Utilizing Highly Reactive Lewis Pairs Generated by Oxygen Vacancies in the Cu3Mo2O9 Solid Catalyst for Cycloaddition of CO2 to 1,2-Propanediol
This work emphasizes generating highly reactive Lewis pair sites on CuMo oxides for CO2 activation and utilization in the cyclization reaction to produce propylene carbonate from 1,2-propanediol. The CuMo oxides were synthesized by enabling the oxygen vacancies that enhance the catalytically active sites, resulting in the formation of metastable cations (Mo5+ and Cu1+) and oxygen vacancies. Under ethanol-PEG-400 medium, the pure phase of Cu3Mo2O9 obtained at 500 C exposed maximum defects without any secondary phase compared to other screened catalysts. The experimental and theoretical investigations provide evidence for determining and correlating the characteristics of active sites with catalytic performance. The catalysts were extensively characterized along with density functional theory (DFT) studies, which revealed the presence of defect centers as one of the key factors in the enhanced activity. From the chemical bonding analysis, i.e., Crystal Orbital Hamiltonian Population (COHP) and Electron Localization Function (ELF), the CO2 molecule is known to form a strong chemisorption interaction with the catalyst surface that is facilitated by the oxygen vacancy/Lewis pairs. The Cu-Mo oxide catalyst achieved 99% conversion of 1,2-propanediol and 97% yield of propylene carbonate, outperforming previously reported catalysts. Thus, Cu-Mo oxide was shown to be highly efficient catalyst with good recyclability for 1,2-propanediol and the CO2 reaction. 2025 American Chemical Society.
Sujith, S.; Vaishnavi, B.J.; Rajashekhar Vaibhava, K.M.; Sunajadevi, Kalathiparambil Rajendra Pai; Shanbhag, Ganapati V.
Inorganic Chemistry;Volume;64;Issue;25;pp.12473-12491
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https://doi.org/10.1021/acs.inorgchem.5c00316 https://www.scopus.com/pages/publications/105008060280?origin=resultslist
Sujith S., Materials Science and Catalysis Division, Poornaprajna Institute of Scientific Research, Bidalur, Devanahalli, Bengaluru, 562164, India, Center for Quantum and Computational Studies, Poornaprajna Institute of Scientific Research, Bidalur, Devanahalli, Bengaluru, 562164, India, Department of Chemistry, Christ University, Bengaluru, 560029, India; Vaishnavi B.J., Materials Science and Catalysis Division, Poornaprajna Institute of Scientific Research, Bidalur, Devanahalli, Bengaluru, 562164, India; Rajashekhar Vaibhava K.M., Materials Science and Catalysis Division, Poornaprajna Institute of Scientific Research, Bidalur, Devanahalli, Bengaluru, 562164, India, Center for Quantum and Computational Studies, Poornaprajna Institute of Scientific Research, Bidalur, Devanahalli, Bengaluru, 562164, India; Sunajadevi K.R.P., Department of Chemistry, Christ University, Bengaluru, 560029, India; Shanbhag G.V., Materials Science and Catalysis Division, Poornaprajna Institute of Scientific Research, Bidalur, Devanahalli, Bengaluru, 562164, India, Manipal Academy of Higher Education (MAHE), Manipal, 576104, India