Graphitized multi-walled carbon nanotubes, 99.9+% (OD: 30-50 nm, ID: 5-12 nm, Length: 10-20 um) are used in 1) Electromagnetic-wave absorption and shielding 2) Energy conversion 3) Lithium-battery anodes 4) Hydrogen storage 5) Nanotube composites (by filling or coating.