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Abstract：
Selective oxidation of methane to organic oxygenates over metal-organic frameworks (MOFs) catalysts at low temperature is a challenging topic in the field of C1 chemistry because of the inferior stability of MOFs. Modifying the surface of Cu-BTC via hydrophobic polydimethylsiloxane (PDMS) at 235 °C under vacuum not only can dramatically improve its catalytic cycle stability in a liquid phase but also generate coordinatively unsaturated Cu(I) sites, which significantly enhances the catalytic activity of Cu-BTC catalyst. The results of spectroscopy characterizations and theoretical calculation proved that the coordinatively unsaturated Cu(I) sites made H2O2 dissociative into •OH, which formed Cu(II)-O active species by combining with coordinatively unsaturated Cu(I) sites for activating the C-H bond of methane. The high productivity of C1 oxygenates (CH3OH and CH3OOH) of 10.67 mmol gcat.-1h-1 with super high selectivity of 99.6% to C1 oxygenates was achieved over Cu-BTC-P-235 catalyst, and the catalyst possessed excellent reusability.
摘要：
在低温下通过金属有机骨架（MOF）催化剂将甲烷选择性氧化为有机含氧化合物是C1化学领域的挑战性课题，因为MOF的稳定性较差。通过疏水性聚二甲基硅氧烷（PDMS）在235°C下在真空下修饰Cu-BTC的表面不仅可以显着提高其在液相中的催化循环稳定性，而且还可以产生配位不饱和的Cu（I）位点，显著提高了Cu-BTC催化剂的催化活性。光谱表征和理论计算的结果证明，配位不饱和Cu(I)位点使H2O2解离成·OH，通过与配位不饱和的Cu（I）位点结合以激活甲烷的C-H键，形成了Cu（II）-O活性物质。10.67mmolgcat的C1含氧化合物(CH3OH和CH3OOH)的高产率。在Cu-BTC-P-235催化剂上实现了-1h-1，对C1含氧化合物具有99.6％的超高选择性，催化剂具有优异的可重复使用性。
