Design, synthesis and characterisation of coordination and organo-metallic compounds for fine chemical applications. (Ref Dr. Laura Crociani)
The increasing request for materials with new and/or improved properties and the need to control their compositional and structural homogeneity and reproducibility, by means of new eco-friendly synthesis routes, require high molecular precursors availability. Physical and chemical properties of the new precursors need to fit the material preparation procedures, also allowing the compatibility between reaction requirements and physico-chemical and functional properties of the target material.
In this regard, the obtained results were and are mainly related to the synthesis and reactivity evaluation of new coordination compounds (alkoxides, β-diketonates, amides) and organo-metallic (alkyls and cyclopentadienyls) of different elements (Al, Ca, Cr, Mg, Hf, Si, Ti, W, Zr, Zn) to be used as precursors for the preparation of oxide-based ceramic materials (Al2O3, CaO, Cr2O3, MgO, SiO2, WO3, TiO2, ZrO2, HfO2, ZnO).
The preparation of mixed and binary oxides with specific stoichiometry was also studied by means of the synthesis of “single-source” precursors. These hetero-bimetal complexes, which contain the required metals such as [(R2AlOSi(CH3)3]n, Co[Al(OiC3H7)4]2, LaCo(OC(CH2CH3)2CH2OCH3)5), were employed for the production of mixed oxides as Al2O3-SiO2, CoAl2O4 e LaCoO3.
Further research results have concerned the synthesis optimisation of:
- Calcium alkoxides with solubility in organic commercial solvents for the preparation of solutions for nano-layer deposition as protective and reinforcing coating for stone-based materials;
- Silver and platinum precursors for the Ag and Pt depositions;
- Hafnium and zirconium organo-metallic compounds as catalysts in olefin polymerisation reactions;
- Mg(BH4)2 synthesis for hydrogen storage application or to be used as precursor for MgB2 deposition.
Di-iminic ligands were recently developed starting for example from para-phenylenediamine derivatives acting as a molecular bridge between aldeheydic moieties. The reactivity of these new compounds with nickel salts was evaluated and the related complexes were tested as catalyst of olefin polymerisation , and as electro-catalysts of the activation of carbon dioxide
Deposition and characterisation of multi-functional layers by vapour phase chemical methods (CVD) of ceramic materials mono and multi-element, with specific mechanical, electrical, self-cleaning and catalytic properties. (Ref Dr. Rosalba Gerbasi)
The research activity aims to optimise the Metal Organic Chemical Vapour Deposition (MO-CVD), Plasma Enhanced Chemical Vapour Deposition (PE-CVD) and Atomic Layer Deposition (ALD) processes for the production of poly-functional coatings with specific mechanical, optical, electrical, catalytic, self-cleaning and bio-compatibility properties. The obtained coatings are also characterised with respect to composition, structure, morphology and functionality, with special care to the technological transfer of the obtained results.
As known, the Chemical Vapour Deposition – CVD technique is a very versatile deposition process and allows the preparation of different materials with specific composition and structure. At present, CVD is having a remarkable development for the preparation of materials with new and/or improved functional characteristics and it is able to satisfy the increasing request for high-specialised and poly-functional materials.
The research is dedicated to the deposition of oxide-based ceramic which are widely employed in electronics, photonics, surface protection and catalyst thanks to their specific physical and chemical properties. The obtained results concerned the optimisation of the processes for obtaining:
- Al2O3, Cr2O3, HfO2, SiO2, TiO2 and ZrO2 as protective mono and multi-layers coatings (anti-wear, anti-tarnishing for gold and silver industries, etc.);
- SiO2 on glass bottle for pharmaceutical packaging and process upscale to industry;
- TiO2 (also with doping elements) and photocatalytic properties evaluation for pollutants remediation;
- ZrO2 for energetics and tribological applications.
Furthermore, the research group is skilled in the deposition of metallic layers (i.e. silver and platinum) for decorative or electrodic purposes. The researchers are competent in the bottom-up material preparation by hybrid organic-inorganic methods, by means of the realisation of micro-and nano-structured polymeric templates with high specific surface and the following thin oxide film deposition via ALD (starting from commercial and home-made precursors). The products can be potentially employed in photovoltaics, photocatalytic, sensors etc. fields.
The research group actively collaborates with the paduan enterprise RT srl Unipersonale since 2015. RT srl Unipersonale is a company highly qualified in precision micro-parts for biomedical application since the end of Nineties (http://rtmedical.it). The collaboration aims to increase the bioactivity and the osteointegrative properties of dental implants. In order to obtain the desired improvement, the research study pursues a new synergic approach, developed in two consecutive steps. The first one leads to the deposition of TiO2 layer, while in the second one calcium phosphate precursors are deposited. Despite the wide specialized literature concerning this topic, the innovation proposed and tested by ICMATE and RT srl Unipersonale appears original. The collaboration always takes into account the requirement of an innovative approach, joint to the need of an easy technological transfer to the industry.
The collaboration is object of a patent application.
On the whole, the research group boasts many national and international collaborations and it is involved in research projects also carried out with SME partners to transfer the obtained results from the laboratory scale to the industrial production. In the ICMATE history, the research activity related to the industrial requirements has trained the researchers in improving their ability to work synergically in order to reach the best solution to the proposed problems.