School of Resources & Environment and Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, Nanchang University, Nanchang 330047, China; Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, Southeast University, Nanjing, 210096, China.
School of Resources & Environment and Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, Nanchang University, Nanchang 330047, China.
Bioresour Technol. 2024 Aug;406:131001. doi: 10.1016/j.biortech.2024.131001. Epub 2024 Jun 17.
Oxygen vacancies (Ov) in metal oxides play a crucial role in modifying the electronic and acidic properties of catalysts, thereby influencing their catalytic activity. This study explores the impact of Ov in MnOx catalysts on their acidic and catalytic properties for the Meerwein-Ponndorf-Verley reduction of levulinic acid (LA) and levulinate to γ-valerolactone (GVL). Various characterization techniques demonstrate that surface Ov significantly modulate the acidic properties of MnOx catalysts, positively correlating with Lewis/Brønsted acid ratio and GVL yield. In situ DRIFTS and DFT calculations further unveil the reaction mechanism, revealing that Ov facilitate the activation and dehydrogenation of isopropanol and subsequent hydrogen transfer and hydrogenation of LA, leading to enhanced GVL production. These insights underscore the pivotal role of Ov in MnOx catalysts for the efficient conversion of LA to GVL, highlighting their importance in improving catalytic performance.
金属氧化物中的氧空位（Oxygen vacancies，Ov）在改变催化剂的电子和酸性性质方面起着至关重要的作用，从而影响其催化活性。本研究探讨了 MnOx 催化剂中的 Ov 对其酸性和催化性能的影响，用于 Meerwein-Ponndorf-Verley 还原乙酰丙酸（Levulinic acid，LA）和乙酰丙酸酯制备 γ-戊内酯（γ-Valerolactone，GVL）。各种表征技术表明，表面 Ov 显著调节 MnOx 催化剂的酸性，与 Lewis/Brønsted 酸比和 GVL 产率呈正相关。原位 DRIFTS 和 DFT 计算进一步揭示了反应机制，表明 Ov 有利于异丙醇的活化和脱氢以及 LA 的随后的氢转移和加氢，从而提高 GVL 的生成。这些结果强调了 Ov 在 MnOx 催化剂中对于高效将 LA 转化为 GVL 的关键作用，突出了它们在改善催化性能方面的重要性。
