| Summary: | 碩士 === 國立東華大學 === 材料科學與工程學系 === 103 === This aim of this study is to prepare Ce1-xBixO2-y(x=0.05~0.2) solid electrolytes by pulsed laser deposition (PLD),which is operating at intermediate temperature (500℃~700℃) for solid oxide cells (SOFC).This study hope to develop BDC and expect to replace the traditional YSZ. Bi-doped CeO2 was prepared by the ceramic target, which contain the CeO2 and Bi2O3.The pulse laser source wavelength of 355nm Nd：YAG laser. The high energy laser interact on target surface and become ionzed gas, the CeO2 and Bi2O3 will form a solid solution and deposit on Si/Ti/Pt substrates. Bi-doped CeO2 thin film growth is controlled by changing the substrate temperature, deposition time and doping concentration.
The results showed all BDC thin film with (111) preferred orientation at pulse energy 70mJ/pulse. The XRD (111) peak shift to low angle, it means the lattice of CeO2 expand, the Ce4+ is replaced by Bi3+(Ionic radius：Bi3+ > Ce4+).Among the doping concentration, the Ce0.95Bi0.05O1.975 (B5DC) thin film which deposit 10 hours(1490nm) exhibited the highest conductivity about 4.13×〖10〗^(-8) S/cm at 700℃ and the activation energy is found to be 0.6041eV. At the same doping concentration, the thin film which deposit 10 hours exhibited highest conductivity, B20DC(1303nm)、B15DC(1165nm)、B10DC(1624nm), 9.27×10^(-9) S/cm、9.95×10^(-9) S/cm、6.18×10^(-9) S/cm.
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