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DOE OSTI · 1827100

Highly Perfluorinated Covalent Triazine Frameworks Derived from a Low-Temperature Ionothermal Approach Towards Enhanced CO 2 Electroreduction

Suo, Xian·Zhang, Fengtao·Yang, Zhenzhen·Chen, Hao·Wang, Tao·Wang, Zongyu·Kobayashi, Takeshi·Do-Thanh, Chi-Linh·Maltsev, Dmitry·Liu, Zhimin·Dai, Sheng
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Abstract

Perfluorinated covalent triazine frameworks (F-CTFs) have shown unique features and attractive performance in separation and catalysis. However, state-of-art F-CTFs synthesized via the ZnCl 2 -promoted procedure have quite low fluorine contents due to C-F bond cleavage induced by chloride (a Lewis base) and the harsh conditions deployed (400-700 °C). Fabricating F-CTFs with high fluorine contents (> 30 wt%) remains challenging. Herein, we present a low-temperature ionothermal approach (275 °C) to prepare F-CTFs, which is achieved via polymerization of tetrafluoroterephthalonitrile (TFPN) over the Lewis superacids, e.g., zinc triflimide [Zn(NTf 2 ) 2 ] without side reactions. With low catalyst loading (equimolar), F-CTFs are afforded with high fluorine content (31 wt%), surface area up to 367 m 2 g -1 , and micropores around 1.1 nm. The highly hydrophobic F-CTF-1 exhibits good capability to boost electroreduction of CO 2 to CO, with faradaic efficiency of 95.7% at –0.8 V and high current density (–141 mA cm -2 ) surpassing most of the metal-free electrocatalysts.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYCO2 electroreductionLewis superacidcovalent triazine frameworkfluorinatedionothermal procedure

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Suo, Xian, Zhang, Fengtao, Yang, Zhenzhen, Chen, Hao, Wang, Tao, Wang, Zongyu, Kobayashi, Takeshi, Do-Thanh, Chi-Linh, Maltsev, Dmitry, Liu, Zhimin, Dai, Sheng. 2021-09-28. Highly Perfluorinated Covalent Triazine Frameworks Derived from a Low-Temperature Ionothermal Approach Towards Enhanced CO 2 Electroreduction. https://doi.org/10.1002/anie.202109342

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