The Co(II) metal–organic framework (MOF) {[Co(μ₃-L)(H₂O)]·0.5H₂O}_n (1, H₂L = thiazolidine 2,4-dicarboxylic acid) with rich Lewis acid sites was used as a catalyst for the conversion of CO₂ and propylene oxide into propylene carbonate with a yield of up to 98% under 50 °C and 1 atm. 1 exhibited excellent reusability, which could be regenerated easily for at least five runs without a decrease in the yield. Importantly, we synthesized two types of nano-crystals (N1 and N2) of 1 with polyvinylpyrrolidone (PVP) and hexadecyltrimethylammonium bromide (CTAB) as surfactants, respectively, and investigated their catalytic properties in comparison with that of 1 in the powder phase. A significant enhancement in both catalytic efficiency and product yield was observed when 1 was nano-crystallized. This is the first investigation about the relationship between the morphology and the catalytic parameters of MOFs. The results showed a strategy for efficiently applying MOFs as catalysts towards CO₂ conversion, which could also be used in other MOF-catalyzed processes.

中文翻译：

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通过Co（ii）金属-有机骨架 将CO ₂转化为环状碳酸酯，并通过纳米结晶提高了催化活性†

联合（II）的金属-有机骨架（MOF）{[CO（μ ₃ -L）（H ₂ O）]·0.5H ₂ ö} _Ñ（1，H ₂ L =噻唑烷-2,4-二羧酸）与富含路易斯酸的位点被用作催化剂，用于在50°C和1个大气压下将CO ₂和环氧丙烷转化为碳酸亚丙酯，产率高达98％。1型具有极好的可重复使用性，可以轻松再生至少五次，而不会降低产量。重要的是，我们合成了两种类型的纳米晶体（N1和N2）的1分别以聚乙烯吡咯烷酮（PVP）和十六烷基三甲基溴化铵（CTAB）作为表面活性剂，并研究了它们在粉末相中的催化性能（与1相比）。当1被纳米结晶时，观察到催化效率和产物产率的显着提高。这是关于MOF的形态与催化参数之间关系的首次研究。结果表明有效地将MOF用作催化剂以实现CO ₂转化的策略，该策略也可用于其他MOF催化的过程。