Yourong Tao

Fabrication and photoluminescence characteristics of single crystalline In2O3 nanowires

Abstract Single crystalline In2O3 nanowires (InONWs) have been synthesized by carbothermal reduction reaction between indium oxide and active carbons at 980 °C in flowing nitrogen atmosphere. Transmission electron microscopy (TEM) image shows the formation of the nanowires at a diameter of about 20–200 nm and a length of up to hundreds of micrometers. The nanowires can emit stable and high brightness blue light at 416 and 435 nm under excitation at 260 nm. The growth process of the nanowires may be explained by vapor–solid mechanism.

Flexible photodetector from ultraviolet to near infrared based on a SnS2 nanosheet microsphere film

A new flexible ultraviolet (UV) to near infrared (NIR) photodetector based on a SnS2 nanosheet self-assembled microsphere film has been fabricated onto a transparent polypropylene (PP) film using double-side adhesive tape, and its light-induced electric properties were investigated in detail. The detector demonstrates a remarkable photoresponse from 300 to 830 nm, a remarkable photocurrent depending on the optical power and light wavelength, as well as an excellent photoswitch effect and stability. In addition, another new rigid photodetector based on the same SnS2 microsphere film has been fabricated on a SiO2/Si substrate, showing similar photosensitive properties. It suggests that SnS2 nanosheet microspheres are potential candidates for high-performance nanoscale optoelectronic devices, and the SnS2-microsphere-based photodetector can be applied as a photodetector in the range of UV to NIR light because of its low cost and nontoxicity.

Synthesis and characterization of self-assembling (NH4)0.5V2O5 nanowires

Large-scale long (NH4)0.5V2O5 nanowires have been synthesized by rational hydrothermal treatment of ammonium metavanadate at 170 °C. Scanning electron microscope and transmission electron microscope analyses show that the nanowires have diameters of about 20–80 nm, and lengths up to 0.5 mm. Some self-assembled nanobelts are observed with a thickness of 18 nm and width of 100–200 nm. Electrical transport measurements shows that the nanowires are semiconductors with a conductivity of about 10−3 S cm−1 at room temperature. The conduction mechanism can be explained by small polaron hopping in transition metal oxides.

Flexible Visible-Light Photodetectors with Broad Photoresponse Based on ZrS3 Nanobelt Films

Two new flexible visible-light photodetectors based on ZrS3 nanobelts films are fabricated on a polypropylene (PP) film and printing paper, respectively, by an adhesive-tape transfer method, and their light-induced electric properties are investigated in detail. The devices demonstrate a remarkable response to 405 to 780 nm light, a photocurrent that depends on the optical power and light wavelength, and an excellent photoswitching effect and stability. This implies that ZrS3 nanobelts are prospective candidates for high-performance nanoscale optoelectronic devices that may be practically applied in photodetection of visible to near infrared light. The facile fabrication method is extendable to flexible nanodevices with different nanostructures.

Enhanced catalytic activity of α-Fe2O3 nanorods enclosed with {110} and {001} planes for methane combustion and CO oxidation

Hematite (α-Fe2O3) nanorods, nanotubes, and nanocubes were selectively synthesized via a hydrothermal process and subsequent calcination treatment. The nanorods showed higher catalytic activity than the nanotubes and the nanocubes for methane combustion and CO oxidation. It may be attributed to the highest occupancy of iron ions on the surface of the nanorods.

Controllable growth of NbTe4 micro/nanostructures on Nb substrates and their field-emission performance

Single-crystalline NbTe4 microcone, microplate, and nanorod arrays were grown on Nb substrates by a surface-assisted chemical-vapor-transport under different conditions. The microcones are composed of small and large cones with a bending top. The small cones have a top diameter of about 0.2 µm, a bottom diameter of about 1.2 µm, and a length up to approx. 7.7 µm. The large cones originate from self-assembled small cones. The microplates mostly stand on Nb foils, with a diameter of about 2–3 µm and a thickness from 50 to 250 nm. The nanorods have a rectangle section of 250 × 150 to 250 × 250 nm2 or a triangle section with a side of about 250 nm, and a length up to 4.5 µm, partly standing on the substrates. Their growth mechanisms are briefly discussed. Field-emission experiments showed that the three micro/nanostructures have a notable emission current, and their turn-on fields (defined as the electric field required to produce a current density of 10 µA cm−2) are 4.7, 2.0, and 1.9 V µm−1, respectively, suggesting their potential application in electron emission devices.