School of Materials Science and Engineering, Tianjin Key Laboratory of Metal and Molecule-Based Material Chemistry, National Institute for Advanced Materials, Nankai University, Tianjin, 300350, P.R. China.
Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry (Ministry of Education), College of Chemistry, Tianjin Normal University, Tianjin, 300387, P.R. China.
ChemSusChem. 2020 Feb 7;13(3):548-555. doi: 10.1002/cssc.201903018. Epub 2019 Dec 16.
The aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), a promising renewable monomer to produce bio-based polymers such as polyethylene furanoate (PEF), has recently emerged as the subject of increasing interest. Here, holey 2 D Mn O nanoflakes were obtained by a facile thermal treatment of a Mn-based metal-organic framework (MOF) precursor. The structural and morphological properties of the nanoflakes were characterized by powder XRD, FTIR, SEM and TEM to explore the formation process. It was inferred that the linker loss in the MOF precursor and the oxidation of the Mn cation induced by the heat-treatment in air were responsible for the formation of holey 2 D Mn O nanoflakes. The specific morphology and redox cycle of the Mn cation on the surface endowed the synthesized nanoflakes with promising performance on the selective oxidation. The obtained nanoflakes calcined at 400 °C (M400) afforded over 99.5 % yield of FDCA at complete conversion of HMF, which is superior to the catalytic activity of commercial Mn O and activated MnO . To our knowledge, Mn O exhibiting such a high performance on the aerobic oxidation of HMF to FDCA has not yet been reported. Based on the investigation of the experimental parameters, a plausible reaction mechanism was proposed.
5-羟甲基糠醛（HMF）氧化为 2,5-呋喃二甲酸（FDCA），是一种很有前途的可再生单体，可用于生产生物基聚合物，如聚呋喃甲酸酯（PEF），最近引起了越来越多的关注。在这里，通过简单的热处理 Mn 基金属-有机骨架（MOF）前体制备了具有孔 2D Mn O 纳米片。通过粉末 XRD、FTIR、SEM 和 TEM 对纳米片的结构和形态特性进行了表征，以探索其形成过程。推断 MOF 前体中的配体损失以及空气中热处理导致的 Mn 阳离子氧化是形成孔 2D Mn O 纳米片的原因。Mn 阳离子在表面上的特殊形态和氧化还原循环赋予了合成纳米片在选择性氧化方面的良好性能。在 400°C 下煅烧得到的纳米片（M400）在 HMF 完全转化的情况下，FDCA 的产率超过 99.5%，优于商业 Mn O 和活性 MnO 的催化活性。据我们所知，Mn O 在 HMF 有氧氧化为 FDCA 方面表现出如此高的性能尚未有报道。基于对实验参数的研究，提出了一种可能的反应机制。
