As a graduate student at FU Berlin, he studied structural end electronic properties of surfaces, including reconstruction and photoemission spectra.

[12] His computational studies of growth regimes of silicon[13] and carbon[14] clusters have made use of the semi-quantitative Linear Combination of Atomic Orbitals (LCAO) or tight-binding method.

[6] During his 1994 sabbatical stay at the laboratory of Richard E. Smalley, he turned his interest to the unique properties of nanotubes formed of carbon (CNTs) and other materials.

[24][25] In the following years, he has continued identifying applications of carbon nanotubes and two-dimensional materials in fields including low-resistance contacts to nanostructures,[26][27] nanomechanical energy storage,[28] and purification and desalination of water.

In 2008 he received the Japan Carbon Award for Life-Time Achievement and was chosen by the American Physical Society as member of the Outstanding Referees Program[33] for excellence in peer review.