面對日益嚴重的溫室氣體排放與全球暖化議題，發展高效能的二氧化碳 (CO2) 轉化技術已成為緩解溫室效應與實現碳中和的關鍵策略。逆水煤氣轉換 (Reverse Water－Gas Shift， RWGS) 反應能將CO2 轉化為一氧化碳 (CO)，由於CO是費托合成 (Fischer–Tropsch synthesis) 等下游製程的重要中間體，使得RWGS反應成為極具前景的CO2 資源化利用途徑之一。然而，目前學術界對於如何構築高效的RWGS觸媒活性位點尚未達成共識，且驅動活性位點形成的微觀機制亦尚未明朗。為了突破此學術瓶頸並釐清微觀結構—效能關係，本研究分別利用膠體法、水熱法與沉澱法製備具不同結構特徵的CeO2 載體，隨後透過膠體法負載銅 (Cu) 奈米顆粒，成功獲得一系列Cu/CeO2 觸媒。催化活性測試結果顯示，藉由兩步驟膠體合成法製備的觸媒在400 °C下展現出優異的反應性能，其CO2 轉化率達11.61%，且對目標產物CO的選擇性高達100%。值得注意的是，結合 X 射線繞射 (XRD)、高解析穿透式電子顯微鏡 (HRTEM)、X 射線光電子能譜 (XPS)、電子順磁共振 (EPR) 與拉曼光譜 (Raman) 等表徵鑑定證實，該觸媒經過500 °C煅燒處理後，部分銅物種會擴散嵌入CeO2 晶格中以形成Cu－Ce固溶體結構，其餘銅物種則高度分散於載體表面。此獨特的Cu－Ce固溶體結構顯著增強了強金屬—載體交互作用 (SMSI) 並促進氧空位之生成，進而大幅提升CO2 的吸附與活化能力。整體而言，本研究證實透過膠體合成策略，可成功建構兼具高度分散銅物種與豐富活性位點之Cu/CeO2 固溶體觸媒，為下一代高效CO2 加氫轉化觸媒之設計提供了關鍵的科學依據與創新指引。;Driven by the urgent need to reduce carbon dioxide emissions， the development of efficient CO2 conversion technologies has become an important strategy for mitigating the greenhouse effect and achieving carbon neutrality. The reverse water gas shift (RWGS) reaction converts CO2 into carbon monoxide (CO)， which is an important intermediate for downstream processes such as Fischer–Tropsch synthesis， making it a promising route for CO2 utilization. However， a clear consensus has yet to be reached regarding how efficient active sites are created in RWGS catalysts. In particular， the exact mechanism driving their formation remains elusive. To overcome this scientific bottleneck and elucidate the structure－performance relationship， CeO2 supports with different structures were prepared using colloidal， hydrothermal， and precipitation methods. Cu nanoparticles were subsequently deposited via a colloidal approach to obtain a series of Cu/CeO2 catalysts. Catalytic tests showed that the catalyst prepared via the two－step colloidal synthesis method exhibited outstanding performance at 400 °C， achieving a CO2 conversion of 11.61% with 100% CO selectivity. Notably， comprehensive characterization via X-ray diffraction (XRD)， high-resolution transmission electron microscopy (HRTEM)， X-ray photoelectron spectroscopy (XPS)， electron paramagnetic resonance (EPR)， and Raman spectroscopy revealed that after calcination at 500 °C， part of the Cu species were incorporated into the CeO2 lattice to form a solid－solution structure， while the remaining Cu species were highly dispersed on the support surface. This structure enhances the strong metal–support interaction (SMSI) and promotes the formation of oxygen vacancies， improving CO2 adsorption and activation. Overall， this study demonstrates that a Cu/CeO2 solid－solution catalyst with highly dispersed Cu species and abundant active sites can be successfully prepared using a colloidal synthesis strategy， providing valuable insights for the design of efficient catalysts for CO2 hydrogenation.
