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Information × Registration Number 0216U008254, 0116U004339 , R & D reports Title The investigation of the effect of excess manganese on properties formation of ceramic manganite (Nd0,67Sr0,33)1-xMn1+xO3 (x = 0; 0,2) to be used as the cathode of solid oxide fuel cells popup.stage_title Head Akimov Gennadiiy Yakovych, Registration Date 16-12-2016 Organization A.A. Galkin Physics and Engineering Institute of National Academy of Science of the Ukraine popup.description2 Objects of the study are ceramic manganites of (Nd0,67Sr0,33)1-xMn1+xO3 (x = 0 и 0,2) composition. The subject of the study is the structure, phase composition, electrical conductivity. The goal of the work is the investigation of the effect of excess manganese on phase composition, the microstructure and transport properties of (Nd0,67Sr0,33)1-xMn1+xO3 (x = 0; 0,2) ceramic manganites sintered at different temperatures to be used as the cathode of solid oxide fuel cells. Research methods are scanning electron microscopy, x-ray diffraction for the study of the microstructure and phase composition, the standard four-probe method for the study of transport properties, processing and analysis of the results. The investigation of the effect of excess manganese on the phase composition, structure parameters, grain size and density of the samples, the electrical conductivity at temperatures of 550-800 °C of (Nd0,67Sr0,33)1-xMn1+xO3 (x = 0 and 0,2) ceramic manganites after sintering at temperatures ranging from 800 to 1400 °C was performed. It is found that with increasing of the sintering temperature in the samples with x = 0 the lattice parameters of manganite phase are decreased, and after sintering at 1400 °C it is revealed the presence of two manganite phases with different content of Sr. In samples with excess manganese (x=0,2) the invariability of the lattice parameters and the stoichiometry of strontium content were recorded after sintering at all temperatures. The conductivity of ceramics with excess manganese on the average is five times higher the conductivity of ceramics without excess manganese in the temperature range 550-800 °C. It is discovered for the first time that only in the sample with x=0,2 sintered at 1000 °C the ceramics microstructure was formed with an open porosity of 20-30 %, the grain size of 0,25-0,5 mkm and conductive properties which meet the requirements of the cathode for the medium temperature ceramic fuel cells. Product Description popup.authors Новохацька Анастасія Олександрівна popup.nrat_date 2020-04-02 Close