AUTHOR]