Laboratory of Inorganic and Physical Chemistry
The main activity of the research group of Inorganic and Physical Chemistry is the study of environmentally friendly, chemical methods to the synthesis of high-tech, nanostructured inorganic materials.
A water based sol-gel method is developed and optimized successfully for the preparation of ferroelectric, piezoelectric, conductive and dielectric metal oxide powders and thin films (with thicknesses from several hundreds down to a few nm), which are strategically important for future developments in nanoelectronics. These materials have applications in for instance MOSFETs, DRAM, non-volatile memories such as flash or FERAMs, MEMS (micro-electromechanical systems), biosensors and transparant electrodes. The aim here is to achieve high-quality properties at the lowest possible processing temperatures.
Furthermore, the research group is also developing research activities concerned with preparation, via hydrothermal routes and microemulsion methods, and application of metal oxide nanomaterials:
1) Porous nanocrystalline ZnO and TiO2 films as well as ordered one-dimensional ZnO and TiO2 nanostructures with controlled geometry, for hybrid and dye-sensitized solar cells.
2) Metal oxide nanoparticles with a well defined morphology for photocatalysis, UV protection, antifouling applications, etc.
3) More fundamental nanoscientific and nanotechnological challenges such as the deposition of ultrathin uniform films and substrate based ordered nanopatterns
A great deal of attentation is paid to chemical synthesis aspects as well as chemical-structural characterization of starting, intermediate and finished products. These characteristics are related to the morphological, functional (electrical, electro-optic,...) and other properties of the material systems as they should be applied, which provides the research with an interdisciplinary character.
The research group of Inorganic and Physical Chemistry has at its disposal an elaborate set of analysis techniques for the characterization of intermediates and finished products. Techniques used on a daily basis are: Thermogravimetry (TGA), possibly coupled on-line to mass- (TGA-MS) and infrared spectrometry (TGA-FTIR) to study the outgassing of samples, applied for instance to the identification of functional groups and unraveling the mechanisms in the decomposition of the precursors to the final product. High temperature diffuse reflection (HT-DRIFT) provides complementary information on the chemical structure of the decomposing precursor, while in-situ high-temperature XRD (HT-XRD) allows the (trans)formation of crystalline oxide phases. Other FTIR based methods, which are frequently used are transmission FTIR, (attenuated total reflectance) ATR and grazing incidence ATR for thin films.
Nanoparticles are characterized by zeta-potential measurements and particle size distribution analysis using dynamic light scattering (DLS). Techniques for crystallographic and morphologic characterization are XRD, XRR (X-ray reflectometry), AFM (atomic force microscopy), SEM (scanning electron microscopy), cryogenic and cross sectionTEM (transmission electron microscopy) which are available at the Institute for Materials Research. Starting from 2010 a deep UV-micro Raman triple spectrometer will be taken into use for the characterization of a broad spectrum of precursors and (nano)materials.
By participation into projects and networks, less conventional techniques such as EXAFS (extended x-ray absorption fine structure) and neutron diffraction are available as well.
The research group is part of the Institute of Materials Research. The research is carried out in close collaboration with IMEC (Interuniversitair Micro-elektronica Centrum), the independent research center in nano-electronics and nano-technology situated in Leuven. Furthermore, direct involvement of industrial partners in the research is ensured in several research projects (link below). The group is a partner in different Flemish, national and international research projects and networks.