Study Of The Performance And Preparation Of YSZ Electrolyte Membrance By Dip-Coating

Solid oxide fuel cell(SOFC),which can convert chemical energy into electrical energy directly, is attracting more and more attentions because of their high-energy conversion efficiency, low pollution, and fuel flexibility. From the viewpoint of cost reduction and long-term stability, many researchs have paid their attentions to fabrication of SOFC operationg at reduced temperature(600-800℃). Reducing the thickness of YSZ electrolyte is an effective approach to lower the operation temperature fo SOFC while to retain the high performance. Development of cost-effective fabrication technology of thin film electrolyte is a key step for fabrication of SOFC.We have discussed about the process of preparation electrolyte film via dip-coating. Dip-coating technology were developed to fabricate Y2O3-stabilized ZrO2(YSZ) electrolyte thin films onto NiO-YSZ porous anode substrates. The important technological parameters, which influence significantly the characterization of the dip-coating YSZ electrolyte thin films, including particle size and particle size distribution of the starting YSZ powder, composition of the dip-coating ink, sintering temperature of the dip-coating YSZ green films and dip times were investigated in detail. In the research, the compositions and the dosages of electrolyte slurry by sedimentation experiment and viscocity test, contains 8g YSZ(40nm) powders, 22mL the mixture of MEK/EtOH (11/11) as the solvent, 2mL triethanolamine as the dipersant and 0.32g PVB as the binder and 0.3g/0.3g DBP/PEG as the plasticizer. The prime slurry viscosity is 10·8 Pa.s. The fine time of dryness is about 7h. The TG-DSC testing is to determine sintering temperature of ceramic: sintered at 900℃for 24h and at 1300℃for 36h. The result of SEM imnting, we find that dip-coating method is suitble to fabricate electrolyte film. In addition, this way own some merits such as operation easy, period short of experiment. We fabricated function layer via dip-coating and electrophoretic deposition, The research results make know electrophoretic deposition excels dip-coating in fabricating anode gradient aspect, and max power density of electrophoretic deposition function layer is 320mW/cm2.The cell assembled with Ni-YSZ/YSZ/Pt system has a maximum power density of 0.33W·cm-2 and an OCV of 1.073V at 800℃, which is comparable to the theoretical value of 1.2V.