Deakin Research

Institute for Frontier Materials

Membrane processes and novel separation materials design

The research into membranes at IFM has focused on tackling the chronic water shortage in Australia, aiming to develop novel nano-filtration membrane of high efficiency and high selectivity. We started research into new membranes including metallic, organic, inorganic, and composite membranes. The research has been enhanced with the commencement of the Collaborative Research Networks (CRN) program and through collaboration with Victoria University.

Novel membranes for water purification and gas separation

(Dr Li He, Dr Leonora Velleman, Dr Ludovic Dumée, Dr Fengshua She, Weiwei Cong, Bao Lin, Guang Wang, Prof. Lingxue Kong)

1-Metal membranes fabrication

  • Metal membranes offer great promise in separation due to their high chemical, radiation and mechanical resistance, enabling the purification of complex industrial liquid wastes.
  • The group investigates a number of techniques to fabricate advanced nano-porous and macro-porous metal membranes for use in liquid purification and desalination.

Electroless deposition of metals

  • Electroless deposition onto porous templates is a promising technique for fabricating metal membranes with small pore sizes (< 10 nm)
  • Our group has focused on the electroless deposition of copper, silver and nickel onto commercial membrane templates including nylon, alumina and polycarbonate and their application for micro and ultrafiltration. M

Schematic of electroless deposition of metals (here gold) on the surface of poly(carbonate) etched membranes. Metals are being deposited on the surface of the membrane and of its pores to form a semi-dense structure allowing for fine control of both pore size and porosity
(Velleman et al., Journal of Membrane Science, 2010; Dumée et al. Journal of Materials Chemistry, 2012)

De-alloying of metal thin films

Nano-porous gold membranes: Commercially available white gold leaves (50Au:50Ag) are de-alloyed to reveal a random network of pores (~ 20 nm in diameter). The de-alloyed gold films are ~100 nm thick allowing for fast transport across the membrane.

Porous copper membranes: Copper/zinc thin films were also de-alloyed to produce low cost nano-porous membranes. The zinc metal is preferentially etched away under reducing conditions and solubilized revealing the copper matrix of the alloy.

Scanning Electron Micrograph of a de-alloyed gold - silver ultra-thin leaf (100 nano-meter thick). Well-ordered pore arrays can be formed by removing the silver phase

Sintering and electro-spinning

Nano-porous metal membranes were also prepared from the sintering of mixed metal nano-particles with a sacrificial template leading to highly versatile porosities and pore size distribution. These thin porous layers were then sintered onto thicker metal nano-fibre meshes formed by the reduction of metal salts rich electrospun nano-fibres.

2-Polymeric membranes

Lyotropic liquid crystals self-assembled membranes

  • The use of lyotropic liquid crystals (LLC) as a template to form periodic nanostructures in polymer materials is a promising technology
  • Applications include gas and water filtration, biology, and health science
  • Highly ordered meso-structures can be prepared through block co-polymer self-assembly or in situ co-polymerisation.

Zhang, J, Xie, Z.L., She, F.H., Hoang, M., Hill, A. J. Gao, W.M. and Kong, L.X. (2011) J. Appl. Polym. Sci., 120(3), pp1817-1821

Zhang, J., Xie, Z. Hill, A. J. She, F.H., Thornton, A. W., Hoang, M. and Kong, L.X. (2012) Soft Matter, 8(7), 2087-2094

Templating block co-polymer matrixes to form arrays of well-defined hexagonal pores

3-Hybrid membranes

Metal organic frameworks hybrid membranes

The group is dedicated to the integration and continuous growth of metal organic frameworks (MOFs) into porous nano-structures, including carbon nanotube and metal substrates.

Through this work we are aiming to provide to the fragile and discrete MOF crystals strong and versatile templates for enhanced gas separation performance.

Ludovic Dumée, Li He, Matthew Hill, Bo Zhu, Mikel Duke, Jürg Schütz, Fengshua She, Huanting Wang, Stephen Gray, Peter Hodgson and Lingxue Kong (2013), J. Mat. Chem. A, In press)

Cross section Scanning Electron Micrograph of a composite carbon nanotube metal organic framework membrane

A composite carbon nanotube metal organic framework membrane.

Graphene and MOF based membranes for water purification

Recently, graphene oxide (GO) membranes have proven to be an excellent material for water filtration because they are completely impermeable to gases such as hydrogen while allowing unimpeded permeation of water vapour.
However, these membranes are fragile and cracks can develop easily since GO can readily disperse in water through solvation of surface carboxylic groups.
Polymer-based nano-composites have been the subject of increased interest in recent decades because of their enhanced properties arising from the reinforcement of fillers. The dispersion of the nano-fillers within the polymer matrix has significant influence on the properties of the composite.
Our group fabricates GO based composite membranes with excellent mechanical stability, high water flux and salt rejection.

Surface of a graphene oxide bucky-paper membrane. The graphene oxide sheets form nano-scale wrinkles on the material surface

Mixed matrix membranes

The development of synthesis methods for pinhole free, mechanically stable, inorganic-organic hybrid membranes that combine advantages of both inorganic and organic membranes, is attracting a great deal of interest.

We are developing these mixed matrix membranes (MMMs) by mixing different inorganic materials, such as carbon nanotubes, zeolite, grapheme and metal-organic frameworks into polysulfones, polyarylates, polycarbonates, poly(arylethers), poly(arylketones) and polyimides for gas separation and water purification. The goal of the project is to design and manufacture MMMs to improve gas or water flux while maintaining other properties.
(He et al, 2011 Nanoscale Research Letters 6(637)

Schematic of the formation of mixed matrix membranes prepared by polymer/nano-particle solvent casting. Water or gas molecules can diffuse at the interface between the polymer matrix and the nano-particles leading to enhanced flow membranes
Making a mixed matrix membrane using polymer/nano-particle solvent casting. Water or gas molecules can diffuse at the interface between the polymer matrix and the nano-particles to give a membrane with enhanced flow properties.

Membrane process development

Dr. Li He, Dr. Ludovic Dumée, Mr Bao Lin, Prof. Lingxue Kong

The group is investigating novel desalination technologies including capacitive deionisation, membrane distillation and membrane evaporation by using advanced functional graphene and metal membranes.

Micro and nano-porous materials characterisation with synchrotron technologies

Dr. Li He, Dr. Ludovic Dumée, Prof. Ling Xue Kong

The team is involved across a number of projects related to a number of Australian Synchrotron beamlines including powder diffraction, X-ray spectroscopy and small/wide angle X-ray scattering (SAXS/WAXS). Recent work demonstrated that SAXS can be used to characterise alignment of nano-particles, pore shape and distribution as well as resolving the diffusion mechanisms across micro-porous materials.

Ludovic Dumée, Kallista Sears, Stephen Mudie, Nigel Kirby, Chris Skourtis, Jill Mcdonnell, Stuart Lucas, Jürg Schütz, Niall Finn, Chi Huynh, Stephen Hawkins, Lingxue Kong, Peter Hodgson, Mikel Duke, Stephen Gray (2013), Carbon In Press

Ludovic F. Dumée, Kallista Sears, Jürg A. Schütz, Niall Finn, Mikel Duke, Stephen Mudie, Nigel Kirby, Stephen Gray (2013), J. of Coll. And Int. Sci. In press

Ludovic Dumée, Aaron Thornton, Kallista Sears, Jürg Schütz, Niall Finn, Steven Spoljaric, Robert Shanks, Chris Skourtis, Mikel Duke, Stephen Gray (2012) PNSMI 22(6) 673-683

Image analysis and 3D tomography for porous materials characterization

Dr. Fengshua She, Prof. Lingxue Kong

Modelling novel separation and fluid dynamics processes

Dr. Weimin Gao, Prof. Lingxue Kong

Deakin University acknowledges the traditional land owners of present campus sites.

16th August 2013