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A plasma gas bubble-in-liquid method for high production of selectable reactive species using a nanosecond pulse generator has been developed. The gas of choice is fed through a hollow needle in a point-to-plate bubble discharge, enabling improved selection of reactive species. The increased interface reactions, between the gas-plasma and water through bubbles, give higher productivity. H2O2 was the predominant species produced using Ar plasma, while predominantly [ABSTRACT FROM AUTHOR]

Biosensors based on microcantilevers convert biological recognition events into measurable mechanical displacements. They offer advantages such as small size, low sample volume, label-free detection, ease of integration, high-throughput analysis, and low development cost. The design and development of a microcantilever-based aptasensor employing SU-8 polymer as the fabrication material is presented in this paper. Aptamers are employed as bioreceptor elements because they exhibit superior specificity compared to antibodies due to their small size and physicochemical stability. To immobilise thrombin DNA aptamer on the bare SU-8 surface of the aptasensor, a combined plasma mode treatment method is implemented which modifies the surface of the aptasensor. Label-free detection of thrombin molecules using the fabricated aptasensor is successfully demonstrated. The measured deflection is one order of magnitude higher than that of a silicon nitride microcantilever biosensor. The developed aptasensor also demonstrates high specificity. [ABSTRACT FROM PUBLISHER]

We report the preparation of a novel nanocomposite architecture of α-LiFeO2–MWCNT based on clusters of α-LiFeO2 nanoparticles incorporated into multiwalled carbon nanotubes (MWCNTs). The composite represents a promising cathode material for lithium-ion batteries. The preparation of the nanocomposite is achieved by combining a molten salt precipitation process and a radio frequency oxygen plasma for the first time. We demonstrate that clusters of α-LiFeO2 nanoparticles incorporated into MWCNTs are capable of delivering a stable and high reversible capacity of 147 mA h g−1 at 1 C after 100 cycles with the first cycle Coulombic efficiency of ∼95%. The rate capability of the composite is significantly improved and its reversible capacity is measured to be 101 mA h g−1 at a high current rate of 10 C. Both rate capability and cycling stability are not simply a result of introduction of functionalized MWCNTs but most likely originate from the unique composite structure of clusters of α-LiFeO2 nanoparticles integrated into a network of MWCNTs. The excellent electrochemical performance of this new nanocomposite opens up new opportunities in the development of high-performance electrode materials for energy storage application using the radio frequency oxygen plasma technique. [ABSTRACT FROM AUTHOR]

Improvement of the binding of polypyrrole with PVDF (polyvinylidene fluoride) thin film using low pressure plasma was studied. The effects of various plasma gases i.e., Ar, O2 and Ar + O2 gases on surface roughness, surface chemistry and hydrophilicity were noted. The topographical change of the PVDF film was observed by means of scanning electron microscopy and chemical changes by X-ray photoelectron spectroscopy, with adhesion of polypyrrole (PPy) by abrasion tests and sheet resistance measurements. Results showed that the increase in roughness and surface functionalization by oxygen functional groups contributed to improved adhesion and Ar + O2 plasma gave better adhesion. [ABSTRACT FROM AUTHOR]

Liquid plasma, produced by nanosecond pulses, provides an efficient and simple way to fabricate a nanocomposite architecture of Co3O4/CNTs from carbon nanotubes (CNTs) and clusters of Co3O4 nanoparticles in deionized water. The crucial feature of the composite's structure is that Co3O4 nanoparticle clusters are uniformly dispersed and anchored to CNT networks in which Co3O4 guarantees high electrochemical reactivity towards sodium, and CNTs provide conductivity and stabilize the anode structure. We demonstrated that the Co3O4/CNT nanocomposite is capable of delivering a stable and high capacity of 403 mA h g(-1) at 50 mA g(-1) after 100 cycles where the sodium uptake/extract is confirmed in the way of reversible conversion reaction by adopting ex situ techniques. The rate capability of the composite is significantly improved and its reversible capacity is measured to be 212 mA h g(-1) at 1.6 A g(-1) and 190 mA h g(-1) at 3.2 A g(-1), respectively. Due to the simple synthesis technique with high electrochemical performance, Co3O4/CNT nanocomposites have great potential as anode materials for sodium-ion batteries.

This paper investigates the enhancement of the sensitivity and adsorption efficiency of a localized surface plasmon resonance (LSPR) biosensor that includes a layer of graphene sheet on top of the gold layer. For this purpose, biomolecular interactions of biotin-streptavidin with the graphene layer on the gold thin film are monitored. The performance of the LSPR graphene biosensor is theoretically and numerically assessed in terms of sensitivity and adsorption efficiency under varying conditions, including the thickness of biomolecule layer, number of graphene layers and operating wavelength. Enhanced sensitivity and improved adsorption efficiency are obtained for the LSPR graphene biosensor in comparison with its conventional counterpart. It is found that the LSPR graphene biosensor has better sensitivity with lower operating wavelength and larger number of graphene layers.

In this paper, 3-D finite element modeling and simulations are carried out to investigate the bending deformation of a single-walled carbon nanotube cantilever biosensor due to mass attached, and addition of a nano-scale particles to the beam tip resulting from the bioparticle detection. In addition, an algorithm for an electrostatic-mechanical coupled system is developed. The computed results are in excellent agreement with the well known electrostatic equations that govern the deformation.