【阡变陌化】COFs制备基本问题（一）：制备亚胺键COFs的催化剂

 制备亚胺键COFs的催化剂及其条件  

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一． CH₃COOH（乙酸）¹

首例亚胺键COFs以CH₃COOH作为催化剂制备。目前，乙酸依然是使用最广泛的制备亚胺键COFs的催化剂，优化反应条件通常包括调节催化剂的用量和浓度（3 M，6 M和9 M浓度乙酸水溶液最为常用）。

二．CH₃COOH + 调节剂（aniline as a modulator）²

  马天琼，王为教授等通过加入苯胺作为调节剂，调控亚胺键的生成速率，可以得到单晶亚胺键3D COFs。

三．CF₃COOH³

刘玉豪，崔勇教授等以CF₃COOH作为催化剂制备Fluorinated COFs 1，而Fluorinated COFs 2和Fluorinated COFs 3采用CH₃COOH作为催化剂。

四．对甲苯磺酸（p-toluenesulfonic acid）⁴

采用PTSA作为催化剂合成亚胺键具有挑战性，主要原因在于其酸性较强，只有部分亚胺键COFs可采取此方法合成。

The PTSA mediated solid-state mixing approach has opened up a new route for rapid, processable, and bulk scale production of highly crystalline porous COFs.

Owing to the intense acidic nature of PTSA (pKa = 2.8; water), the imine-linked COF crystallites, during the framework formation, readily decompose under the experimental conditions, leading a high extent of amorphization.

We made a prediction that the synthesis of imine-linked COFs using this approach can only be achieved by providing enough steric hindrance around the imine bonds or by incorporating significant hydrophobic environment to protect it from H⁺ and H₂O attack during the COF crystallization.

五、三氟甲磺酸金属盐（metal triflates）⁵

       William R. Dichtel发展了一种以三氟甲磺酸金属盐（metal triflates）为催化剂制备高结晶性亚胺键COFs的方法。相比与醋酸作为催化剂的长反应周期（>24 h）和高温（>70 °C），该方法显著提高了亚胺的形成和交换速率，在室温下仅需10 min即可得到高度结晶的COFs。研究发现Sc(OTf)₃效果最好。

六、金属卤化物（metal halides）⁶

PbBr₂, PbCl₂, PbI₂, SbI₃和BiBr₃

In conclusion, we demonstrated the catalytic activity of metal halides, specifically the lead and less toxic antimony and bismuth halides

Among the metal halides evaluated, SbI₃ was identified as the most efficient catalyst, which yields COFs within minutes with a high BET surface area

The COF matrices formed under metal halide catalysis were used for in situ perovskite synthesis. 原位合成COFs和钙钛矿的复合材料

七、三(五氟苯基)硼烷[tris(pentafluorophenyl)borane]⁷

催化剂不仅起到催化作用，还可以调节COFs的拓扑结构。Tris(pentafluorophenyl)borane was applied for the growth of imine COFs with hcb topology and varied in functional groups, as well as a new one, COF-820, with sql topology. All these COFs were obtained at room temperature. Their high crystallinity and porosity demonstrate the versatility of the organic Lewis acid as a catalyst. Bulky organic Lewis acid was found critical for the production of COF-820, while its absence resulted in the formation of a different COF, 4PE-1P-COF, with kgm topology using the same building blocks. Such steric effect, typical for organic catalysts, provides a new way to regulate the topology of COFs and their future design

The topology and pore size of COFs are known to be critical for their macroscopic applications

To further verify the role of organic Lewis acid in topology regulation, control experiment with the extra amount of aniline to quench the acidic site in TPFB. As the ratio of aniline increased, a mixed phase of two topologies emerged. The PXRD pattern showed multiple peaks, corresponding to the finger print peaks of both simulated sql and kgm structures. SEM images revealed two morphologies for the product obtained from this condition, rhombic sheet and spherical structures 。（通过SEM和XRD说明相的纯度）

八．过渡金属硝酸盐（transition-metal nitrates）⁸

Fe(NO3)3·9H2O, Ni(NO3)2·6H2O, Zn(NO3)2·6H2O, Mn(NO3)2·6H2O, Cu(NO3)2·6H2O和 Co(NO3)2·6H2O均可以作为催化剂制备亚胺键COFs，经研究发现，Fe(NO3)3·9H2O的效果最好。

九．苯甲酸⁹

合成步骤如下，用于制备二维单晶COFs。