Ni-CGO composite for SOFC anode

Composite anode has been synthesized by several methods, like combustion, solid state reaction [1-4]. In this work compounds of synthesized by polymeric precursors method. The composite NiO phases calcinated already. The materials were characterized by X ray diffraction and scanning electronic microscopy. The refi the diffraction data indicated that the powders were crystallized in sub micrometric characteristics. The composite produced showed good characteristics for the use as anode for SOFC. The direct use of natural gas makes the Solid Oxide Fuel Cell (SOFC) potenti with the current energy conversions technologies. The advantages over the High Temperature SOFC, which includes better thermal compatibility among components, fast start with lower energy CeO2 based materials are alternatives to the Yttria Stabilized Zirconia (YSZ) to application in SOFC, as they have higher ionic conductivity and less ohmic losses comparing to YSZ, and they can temperatures (500-800°C). These electrolytes based in ceria require special electrodes with a higher performance and chemical and termomechanical compatibility The production of this composite had some steps. At first phases, Ce0,9Gd0,1O1,95 and NiO, by polymeric precursors temperature was determined by prev mixtured in a 50-50 weight % proportion, powder was used to produce two pellets by pressing under 198 MPa and sintered at 1300 oC for 30 min. The mixture powder was characterized by XRD, Figure 1, and the data was refined usi method and the program BDWS-9807. The crystallographic results are in the Table 1. was thermal attacked to show it’s microstructure, and was analyzed by SEM, Figure 2. Another pellet suffered a thermal treatment with H2 by SEM to check if all the nickel had became metallic indeed. The XRD results confirmed the present only of the two crystalline phases. The SEM results of the first pellet shows that the phase dispersion didn’t happen in a nanometric scale, producing some agglomerate of phases. The analysis also proved that Table 1: Crystallographic data attained by Rietveld refinement of XRD a=b=c (Ǻ) d (Ǻ) Ce0,9Gd0,1O1,95 5,4180 1,7624 NiO 4,1760 1,6877 * Rp = 11,86 %; Rexp = 12,47 %, Rwp References [1] S. Zha, W. Rauch, M. Liu. Solid State Ionics, n. 166 (2004) pp. 241 [2] T. Ishihara et al. Solid State Ionics, n. 132 [3] V. Gil, C. Moure, J. Tartaj. Journal of the European Ceramic Society, n. 27 [4] C. Ding et al. Scripta Materialia, n. 60 (2009) pp. 254 [5] B. C. H. Steele. Solid State Ionics, v. 129 (2000) pp. 95 [6] A. Atkinson et al. Nature Materials, v. 3 (2004). Figure 1: NiO-CGO XRD diffractogram : Synthesis and Characterization , A. E. Martinelli, R. M. Nascimento and CP: 1524 Brazil. beacella@gmail.com. coprecipitation gadolinium-doped ceria, Ce0,9Gd0,1 Ce0,9Gd0,1O1,95 was attained by mixture of the wanted phases. All the produced powders had nanometric and Intermediate Temperature SOFC consumption, manufacture and operation cost reduction [6]. was to produced synthesis method and calcinated at 800 °C. This ious experiments. As a second step both by milling under 60 rpm rotation and 2 hours. Part of the mix atmosphere to reduce the NiO to metallic nickel and was also after treatment the NiO was reduced to metallic Ni. DXRD (nm) ε (%) Weight % U 45,84 0,0695 48,56 0,000000 47,82 0,0782 51,44 0,000000 = 16,25 % and S = 1,30. -250. (2000) pp. 209-216. (2007) pp. 4205-4209. -256. -110. Figure 2: SEM microscopy image of the sintered NiO-CGO pellet. C. A. Paskocimas – 59072-970 Natal, RN, , polymeric precursors, O1,95 (CGO) and NiO were the powders of the both nement of ally more competitive offer several [5]. The operate at lower nanopowders of the two phases’ powders were ng Rietveld The sinterized pellet analyzed