Clay platelets are separated from an agglomeration of clay platelets by treating with cobalt acetate and leaving cobalt particles on the platelets. Carbon nanotubes are grown on the platelets at the cobalt sites, and the nanotubes separate platelets from the agglomeration. The separated platelets and nanotubes are acid cleaned. Intumescent fire retardant materials are chemisorbed on the clay platelets and nanotubes.