ZIF-derived porous carbon nanofibers for high-efficiency capacitive deionization
【Abstract】As an environmentally-friendly and energy-saving desalination technology, capacitive deionization (CDI) is becoming an important desalination technology to replace reverse osmosis desalination and electrodialysis desalination. Carbon-based materials have been applied as promising CDI electrodes. However, most of them are powdered and binders are inevitably employed in the process of electrode fabrication, which causes a decline in electrosorption ability. Herein, monolithic porous carbon nanofibers with a flexible structure were synthesized by electrospinning and carbonizing the mixture of zeolitic imidazolate frameworks (ZIFs) and polyacrylonitrile (PAN). Due to the hierarchical porous structure and hydrophilicity, the as-synthesized porous carbon nanofibers exhibit a great salt adsorption capacity of 19.92 mg/g in 500 mg/L NaCl solution under the voltage of 1.2 V, which is over two times that of pristine carbon nanofibers.
【Keywords】 capacitive deionization; carbon nanofibers; electrospinning; desalination; electrochemistry; adsorption;
(Translated by LIU YS)
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