Enhancing Efficiency and High‐Value Chemicals Generation through Coupling Photocatalytic CO2 Reduction with Propane Oxidation

• Published in: ChemSusChem Vol. 17; no. 15; pp. e202301881 - n/a
• Main Authors: Duan, Zitao, Lv, Ruiqi, Huang, Zongyi, Li, Jiwei, Xiao, Xiaohong, Zhang, Zhaoxia, Wan, Shaolong, Wang, Shuai, Xiong, Haifeng, Yi, Xiaodong, Wang, Yong, Lin, Jingdong
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 12.08.2024
• Subjects: Carbon dioxide; carbon dioxide reduction; Chemical reactions; Coupling; coupling reaction; Electrons; Hydroxyl radicals; Oxidation; Photocatalysis; Propane; propane selective oxidation; Propylene; Solar energy conversion; Substitution reactions; titanium dioxide
• ISSN: 1864-5631; 1864-564X; 1864-564X
• DOI: 10.1002/cssc.202301881

Conversion of CO2 into high‐value chemicals using solar energy is one of promising approaches to achieve carbon neutrality. However, the oxidation of water in the photocatalytic CO2 reduction is kinetically unfavorable due to multi‐electron and proton transfer processes, along with the difficulty in generating O−O bonds. To tackle these challenges, this study investigated the coupling reaction of photocatalytic CO2 reduction and selective propane oxidation using the Pd/P25 (1 wt%) catalyst. Our findings reveal a significant improvement in CO2 reduction, nearly fivefold higher, achieved by substituting water oxidation with selective propane oxidation. This substitution not only accelerates the process of CO2 reduction but also yields valuable propylene. The relative ease of propane oxidation, compared to water, appears to increase the density of photogenerated electrons, ultimately enhancing the efficiency of CO2 reduction. We further found that hydroxyl radicals and reduced intermediate (carboxylate species) played important roles in the photocatalytic reaction. These findings not only propose a potential approach for the efficient utilization of CO2 through the coupling of selective propane oxidation into propylene, but also provide insights into the mechanistic understanding of the coupling reaction. In the photocatalytic CO2 reduction reaction, oxidation of water involves complex multi‐electron processes, presenting significant challenges. However, substituting water oxidation with the selective oxidation of propane can yield remarkable enhancements in CO2 reduction, up to fivefold, while also yielding valuable propylene.