To pursue a sustainable society, there is an urgent need of having energy-efficient devices with green processes. To effect this change, materials design plays a key role in supporting new emerging technologies. For example, hybrid & hierarchical structures could give scientists the ability to create specifically tailored nanocomposites that combine the advantages of each material constituent to enhance functionality. This talk summarizes current efforts on the design, synthesis, and characterization of carbon materials and their applications in water treatment, public health, and energy areas.