Sumio Iijima studied at the University of Electro-Communications in Tokyo and completed his PhD in physics at Tohoku University in Sendai before moving to Arizona State University in Phoenix, Arizona. In post-doctoral research and later as a research scientist from 1970 to 1982, he worked on high-resolution electron microscopy. Iijima revealed the first electron micrograph showing atoms in a crystal. He developed a new electron microscope that could view the structure of materials at the atomic level. In 1977, he achieved a long-term goal of electron microscopy when he was able to observe individual tungsten atoms. He carried out electron microscopy of graphite while working as a visiting scholar at Cambridge University in 1979.
Iijima moved back to Japan in 1982. He has been a Research Fellow at NEC Corporation since 1987 and published his seminal work on carbon nanotubes in 1991. Although carbon nanotubes had previously been observed, his paper generated unprecedented interest and stimulated a great deal of further research in the field.
Iijimas has been a Professor at Meijo University in Nagoya, Japan since 1999. He has received close to three dozen awards and prizes for his research including the Asahi Award in 1996, the Agilent Technologies Europhysics Prize in 2001, and the McGroddy Materials Prize in 2002 from the American Physical Society, as well as the Benjamin Franklin Medal in Physics, also in 2002.