Effect of the addition of water on the preparation of pillared carbon from graphite oxide silylated by a two-step method

Pillared carbons were prepared from graphite oxide silylated by a two-step method using octyltrichlorosilane and then 3-aminopropylethoxysilane. When the second step reaction was performed at 110 °C, larger amounts of silylating reagent reacted with the concurrent reduction of graphite oxide. Addition of water in the reaction system during the second step reaction accelerated the reaction at a lower temperature as the result of the hydrolysis of ethoxy groups in 3-aminopropylethoxysilane to more active silanol groups. Microporous pillared carbons with interlayer spacings of around 1.55 nm and pore sizes less than 1 nm were obtained from the pyrolysis of the resulting silylated graphite oxides. The BET surface area increased with the increase in the amount of water added during the second step reaction and reached 500 m2/g.