A simple chemical technique has been developed to grow large quantity of carbon nanostructures, including carbon nanotubes, hydrocarbon nanotubes and carbon nanoonions, in the organic solution at ambient (room) temperature and atmospheric pressure using silicon nanostructures (nanowires, nanodots, ribbons, and porous silicon) as starting materials. These CNT and CNO have the lattice d-spacing from 3.4 .ANG. to 5 .ANG..