目前連接板材料的選擇有陶瓷材料及金屬合金材料，兩者各有其優缺點，如陶瓷材料可運作在較高的溫度且抗蝕性及抗氧化性佳，而金屬材料的可加工性及製作成本則優於陶瓷材料；計畫結合上述兩種材料之優點，於金屬合金上連接板塗佈適用於SOFC的陶瓷材料。本研究團隊利用核能所提供之金屬連接板材Crofer22，發展陶瓷材料表面處理技術，以甘氨酸/硝酸鹽法(Glycine-Nitrate Process, GNP)製備La1-xCaxCrO3 (LCC)鑭系金屬氧化物進行塗佈。LCC具有很好的抗高溫氧化性、良好的導電性。利用不同燒結時間與溫度、陶瓷材料濃度、塗佈層厚度之製程條件，以強化連接板材的抗蝕性及抗氧化性，提高連接板材的性能及運轉時的耐久性，並分析不同製程所得材料之物化性質與導電性質。 本研究以XRD鑑定結果證明在金屬表面噴鍍La1-xCaxCrO3 (LCC)化合物，在高溫800 ℃且長時間之操作下可抑止金屬表面FeCr2O4氧化峰之生成。藉由SEM之分析得知LCC/Crofer22複合連接板之附著度良好且不脫落，進而証明LCC與Crofer22之熱膨脹係數相近，不會因熱膨脹而導致電池組件斷裂或剝離。本研究也利用比表面積電阻(ASR)測試陶瓷/金屬複合連接板之導電性能，原未塗佈之試片，經過長時間(82小時)氧化後，其ASR值由1.0361增加至3.0740 mΩ-cm2，但經塗佈後之ASR值可下降至0.9263 mΩ-cm2，證明塗佈後之複合連接板於高溫下操作可提升其導電度。 統合上述之研究成果，藉由合金表層批覆技術之開發，改善原合金材料之高溫特性，使陶瓷/金屬複合連接板在高溫運轉條件下，具足夠的化學穩定性，有效提升抗蝕性及抗氧化性且符合低成本等要求，以達到本研究計畫之目標。 Two choices for interconnect materials are ceramic and metallic alloy materials. To combine the advantages of these materials, we’ll coat high electronic conductivity ceramic materials, such as lanthanide series metal oxides (La1-xCaxCrO3, LCC). LCC powder materials were synthesized by the glycine-nitrate-process(GNP). Our study included different sintering times and temperatures, concentrations of coating ceramic materials, and thickness of coating. The effects of different test conditions are related to performance. From XRD results, longer sintering time could also induce the undesired formation of FeCr¬2O4. From SEM results, we clearly saw that the coating layer was quite smooth and the LCC20-coated Crofer22 composite was suitable as an interconnect in SOFC since it could prevent Cr from oxidation and volatilization at high internal temperatures under SOFC operation conditions. For ASR measurements, the ASR of fresh Crofer22 was measured at 1.0361 mΩ-cm2. After 100 hr oxidation, the result of non-coated sample was 3.0740 mΩ-cm2. With a similar setup to LCC20-coated samples, results were 0.9263 mΩ-cm2. These results improved the ability of the composite interconnect to promote electronic conductivity at high internal temperatures. Through comprehensive studies, we seek to develop ceramic/metal composite interconnect materials with low cost, high electronic conductivity, great high temperature characteristics, high oxidation resistance, puncture resistance, and stability under multiple chemical gases.
