本研究利用溶液燃燒法製備鈣鐵氧化物(CFO)與鈣鐵氧化物/鎂鐵氧化物(CFO/MFO)接面奈米粉末光觸媒，藉由調整不同的後處理溫度與氧化物與燃劑之比例(φ)，以及加入硝酸銨，製備不同樣貌之CFO(CFO-φ)以及CFO/MFO(CFO-Mg-φ與CFO-Mg-N-φ)異質接面結構之粉末光觸媒。不含鎂純相之CFO-0.6表面型貌為聚集之顆粒狀，進行連續式系統之光還原二氧化碳測試結果顯示，純CaFe2O4光觸媒活性甚低，無法偵測到產物。而含鎂之CFO-Mg系列粉末光觸媒，隨著φ質的提升，顆粒的分散性增加。於連續式系統之光還原二氧化碳中，以CFO-Mg-0.6為光觸媒時之主要產物為CH4及C2H4O，產量分別為1.1 μmol/g/h及0.66 μmol/g/h。透過HR-TEM分析可知，CFO-Mg-0.6由 CaFe2O4、少量Ca2Fe2O5及Mg2Fe2O4所組成。以硝酸銨輔助製備CFO-Mg-N粉末光觸媒，隨著φ值提升，表面型貌從片狀聚集，變為顆粒堆疊狀。CFO-Mg-N-0.48 (C2H4O產量為0.14 μmol/g/h)具有CaFe2O4、Mg2Fe2O4及Ca4Fe9O17。相較於CFO-0.6與CFO-Mg-N-0.48，CFO-Mg-0.6光還原二氧化碳效率明顯提升之結果，我們推測CaFe2O4/ Mg2Fe2O4接面之形成，可能為光催化二氧化碳轉換效能顯著提升之關鍵。

Calcium ferrites powders and calcium ferrite/magnesium ferrite heterostructured powders have been synthesized using solution combustion method. Fuel/oxidizer ratio and the amount of NH4NO3 influence the phases of calcium ferrites.
No product was detected over CFO-0.6 which possesses pure CaFe2O4 phase for CO2 conversion in the continuous system. Nevertheless, the formation of C2H4O is detected in the batch system with a yield of 0.1 μmol/h/g.
The yields of CH4 and C2H4O over CFO-Mg-0.6 which is mainly composed of CaFe2O4 and Mg2Fe2O4 are 1.1 μmol/h/g and 0.66 μmol/h/g, respectively.
Only C2H4O is acquired from CO2 photoconversion over CFO-Mg-0.4 (0.09 μmol/h/g) and CFO-Mg-N-0.48 (0.14 μmol/h/g) which consist of CaFe2O4 /Ca2Fe2O5 / Mg2Fe2O4 and CaFe2O4 /Ca4Fe9O17 /Mg2Fe2O4 , respectively.

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