> GOMD conference – May 2011 – Savannah (GA), USA

The Sol-gel session in the 2011 American Ceramic Society Glass and Optical Division Meeting organized by Gang Chen (Ohio University), in the afternoon of May 18 was a great success.

Detailed information on the five different talks

Prof. Rui Almeida of Instituto Superior Técnico and Prof. Lisa Klein of Rutgers University talked about their most recent work on sol-gel derived bio-glass and hybrid gels, receptively. Groups from the USA, France and Turkey also presented their work at the sol-gel session.

The first talk, on Sol-gel derived multi-porous glass scaffolds for bone regeneration (Invited), given by Rui M. Almeida (Instituto Superior Tecnico, Lisbon, Portugal), described the preparation of SiO2-CaO-P2O5 porous glass scaffolds by polymerization induced phase separation together with the sol-gel transition, which simultaneously exhibit interconnected nanopores in the range of ~ 5 – 30 nm and macropores ~ 20 – 300 μm. The characterization of such materials included physical, in-vitro (bioactivity) and in-vivo (New-Zealand rabbits) testing.

The second talk, on Organically Modified Siloxane Melting Gels (Invited), given by Lisa Klein et al. (Rutgers University, USA), dealt with the synthesis of new silica-based organic-inorganic hybrid nanocomposites obtained by combining a siloxane with one hydrolytically stable group (e.g. MTES) and a siloxane with two such groups (e.g. DMDES). This leads to melting gel behaviour for hybrids that are rigid at room temperature, but soften and flow around 150 ºC, for example.

The third talk, given by S. Dong and Gang Chen (Ohio University, USA), was concerned with Water Adsorption-induced Deformation of Micro- and Mesoporous Silica. Here, microporous and periodic mesoporous silica, synthesized by a sol-gel method using surfactants as structure-directing agents, were selected as model materials for the study of capillary action, by means of in-situ small and wide angle X-ray scattering, during water adsorption. Both reversible and irreversible structural changes were observed to be induced by the capillary action.

The fourth talk, given by B.A. Akgun, C. Durucan and Nathan P. Mellott (Alfred University, USA), on the Effect of silver incorporation on crystallization and microstructural properties of sol-gel derived TiO2 films, described a method to improve the photocatalytic and bactericidal properties of titania by doping with Ag nanoparticles. The structural and chemical properties of the Ag-TiO2 films were investigated by GIXRD, UV-Vis., XPS and Raman spectroscopies.

Finally, the last talk, given by X. Dieudonné et al. (CEA, France) on the Improvement of sol-gel optical stacking, described highly reflective coatings which were prepared using alternating layers of colloidal silica and zirconia. Particular attention was given to the processing and suspension parameters which led to thick coatings with higher critical thickness. Optical and mechanical characterization included ultra-nanoindentation, as well as laser surface acoustic wave and M-line spectroscopies.

Three posters from the session entered for the GOMD student poster competition. Very excitingly, two posters took the first and second place in the graduate student competition. C. Ihalawela (advisor G. Chen) from Ohio University won the first place for their work on liquid synthesis of phase-change memory materials, and H. Yavas (advisor C. Durucan) of Middle East Technical University (Turkey) won the second place for their work on silver incorporated indium tin oxide films.

Picture of the graduate student poster award ceremony (courtesy of American Ceramic Society) during the GOMD meeting. The 2nd on left is Ihalawela, and the 2nd on right is Yavas.

by Prof. Rui Almeida and Gang Chen

Further information on http://ceramics.org/2011-glass-optical-materials-division-spring-meeting