Study of effective factors on microstructure and properties of gel cost NiO/SDC composite as an anodes application in solid oxide fuel cell

The composite of Nickel Oxide-Samarium doped Ceria، NiO-SDC (Ce0. 8sm0. 2O1. 9)، is used as the solid oxide fuel cell anode. In this study، nanoparticles of NiO-SDC were synthesized through sol - gel combustion method using citric acid geling agent as a reducing agent (fuel) and metal nitrates as oxidants. The characteristics of the synthesized powder were analyzed through methods such as DTA/TG، XRD، BET and SEM. Then the porous parts (50:50 wt%) of NiO-SDC composite with open porosity of 64% were produced by gel-casting based on the help of agar gel. Agar was used due to non-toxicity and its ability in producing a strong gel. The composite was prepared as a stable suspension by combining NiO-SDC (50:50 wt%) in aqueous environment along with 3 wt% of DOLAPIX CE-64 as stabilizer and 2. 5 wt% of agar. The rheological behavior of suspension was studied through changing the percentage of the solid and the concentration of the geling agent. The optimum amount of DOLAPIX CE-64 was determined based on deposition and zeta potential. The phase composition and microstructure of sintered powder samples was studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Moreover، the distribution and porosity of the parts were determined through Mercury Porosimetry method.