24 research outputs found
Development and characterisation of multifunctional one-dimensional fibres reinforced composite coatings
Nanocomposite coatings are attractive due to their unique mechanical, physical and multifunctional properties, which can address the limitations of conventional monolithic structures to achieve an excellent combination of strength, stiffness, toughness, and some other functional properties. In this study, a novel in-situ low temperature (below 500ºC) hybrid plasma technology combining active-screen plasma co-sputtering and PECVD has been developed to cost-effectively generate vertically aligned carbon nanotubes (VACNTs) films. A two-step approach has been employed to develop VACNTs reinforced composite coatings. A well-designed CNTs reinforced diamond-like carbon (DLC) composite coating can be formed using the PECVD. Besides, the Ag wires reinforced composite coatings have been deposited through a one-step approach using the advanced hybrid plasma technology combining ASP co-sputtering and plasma carburising in a plasma ambient of CH4 (1.5%) and H2 (98.5%). SEM, TEM, XRD, XPS have been applied to characterise the morphologies and microstructures of these novel composite coatings
A novel hybrid method combining ASP with PECVD for in-situ low temperature synthesis of vertically aligned carbon nanotube films
In situ synthesis of the one-dimensional Ag wires reinforced composites film by a novel active screen plasma process:nanostructure and excellent adhesion resistance
Synthesis and in-vitro antibacterial properties of a functionally graded Ag impregnated composite surface
Morpho butterfly-inspired optical diffraction, diffusion, and bio-chemical sensing
Morpho-butterfly is well-known for the blue colouration in its tiny wing scales and finds applications in colour filters, anti-reflecting coatings and optical devices. Herein, the structural optical properties of the Morpho peleides-butterfly wing scales were examined through light reflection, diffraction and optical diffusion. The light diffraction property from wing scales was investigated through experiments and computation modelling. Broadband reflection variation was observed from different parts of the dorsal wings at broadband light illumination due to tiny structural variations, as verified by electronic microscopic images. The periodic nanostructures showed well-defined first-order diffraction through monochromatic (red, green and blue) and broadband light at normal illumination. Polyvinyl alcohol (PVA) embedded with Morpho peleides-butterfly wing scales acts as an optical diffuser to produce soft light. Light diffraction and diffusion properties were measured by angle-resolve experiments, followed by computational modelling. The maximum optical diffusion property at ∼185° from the wing scales was observed using broadband light at normal illumination. Finally, Morpho peleides-butterfly based submicron nanostructures were utilized to demonstrate bio-inspired chemical sensing
Thin film electrodes from Pt nanorods supported on aligned N-CNTs for proton exchange membrane fuel cells
The enhanced performance of carbon nanotubes (CNTs) over carbon black as a catalyst support and the outstanding catalytic activities of one-dimensional (1D) Pt nanostructures endow them big potential for applications in fuel cells. However, the research has been mainly focused on the materials, and a combination of both 1D Pt nanostructures and CNTs to fabricate practical high power performance fuel cell electrodes still remains a challenge. In this work, we demonstrate catalyst electrodes from Pt nanorods grown on aligned nitrogen doped CNTs for proton exchange membrane fuel cell (PEMFC) applications. Short Pt nanorods are grown on CNTs deposited directly on 16 cm2 carbon paper gas diffusion layers (GDLs) via plasma enhanced chemical vapour deposition (PECVD) and nitrided using active screen plasma (ASP) treatment, which are directly employed as cathodes for H2/air PEMFCs. The thin open catalyst layer effectively enhances mass transfer performance and, with a less than half of the Pt loading, 1.23 fold power density is achieved as compared with that from commercial Pt/C catalysts. A better durability is also confirmed which can be attributed to the good structure stability of nanorods and the enhancement effects from the N-CNT support
Insights into the Enhanced Catalytic Activity of Fe-Doped LiCoPO 4 for the Oxygen Evolution Reaction
Developing highly active and stable catalysts for the oxygen evolution reaction (OER) is of significant importance for numerous electrochemical energy conversion devices. Previous accomplishments have shown that LiCoPO4 is a promising catalyst for OER activity; however, its activity and stability at high potential still need improvement to meet the requirements of practical applications, and further studies are needed for its catalytic mechanism. Here, we report a series of Fe-doped LiCoPO4 materials that exhibit excellent OER catalytic behaviors at high potential and elucidate their catalytic mechanism. Fe-doping enhances the OER activity through synergistic coupling effects, which is strongly influenced by the divalent Co2+ and Fe2+ cations rather than the trivalent Co3+ and Fe3+ cations. The possible rate-determining step is proposed to be the formation of *OOH derived from *O based on the H/D kinetic isotopic effect experiment
Cholesterol esterification inhibition and gemcitabine synergistically suppress pancreatic ductal adenocarcinoma proliferation.
Recent advances have recognized metabolic reprogramming as an underlying mechanism for cancer drug resistance. However, the role of cholesterol metabolism in drug resistance remain elusive. Herein, we report an increased accumulation of cholesteryl ester in gemcitabine-resistant pancreatic ductal adenocarcinoma (PDAC) cells. A potent inhibitor of acyl-CoA cholesterol acyltransferase-1 (ACAT-1), avasimibe, effectively suppressed proliferation of gemcitabine-resistant PDAC cells. Combination of avasimibe and gemcitabine showed strong synergistic effect in suppressing PDAC cell viability in vitro and tumor growth in vivo. Immunoblotting analysis suggests downregulation of Akt by avasimibe is likely to contribute to the synergism. Collectively, our study demonstrates a new combinational therapeutic strategy to overcome gemcitabine resistance for PDAC treatment
Morpho butterfly-inspired optical diffraction, diffusion, and bio-chemical sensing
Morpho-butterfly is well-known for the blue colouration in its tiny wing scales and finds applications in colour filters, anti-reflecting coatings and optical devices. Herein, the structural optical properties of the Morpho peleides-butterfly wing scales were examined through light reflection, diffraction and optical diffusion. The light diffraction property from wing scales was investigated through experiments and computation modelling. Broadband reflection variation was observed from different parts of the dorsal wings at broadband light illumination due to tiny structural variations, as verified by electronic microscopic images. The periodic nanostructures showed well-defined first-order diffraction through monochromatic (red, green and blue) and broadband light at normal illumination. Polyvinyl alcohol (PVA) embedded with Morpho peleides-butterfly wing scales acts as an optical diffuser to produce soft light. Light diffraction and diffusion properties were measured by angle-resolve experiments, followed by computational modelling. The maximum optical diffusion property at ∼185° from the wing scales was observed using broadband light at normal illumination. Finally, Morpho peleides-butterfly based submicron nanostructures were utilized to demonstrate bio-inspired chemical sensing.H. B. thanks the Welcome Trust for research funding