低溫燃料電池H2-PEMFC系統中之氫氣燃料來源，通常由碳氫化合物或甲醇先藉蒸汽重組或部分氧化及自熱重組反應再經水氣轉移反應產生，此程序產生之富氫氣體混合物典型含有0.3~1%的一氧化碳，其必須被去除或將濃度降至100 ppm以下，以免毒化電池中常用之陽極Pt觸媒。選擇性優先氧化(PROX)是去除CO的較簡易可行方法，合適的CO選擇性氧化觸媒必須具有高CO氧化活性，相對於氫氣被氧化要有高選擇性，且需考量高濃度二氧化碳及水氣對CO選擇性氧化的負面影響。有許多金基與鉑基觸媒已被用來選擇性氧化CO，但這些貴金屬觸媒都不能避免氫氣被明顯氧化的損耗。本實驗室已於前期研究中發現，CeO2擔體中引入少量的ZrO2不僅能促進擔體Ce0.9Zr0.1O2的redox特性，且能增進CuO/Ce0.9Zr0.1O2觸媒對CO的選擇性氧化能力，最佳觸媒7%CuO/Ce0.9Zr0.1O2具有取代貴金屬觸媒用於燃料電池PROX單元中移除CO的潛力，最近發現CeO2中引入SnO2製得之Ce1-xSnxO2共氧化物redox特性更佳，更利於CO選擇性氧化。本計畫擬於CeO2中引入不等量Sn4+ 製備Ce1-xSnxO2共氧化物，探討Ce1-xSnxO2共氧化物的redox特性與CuO/Ce1-xSnxO2觸媒於富氫中的CO選擇性氧化，開發出更適合燃料電池低溫選擇性氧化CO 之高性能CuO/Ce1-xSnxO2觸媒。 Hydrogen, used as a fuel in H2-PEMFC systems, is generally generated from hydrocarbons or methanol by steam/autothermal reforming or partial oxidation, followed by a water-shift reaction. Typical effluents from such a process contain 0.3–1% of CO in an excess of H2. Carbon monoxide must be removed or reduced to below 100 ppm to avoid poisoning of the anode electro-catalysts for use in PEMFC. Preferential CO oxidation in hydrogen (PROX) appears to be the simplest and most effective method for removing CO. The most important requirements of catalysts used for selective oxidation are a high oxidation rate of CO and a high selectivity with respect to the side oxidation reaction of H2. Such catalysts should also be able to tolerate the presence of CO2 and H2O. Numerous Au-based and Pt-based catalysts have been studied on the selective oxidation of CO. But none of these noble catalysts can prevent significant losses of hydrogen by oxidation. Our previous work have found that an appropriate amount of ZrO2 introduced into cerium oxide not only promoted the redox property of the resulted mixed-oxide Ce0.9Zr0.1O2 but also enhanced the selective oxidation of CO on CuO/Ce0.9Zr0.1O2. The best catalyst of 7%CuO/Ce0.9Zr0.1O2 is a promising candidate for replacing noble catalysts used in a PROX unit of H2-PEMFC system for removing CO. Recently we also found the mixed oxide of Ce1-xSnxO2 used as a support was better than CexZr1-xO2 for the selective oxidation of CO. This work will introduce Sn4+ into CeO2 to form Ce1-xSnxO2 mixed oxides, and their redox properties and the selective oxidation over CuO/Ce1-xSnxO2 catalysts will be examined. This work aims at developing a highly effective CuO/Ce1-xSnxO2 catalyst for CO selective hydrogenation in a H2-rich gas mixture, under a low temperature for fuel cells. 研究期間：9601 ~ 9612
