Carbon doped MO–SDC material as an SOFC anode

Oxide mixtures MO–SDC, M = Cu, Ni, Co, SDC = Ce0.9Sm0.1O1.95 were synthesized by employing a citrate/nitrate combustion technique. Two kinds of Carbon materials, activated carbon (AC) and vapor grown carbon fiber (VGCF) were homogeneously dispersed into the MO–SDC. The materials can be used as anodes to fabricate single cells using a uniaxial die-press method. The sintering temperature was studied to optimize cell performance. Experimental results showed that cells sintered at 700 °C had better performance. When the temperature was above 750 °C, the cells were severely distorted, and cannot be tested. Compared with the basic MO–SDC anode, AC and VGCF improve the solid oxide fuel cell (SOFC) anode properties, due to a change of the microstructures of the anode materials which enhance their electron conductivity. Single cell performances were evaluated by I–V measurements, and when 1.25 wt.%VGCF was introduced into the MO–SDC by ball-milling, termed: 1.25 wt.%VGCF–MO–SDC, the 1.25 wt.%VGCF–MO–SDC anode material could achieve the highest power density of up to 0.326 W cm−2 with H2 as fuel. The calcination temperature of the MO–SDC dry gel also strongly influenced the electrochemical performance of the 1.25 wt.%VGCF–MO–SDC material. XRD spectra for each calcined temperature and the I–V measurement both suggest that calcinations at 550 °C for 1 h are suitable. 1.0 wt.%AC–MO–SDC and 1.25 wt.%VGCF–MO–SDC have similar performance when the cell was fed in methanol/3%H2O, and the corresponding power density was up to 0.253 W cm−2. Traces of carbon were found in the off-gases.