Regeneration of carbon nanotube and nanofibre composite film electrode for electrical removal of cupric ions

Low cost and large scale carbon nanotube and nanofibre (CNT–CNF) composite films have been fabricated and employed as electrodes for electrosorption of cupric ions. The regeneration of the saturated CNT–CNF film electrode has been investigated. Three methods (short-circuiting, short-circuiting and then reversing voltage, reversing voltage and then short-circuiting) are used for regeneration. The results show that low regeneration efficiency of CNT–CNF film electrode due to electrodeposition of Cu on the electrode surface can be highly improved by regeneration applying reverse voltage combined with short circuit. 93% regeneration efficiency can be achieved when 0.8 V reverse voltage is applied before short-circuiting during regeneration of CNT–CNF film electrode.