| 摘要: | 隨著工業發展和化石燃料使用的增加，二氧化碳排放量持續上升，導致全球
暖化和氣候變遷等問題。電化學二氧化碳還原反應(CO2RR)是透過碳捕捉、利用
與封存(CCUS)將CO2轉化為有價值燃料的重要策略。然而，CO2RR面臨了選擇
性不佳以及難以轉化為高價值C2產物的挑戰。
本研究中，通過添加ZnO和聚乙烯吡咯烷酮(PVP)的修飾，促進Cu催化劑
將CO2轉化為C2H4的能力，進而生產有用的燃料並同時實現碳中和。本研究分
成兩部分討論，第一部分研究了在CO2RR過程中，透過在Cu中添加ZnO，分
析其產物選擇性的變化。在-1.0 V(vs. RHE)下，Cu和ZnO的主要產物分別是C2H4
(FEC2H4=36.7%) 和 CO (FECO=76.3%)。Cu75-ZnO25/C (Cu/Zn = 3:1)之 FEC2H4顯著
提高，達到46.5%，相比純Cu增加了20%。然而，7小時後其FEC2H4下降了40%，
僅剩22%。結果表明，將Cu與能產生CO的ZnO結合，可以提高關鍵中間體
CO的局部濃度，從而增強C-C偶合動力學。
第二部分中，在催化劑合成時加入PVP可以抑制H2和CH4的生成，並同時
保持FEC2H4。Cu93-ZnO7/C-PVP 展示了顯著的穩定性。在-1.0 V (vs.RHE)，7 小
時後FEC2H4保持在與初始效能相近值(50.2%)。原位 X 光吸收光譜(in-situ X-ray
absorption spectroscopy)分析顯示，Cu93-ZnO7/C-PVP 的高 C2H4選擇性和穩定性，
歸因於在CO2RR 條件下由 PVP 保護而穩定 Cuδ+。因此，這提供了更多活性位
點，從而增強了C2H4選擇性。
總體而言，本研究強調了ZnO和PVP在提高Cu催化劑CO2RR選擇性和穩
定度的協同作用，為更高效的 CO2利用和更永續性的燃料生產技術開闢了新的
思路。
;With industrial development and the increasing use of fossil fuels, carbon dioxide
emissions have risen continuously, leading to issues such as global warming and climate
change. The electrochemical carbon dioxide reduction reaction (CO2RR) is a crucial
strategy for carbon capture, utilization, and storage (CCUS) of CO2 into valuable fuels.
However, CO2RR faces challenges due to its poor selectivity, and the difficulty of
conversion into high-value C2 products.
In this study, the CO2 – ethylene (C2H4) conversion of Cu catalysts is promoted by
ZnO addition and PVP modification to produce useful fuels and achieve carbon
neutrality simultaneously. The first part examines the change in product selectivity after
adding ZnO into Cu during CO2RR. At -1.0 V (vs. RHE), the main product of Cu and
ZnO is C2H4 (FEC2H4= 36.7%) and CO (FECO=76.3%), respectively. For Cu75-ZnO25/C
(Cu/Zn = 3:1), FEC2H4 significantly improves, reaching 46.5%, and representing a 20%
increase in FEC2H4 compared to Cu. However, after 7 hours, it experienced a 40%
decline, leaving the FEC2H4 at only 22%. The results show that by combining Cu with
ZnO, which generates CO, the local concentration of the key intermediate CO can be
increased, thereby enhancing the C-C coupling kinetics.
In the second part, polyvinylpyrrolidone (PVP) is introduced during the catalyst
synthesis to suppress H2 and CH4 products while maintaining FEC2H4. Cu93-ZnO7/C
PVP demonstrates remarkable stability. At -1.0 V (vs. RHE), the FEC2H4 maintains the
original value (50.2%) after 7 hours. In-situ X-ray absorption spectroscopy analysis
shows that the high C2H4 selectivity and stability of Cu93-ZnO7/C-PCP is attributable
to the stable Cuδ+ protected by PVP under CO2RR conditions. Consequently, this
provides more active sites, thereby enhancing ethylene selectivity.
Overall, the study highlights the synergistic effects of ZnO and PVP in enhancing
ii
the efficiency and stability of Cu catalysts for CO2RR, paving the way for more efficient
CO2 utilization and more sustainable fuel production technologies. |
