Abstract:
Hydrogenated carbon relates materials, such as graphene and diamond, has been regarded as promising candidates for applications in digital nanoelectronic devices.[1] This is because the electronic and chemical properties of these materials can be modified upon hydrogen adsorption and desorption.[2,3,4] However, fine-tuning the electronic properties and achieving precise control over the reactivity at the local scale still remains challenging. Scanning tunneling microscopy (STM) is an ideal tool to investigate the structure and electronic properties of interfaces. In addition, it also affords atomic-scale control of hydrogen desorption via tip-assisted modification.[5] In this talk, I will review two examples of using STM tip-assisted dehydrogenation to study fundamental hydrogen adsorption and desorption mechanisms. This technique was applied to hydrogenated graphene nanoribbons (GNRs), where an STM tip was positioned above hydrogenated features to induce site-specific dehydrogenation. By combining bond-resolved scanning tunneling microscopy (BRSTM) imaging with tip-induced dehydrogenation, the hydrogenation mechanism is studied in details.[6] Furthermore, this technique was also applied to hydrogenated diamond surfaces, where the STM tip serves as a precise engineering tool for conducting hydrogen depassivation lithography (HDL), which allowing to create local reactive sites for the deposition of nitrogen carrier molecules, as shown in Figure 1. By demonstrating the ability to create local reactive sites with atomic-scale precision on diamond surfaces, this work paves the way for atomically precise fabrication of qubits in diamond.[7]