Abstract: Nanoscale carbon materials including tubes, sheets, and dots have interesting and, in many cases, unique optical, electronic, and thermal properties. We have been exploring these nanomaterials for various technologies, from bulk-separated metallic/semiconducting single-walled carbon nanotubes for electrical/electronic devices to carbon nanosheets for thermal and mechanical composites and carbon-based photoluminescent nanoparticles (?carbon dots?) as effective imaging-sensing agents and photocatalysts. In this talk, some interesting and representative recent results from our research will be highlighted.