Researchers in the Department of Chemistry and Biochemistry have developed a novel graphene nanoribbon synthesis, which have numerous applications in electronic devices.
Graphene nanoribbons (GNRs), narrow strips of graphene <10 nm in width, are promising new materials for the replacement of silicon in field-effect transistors (FETs), the principal devices behind nearly all modern electronics. Investigations into the uses of GNRs are currently limited by the lack of controlled and scalable synthetic methods. Current methods either employ top-down or bottom-up approaches, but neither has been able to synthesize GNRs in an inexpensive, controllable way with high yield. Top-down syntheses provide high material throughput but produces mixtures and cannot achieve widths below 10 nm. Although bottom-up approaches, either on-surface or in-solution, have excellent control over the structure, the yield is low and requires high-cost equipment and conditions or the yield is high but requires transition metal catalysts and in-solution oxidation, respectively. Large-scale synthesis of GNR with inexpensive procedures is vital to this material being used in electronic devices.
Researchers led by Professor Yves Rubin at UCLA have developed a novel and simple three-step bottom-up GNR synthesis in the solid-state under mild temperatures. The resulting GNRs have a well-defined width (~1.36 nm) and bandgap (1.4 eV) in addition to being electrically conductive. This method can used to controllably synthesize a large variety of GNRs with programmable sizes and electrical properties. This new synthetic approach is well suited for electronic device fabrication processes because it only requires UV light or heating, and no external chemical reagents. Likewise, this material can be readily patterned and directly formed on any substrate. This material will have versatile applications in many electronic devices, such as FETs, solar cells, and energy-storage devices.
TheGNRs have been controllably synthesized with defined widths and features. Both the chemical and morphological properties of the GNRs have been extensively studied. Additionally, the electrical conductivity of the material has also been probed and FETs have been constructed and tested.
Graphene nanoribbons, solid-state synthesis, bottom-up, tunable bandgap, electronic device fabrication, field-effect transistors, solar cells, energy-storage devices