| 摘要: | 本研究主要透過使用固態反應法製備高溫固態離子導體氧化釔鐿摻雜鈰鋯酸鋇(BCZYYb)粉體，再以膠體製程技術之旋轉塗佈法在NiO/YSZ 複合材基板上製備其鍍膜，並研究 BCZYYb 鍍膜樣品的各項性質。經固態反應法合成的粉體分別使用以X 光繞射儀(XRD)分析其結晶相變化、雷射粒徑分析儀對煆燒粉體進行粉體粒徑分析、阿基米德法進行密度測量分析與熱處理後的收縮情況分析；鍍製完成的鍍膜樣品經不同熱處理後，以掃描式電子顯微鏡(SEM)對鍍膜進行微結構的分析、低略角XRD 分析鍍膜層的相變化、以交流阻抗儀(EIS)對鍍製樣品進行電性分析。從研究結果可以發現，經過在1300 oC 的煆燒後，粉體開始初步形成鈣鈦礦的結晶相，當煆燒溫度超過1500 oC 時，主要結晶相為單一相鈣鈦礦結構，從上述結晶相的分析可以得知，BCZYYb 的結晶相會隨著溫度的上升與燒結持溫時間的拉長越趨於單一相。SEM 微結構的觀察結果表明，當溫度上升至1500 oC 時，BCZYYb 粉體鍍膜會形成相對緻密的鍍膜結構，並有顯著的晶粒成長現象，其中濃度為5 wt%的懸浮液鍍製樣品具有相對緻密的鍍膜，並從微結構分析中得知，當懸浮液濃度達到5 wt%時，可以達到對基板近乎完全的披覆，但鍍膜中仍存有少量的孔洞，膜厚約為3.4 µm。經過二次鍍膜後的樣品，鍍膜中的孔洞明顯消除，膜厚約為5.7 µm。電性分析的結果顯示，於空氣(氧氣)環境下，BCZYYb 單次鍍膜與二次鍍膜的樣品導電度相近，導電度在 600 oC 下分別為2.070 與1.139 S/cm，800 oC 下為8.496 與4.126 S/cm，整體活化能分別為0.622eV 與0.680 eV，可以認定高溫導電現象由BCZYYb 鍍膜層所主導；於氫氣環境中，由於鍍膜層存在缺陷，使鍍膜樣品的導電度均遠低於質子導電的標準需求，此時單次與二次鍍膜樣品的導電度在600 oC 下分別為0.01583 與0.00030 S/cm，800 oC 下為0.01935 與0.00045 S/cm，整體活化能分別為0.098 eV 與0.180 eV，可以認定高溫導電現象由基板所主導。另外，NiO/YSZ 基板於1050 oC 的預燒結後，密度約為2.76 g/cm3，經過1550 oC 二次燒結後，基板密度為6.29 g/cm3。
In this study, BaCeZrYYbO3 (BCZYYb) powder were prepared by a solid-state reaction method, and the BCZYYb coating samples were prepared by a colloidal coating process on the NiO/YSZ composite substrate. Kinds of properties of the coating samples were also analyzed. The powder synthesized by the solid-state reaction methods were analyzed by X-ray diffraction spectrometer (XRD), laser particle sizer, Archimedes method, shrinkage analysis, Scanning Electron Microscope (SEM), and electrochemical test station. The results of powder analysis show that after calcination at 1300 oC, the perovskite phases were formed , and when the calcination temperature exceeds 1500 oC, the crystalline phases are mainly pervoskite. The SEM microstructure observation shows that BCZYYb coating samples were with a dense and continuous coating structure from the suspension concentration of 5 wt% after heat treatment at 1500 oC. But there are still a few holes found on the surface of BCZYYb coating layers. The film thickness is about 3.4 µm. After 2nd cycle coating process, the coating sample shows less holes in the coating layers. The film thickness after 2nd coating is about 5.7 µm. The results of electrical analysis show that in the air (oxygen) environment, the electrical conductivities of BCZYYb single coating and 2nd cycle coating samples are similar, the conductivity is 2.070 and 1.139 S/cm at 600 oC, and 8.496 and 4.126 S/cm at 800 oC, the overall activation energy is 0.622 eV and 0.680 eV respectively, it can be concluded that the high temperature conductive phenomenon is dominated by BCZYYb coating layer; in the hydrogen environment, due to the defects of the coating layer, the conductivity of the coated samples is much lower than that of the proton The standard requirements for electrical conduction. At this time, the electrical conductivity of the single and 2nd cycle coating samples are 0.01583 and 0.00030 S/cm at 600 oC, 0.01935 and 0.00045 S/cm at 800 oC, and the overall activation energy is 0.098 eV and 0.180 eV, it can be concluded that high temperature conductivity is dominated by the substrate. In addition, the density of NiO/YSZ substrate is about 2.74 g/cm3 after presintering at 1050 oC and 6.29 g/cm3 after secondary sintering at 1550 oC. |
