17 KB1821 KB17 KB200020242000Maček, JadranMarinšek, Marjanštevilka:1/2letnik:344 stranistr. 53-56ISSN:1580-2949COBISSID:213930URN:URN:NBN:SI:doc-3CD2E5CZslInštitut za kovinske materiale in tehnologijeMateriali in tehnologijegorivne celicekompozitni materialimikrostrukturaporoznostsol-gel postopkiPriprava poroznih kompozitnih materialov Ni-YSZ z mešanjem Zr(Cspodaj2Ospodaj4)spodaj2.xHspodaj2O in NiO-YSZ ter kasnejšo termično obdelavo| Porous Ni-YSZ composite material preparation by the mechanical mixing of Zr(Csub2Osub4)sub2.xHsub2O and NiO-YSZ and subsequent thermal treatment|Beside good electrocatalytical performances and mechanical stability at elevated temperatures it is essential that the anode composite material exhibits appropriate porosity and permeability to assure transport of the electrochemical process reactants and products. The anode layer with relatively high porosity was prepared by the mechanical mixing of NiO-YSZ and Zr(?$C_2O_4)_2$?.x?$H_2O$? and subsequent thermal treatment. Zr-oxalate hidrate during the thermal treatment decomposes and releases substantial amount of gases, e.g. ?$H_2O$?, CO and ?$CO_2$?. These gases form pores in the anode microstructure. The amount on Ni in the composite must remain under 52 wt.% to prevent its shrinkage during the reduction of NiO to Ni. Similarly Zr(?$C_2O_4)_2$?.x?$H_2O$? addition must be kept relaatively low because of out-coming gases can destroy the anode microstructureBistven mikrostrukturni pogoj za anodno plast v SOFC je, da ima poleg izraženih elektrokatalitskih lastnosti in stabilnosti pri obratovalni temperaturi tudi primerno poroznost in permeabilnost za transport reaktantov in produktov elektrokemijske reakcije. Anodno plast z relativno veliko poroznostjo smo pripravili z mešanjem NiO-YSZ in Zr(?$C_2O_4)_2$?.x?$H_2O$? terkasnejšo termično obdelavo kompozita. Zr-oksalat hidrat med termično obdelavo razpade do ?$ZrO_2$? ob izhajanju velike množine plinov (?$H_2O$?, CO in ?$CO_2$?). Izhajajoči plini v materialu oblikujejo številne pore. Delež Ni v kompozitu ne sme preseči 52%, ker v nasprotnem primeru, zaradi porozne strukture in s tem slabšega kontakta med ?$ZrO_2$? zrni, pride do spremembe dimenzij elektrode med redukcijo NiO do niklja. Dodatek Zr(?$C_2O_4)_2$?.x?$H_2O$? mora biti relativno majhen, ker lahko izhajajoči plini porušijo strukturo anodnega materialaTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaInštitut za kovinske materiale in tehnologije