Probing the microstructural evolution of polyviologen-silica hybrid nanopowders during intermediate processing using X-ray microtomography

Gundogdu Ö. , Jenneson P. M. , Tuzun U., Gray G. M. , Hay J. N.

APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, cilt.85, ss.317-324, 2006 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 85 Konu: 3
  • Basım Tarihi: 2006
  • Doi Numarası: 10.1007/s00339-006-3700-3
  • Sayfa Sayıları: ss.317-324


Polyviologen polymers are potential template agents for hydrolytic sol-gel processing of silica particles. The resultant polyviologen-silica hybrid nanopowders are amorphous aggregates of roughly spherical shape, which can be harvested from the sol-gel solution and processed to green body products under different environmental conditions. A bench-top X-ray microtomography system, with a spatial resolution of 5 mu m is used to produce three-dimensional images of the dynamic processing of the nanopowders. Various processing routes are imaged using a custom built environmental chamber where the temperature, atmospheric pressure, and compaction force can be controlled. This allows processes such as vacuum sintering and microwave sintering to be studied. The three-dimensional images reveal the axial and radial distributions of the molten polyviologen polymer within a matrix of agglomerates of the silica nanoparticles. Such observations are crucial to the optimisation of the processes that are used to produce the green body products so as to preserve desirable nano-intensive properties.