Carbon nanotube hybrids with MoS2 and WS2 synthesized with control of crystal structure and morphology

In this work, a very sensitive electrochemical sensor for the determination of pentachlorophenol (PCP) was constructed based on the electrocatalytic activity of the composite of ZnSe quantum dots (ZnSe QDs) decorated multiwall carbon nanotubes (MWCNTs) (ZnSe QDs-MWCNTs). The behaviors of PCP on the surface of ZnSe QDs-MWCNT modified electrode showed that the composite of ZnSe QDs-MWCNTs introduced a favorable access for the electron transfer and make an obvious electrocatalytic activity toward the oxidation of PCP. Differential pulse voltammetry (DPV) was used for the quantitative determination of PCP. Under the optimum conditions, the peak current of PCP was proportional to its concentration at the range of 8.0 × 10−8 to 4.0 × 10−6 mol L−1 with a detection limit 2.0 × 10−9 mol L−1 (S/N = 3). Compared with the reported papers, the proposed method was more sensitive and simple. The developed method was successfully applied for the determination of PCP in fish meat with satisfactory recoveries.

Sensitive electrochemical sensor for the determination of pentachlorophenol in fish meat based on ZnSe quantum dots decorated multiwall carbon nanotubes nanocomposite

We report a simple approach to fabricate hybrid solar cells (HSCs) based on a single-walled carbon nanotube (SWCNT) film and thin film hydrogenated amorphous silicon (a-Si:H). Randomly oriented high-quality SWCNTs with conductivity enhanced by means of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate are used as a window layer and a front electrode. A series of HSCs are fabricated in ambient conditions with varying SWCNT film thicknesses. The polymethylmethacrylate layer drop-casted on fabricated HSCs reduces the reflection fourfold and enhances the short-circuit J sc , open-circuit V oc , and efficiency by nearly 10%. A state-of-the-art J-V performance is shown for SWCNT/a-Si HSC with an open-circuit voltage of 900 mV and an efficiency of 3.4% under simulated one-sun AM 1.5 G direct illumination.

http://iopscience.iop.org/article/10.1088/1361-6528/aaa647/pdf

Enhanced efficiency of hybrid amorphous silicon solar cells based on single-walled carbon nanotubes and polymer composite thin film

Field electron emission (FEE) properties of vertically aligned hexagonal boron nitride nanowalls (hBNNWs) grown on Si have been markedly enhanced through the use of nitrogen doped nanocrystalline diamond (nNCD) films as an interlayer. The FEE properties of hBNNWs-nNCD heterostructures show a low turn-on field of 15.2 V/μm, a high FEE current density of 1.48 mA/cm2 and life-time up to a period of 248 min. These values are far superior to those for hBNNWs grown on Si substrates without the nNCD interlayer, which have a turn-on field of 46.6 V/μm with 0.21 mA/cm2 FEE current density and life-time of 27 min. Cross-sectional TEM investigation reveals that the utilization of the diamond interlayer circumvented the formation of amorphous boron nitride prior to the growth of hexagonal boron nitride. Moreover, incorporation of carbon in hBNNWs improves the conductivity of hBNNWs. Such a unique combination of materials results in efficient electron transport crossing nNCD-to-hBNNWs interface and inside the hBNNWs that results in enhanced field emission of electrons. The prospective application of these materials is manifested by plasma illumination measurements with lower threshold voltage (370 V) and longer life-time, authorizing the role of hBNNWs-nNCD heterostructures in the enhancement of electron emission.

/pdf/enhanced-optoelectronic-performances-of-vertically-aligned-4kbaizlx0e.pdf

Enhanced optoelectronic performances of vertically aligned hexagonal boron nitride nanowalls-nanocrystalline diamond heterostructures

In the age of hand-held portable electronics, the need for robust, stable and long-life cathode materials has become increasingly important. Herein, a novel heterogranular-structured diamond-gold nanohybrids (HDG) as a long-term stable cathode material for field-emission (FE) display and plasma display devices is experimentally demonstrated. These hybrid materials are electrically conductive that perform as an excellent field emitters, viz. low turn-on field of 2.62 V/μm with high FE current density of 4.57 mA/cm(2) (corresponding to a applied field of 6.43 V/μm) and prominently high lifetime stability lasting for 1092 min revealing their superiority on comparison with the other commonly used field emitters such as carbon nanotubes, graphene, and zinc oxide nanorods. The process of fabrication of these HDG materials is direct and easy thereby paving way for the advancement in next generation cathode materials for high-brightness FE and plasma-based display devices.

Heterogranular-Structured Diamond-Gold Nanohybrids: A New Long-Life Electronic Display Cathode.

In this work, we described a facile route for the fabrication of free-standing single-walled carbon nanotubes (SWCNT)–CdSe quantum dots (QDs) hybrid ultrathin films and investigated their optoelectronic conversion properties. A free-standing SWCNT film with thickness of ∼36 nm was firstly prepared via vacuum filtration. The film was then immersed into the pre-synthesized oleic acid-capped CdSe QDs (average diameter of 3.5 nm) solution, where CdSe QDs anchored spontaneously onto the surface of SWCNT film to produce SWCNT–CdSe QDs hybrid film. By using pure SWCNT films in different thicknesses as bottom and top electrodes, a flexible all-carbon electrode optoelectronic conversion device with sandwich structure of SWCNT film (thickness of ∼200 nm)/SWCNT–CdSe QDs hybrid film (thickness of ∼36 nm)/SWCNT film (thickness of ∼36 nm) was constructed to generate optoelectronic conversion under illumination of solar-simulated light. Our results demonstrated that the all-carbon electrode structure was effective for charge separation and a sensitive and stable photocurrent signal could be produced in such a device. In addition, our SWCNT–CdSe QDs hybrid film exhibited high flexibility and durability. No clear change in the resistance of the film was detected under bending in various bending angles.

Wenhui Lv

Papers

Free-standing single-walled carbon nanotube–CdSe quantum dots hybrid ultrathin films for flexible optoelectronic conversion devices

Ratiometric SERS aptasensing for simultaneous quantitative detection of histamine and tyramine in fishes.