DEPARTMENT of Solid State Electrolytes

Head: Prof. Tamara Petkova

Tel.: (+359 2) 872 43 39; 979 27 67

E-mail: tpetkova@bas.bg

Research of new amorphous and polycrystalline ion conductive materials is carried out. The aim is to synthesize new original materials, exhibiting high ionic and mixed conductivity for application in solid state ionic devices, e.g. primary and secondary batteries, fuel cells, gas sensors, electrochromic displays, pacemakers, etc. A specific property of these materials is the possibility of continuous composition variation. This ensures variation in their inherent isotopic properties and utilization  as bulk materials, powders  and thin films. Systems with active  components Li, Na, Ag and Cu and oxide (silicate, borate, phosphate, sulfate, chromate, etc.), halide and mixed oxide-halide or halide-chalcogenide systems are under investigation. Investigations on glass and crystalline phase formation regions and the structure of various systems are carried out. Via the use of diffraction methods as well as optical and impedance spectroscopy a correlation between the composition, structure and properties of the obtained materials is found.

A wide number of chalcogenide and chalco-halide glasses, including those containing silver are studied. They possess high ionic conductivity at room temperature. Silver can be involved in the glassy matrix in many ways and this leads to a great variety in the properties of these glasses. The study includes thin films of chalcogenide glasses containing silver and iodine or silver iodine.

Synthesis of catalysts containing Pt or non-noble metals

Projects

Investigation of new glassy materials for application in electrochemical systems.

Head: Assoc. Prof. Tamara Petkova, financially supported by the Ministry of Education – Greek-Bulgarian bilateral agreement – X1206

The purpose of the project is to obtain glasses (chalcogenide, oxide) with properties competitive to materials usually used for electrochemical devices manufacturing.

 The project ' objectives are: selection of the compositions, synthesis and  preparation of  thin films, determination of the physical and  electrochemical characteristics and investigation of the possibility of the  structures’ application  as elements  in electrochemical systems.

Membrane cell hydrogen genarator and electrocatalysis for water splitting

Head: Assoc. Prof. Evelina Slavcheva, financially supported by EC  ICA-CT-2002-100001

The main aim of the project is the development of a novel  type membrane cell hydrogen generator which is based on recent achievments and expirience in PEM fuel cells and imposes as a target to provide both a compact electrolyzer design and construction and highly electro-catalically active electrodes, thus resulting in a rather low voltage at high current densities. Production of catalytic nanostructured  materials, their screening, for  initial activity for the hydrogen and oxygen evolution and chemical and structural analysis are the objectives of our work.