00000ctm a22000004i 4500 UP-99796217611949629 Buklod 20160226104318.0 m |o d | ta 160226s2015 xx d r |||| u| (iLib)UPD-00254210257 DENG rda eng DMLUC LG 995 2015 E65 N86 Nunez, Gandy M. author. Fabrication and characterization of proton-conducting solid oxide electrolyte for fuel cell application thesis by Gandy M. Nuñez ; Rinlee Butch M. Cervera, adviser. Quezon City College of Engineering, University of the Philippines Diliman 2015. xiii, 131 leaves color illustrations 28 cm text rdacontent unmediated rdamedia volume rdacarrier Thesis (M.S. Energy Engineering)--University of the Philippines Diliman May 2015. Available to the general public. One of the promising materials for Intermediate Temperature (400-600°C) Solid Oxide Fuel Cell (IT-SOFC) is yttrium-doped Barium Zirconate (BZY) due to its high protonic conductivity and chemical stability. It can be synthesized via wet chemistry processes or solid state reaction. In this study, stoichiometric amounts of ZrO2, Y2O3, Ba(NO3)2, HNO3, citric acid and ethylene glycol were prepared to synthesize 20% mol V-doped BaZrO3 (BZY20) via a modified citrate-nitrate combustion wet chemistry process (Pechini Method). The obtained BZY20 sample has been fully characterized using XRD, TG/DTGIDT A, FTIR, Raman Spectroscopy and SEMIEDS. XRD results showed that for sample sintered at 1500°C, a single phase BZY20 was successfully synthesized. The calculated lattice parameter is 4.2100 A which is higher than the reported lattice parameter of a pure BaZr03 (BZ) at 4.1930A due to higher ionic radius of Y+3 as compared to Zr+4. Thus, yttrium has been successfully doped in the BaZrO3 perovskite structure. Morphological analysis revealed an average grain size of about 1um with relative density of about 95%. The electrolyte performance was evaluated by measuring the electrochemical impedance of BZY20 in dry, humidified and D2O argon gas flow environment at 400-600°C to investigate the protonic conductivity of the sample using a fabricated conductivity cell and testing set-up. A constant voltage perturbation of 10 mV was applied at a frequency range of 5MHz - 0.1 Hz. Results showed that the highest conductivity was attained at 600°C in humidified argon gas flow environment. The total conductivity values observed were 5.1Oxl0.5-5 Scm-1, 1.95xl0-4 Scm-1 and 1.59x10-4 Scm-1, for dry argon, humidified argon and D2O argon gas flow environment, respectively. Hence, in this study BZY20 was successfully synthesized via a modified Pechini method using a more readily available and cheaper raw materials and the material showed a total protonic conductivity promising as a solid electrolyte for IT-SOFCs. Solid oxide fuel cells. Solid state proton conductors. Cervera, Rinlee Butch M. adviser. FI UP UPD DENG-II LG 995 2015 E65 N86 Thesis