Although commercial membranes are well established materials for water desalination and wastewater treatment, modification on commercial membranes is still necessary to deliver high-performance with enhanced flux and/or selectivity and fouling resistance. A modification method with plasma techniques has been extensively applied for high-performance membrane production. The paper presents a mechanistic review on the impact of plasma gas and polymerization, at either low pressure or atmospheric pressure on the material properties and performance of the modified membranes. At first, plasma conditions at low-pressure such as plasma power, gas or monomer flow rate, reactor pressure, and treatment duration which affect the chemical structure, surface hydrophilicity, morphology, as well as performance of the membranes have been discussed. The underlying mechanisms of plasma gas and polymerization have been highlighted. Thereafter, the recent research in plasma techniques toward membrane modification at atmospheric environment has been critically evaluated. The research focuses of future plasma-related membrane modification, and fabrication studies have been predicted to closely relate with the implementation of the atmospheric-pressure processes at the large-scale.
A new liquid plasma method is used to fabricate a Co3O4/CNT nanocomposite anode using a nanosecond pulse atmospheric pressure for sodium-ion battery application.
Controlled surface modification of boron nitride nanotubes has been achieved by gentle plasma treatment. Firstly, it was shown that an amorphous surface layer found on the outside of the nanotubes can be removed without damaging the nanotube structure. Secondly, it was shown that an oxygen plasma creates nitrogen vacancies that then allow oxygen atoms to be successfully substituted onto the surface of BNNTs. The percentage of oxygen atoms can be controlled by changing the input plasma energy and by the Ar plasma pre-treatment time. Finally, it has been demonstrated that nitrogen functional groups can be introduced onto the surface of BNNTs using an N(2) + H(2) plasma. The N(2) + H(2) plasma also created nitrogen vacancies, some of which led to surface functionalization while some underwent oxygen healing.
16 August 2012 in The Journal of Physical Chemistry C
Desired wettability has been achieved on highly hydrophobic boron nitride nanotube (BNNT) films using nitrogen/hydrogen (N2/H2) gas plasma treatments under controlled input energies and modes. Both hydrophilicity (contact angle (CA) ∼60°) and superhydrophilicity (CA < 5°) are demonstrated on BNNT films with little change of the surface morphology or the structure of individual BNNTs. The combination of continuous wave and pulse mode (CW+P) plasma shows more effective wettability modification and introduces more amine functional groups than the continuous wave (CW) plasma alone at a given input energy. (Super)hydrophilic/hydrophobic patterns have been created on BNNT films using masked plasma methods. The cell response to BNNT films is investigated for the first time. The proliferation of human primary mammary fibroblasts and a transformed mammary cell line (TXP RFP3) shows that the untreated hydrophobic BNNT films can support the growth of both cell lines, but the plasma treatments greatly enhance (up to six times) the number of cells attached to the surface of BNNT films.
1 February 2013 in Composites Part A: Applied Science and Manufacturing