Clay/carbon nanocomposites as precursors of electrode materials for lithium-ion batteries and supercapacitors

Chars prepared by pyrolysis of organic precursors (Indoine Blue, Safranine, Pyrene) in the interlayer space of taeniolite were used as electrode materials in lithium/carbon cells. Due to oxidation of interlayer carbon by the silicate host, they contain a high amount of surface groups. and their essentially mesoporous character is attributed to the space liberated by the elimination of the clay template. A large reversible capacity for lithium insertion, up to 900 mAh/g, was detected for these materials. The chars presented a high capacitance which could reach 85 F/g in KOH electrolyte if they were formed below 850 degrees C. Such a high value relatively to the low BET surface area of the chars is strictly related to the important mesopore volume and to the rich surface functionality.