| Cathodes and solid electrolytes used for intermediate temperature solid oxide fuel cell(SOFC) were prepared by urea combustion method. Single fuel cell fed with20%H2S+80%N2 was studied, referring preparation and electrical performance of the cell,response characteristic of H2S in the anode compartment.Three cathodes (LSCF1, LSCF2, LSCF3) with perovskite structure were prepared.The conductivity was improved by increasing temperature within 400℃～850℃, whiledecreased when the temperature higher than 850℃. And the conductivity of three cathodesis in following order: LSCF2＞LSCF1＞LSCF3. The maximum conductivity of themobtained at 850℃was 150.68S·cm11, 89.26S·cm-1, 46.24S·cm-1 respectively.The electrolytes (BCZY, CCZY, SCZY) with perovskite structure were prepared. Theconductivity sequence of them is BCZY＞SCZY＞CCZY. And the conductivity was.improved by increasing temperature within 500℃～950℃. The maximum conductivity ofBCZY was 10-2S·cm-1 within 500℃～750℃. It indicated that three electrolytes withperovskite structure were proton conductor by Concentration Cell Method.The single fuel cell having the configuration of H2S, (CoS-Mo2S)/BCZY/LSCF2, airwas studied at atmospheric pressure and 80mL·min-1. The output voltage decreased withthe increase of the current density. Ohm Polarization was the chief cause of the voltage lossThe cell performance was improved by increasing temperature. The highest OCV 0.72Vwas obtained at 800℃with the maxmum current density 35.93mA·cm-2 and the maxmumpower density 5.61mW·cm-2, while 0.55V, 13.00mA·cm-2, 13.00mA·cm-2 at 600℃.The main products of the SOFC fed with H2S were H2O and S. The directelectrochemical conversion of H2S was the main reaction in the anode compartment, whilethe continuous reaction, which composed of thermal decomposition of H2S andelectrochemical conversion of H2, was side reaction. |
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