Filter paper, loaded with catalyst precursor, is burned to generate catalyst nanoparticles for single-wall nanotube (SWNT) synthesis in a two-stage flame. A First-stage diffusion flame creates the Fe nanoparticles as an aerosol in the post-flame gases for catalysis. A second-stage flame is formed by the first-stage diffusion flame gases plus added fuel exiting into the combustion gases of a fuel-rich, premixed flame. Both catalyst conditioning and SWNT synthesis occurs within the post-flame reacting flow of this second-stage flame system.