Carbon science in 2016: Status, challenges and perspectives

Several researchers share their perspective on the status and challenges faced by the carbon science in 2016. In addition to chemical vapor deposition (CVD) and hydrosolvo/thermal processes, alternative innovative growth techniques of these hypothetical 3D solids should now be a focus for carbon researchers. Recently, it has been demonstrated that graphene nanoribbons with specific diameters and nanotubes with desired helicity could be synthesized by careful polymerization of aromatic molecules. New theoretical studies using the nanotube/catalyst interface thermodynamics and the kinetic growth theories have widened the understanding of chirality selectivity towards near-armchair tubes. In 2013, a novel method based on aqueous-two polymer phase separation has emerged as an easily accessible and versatile approach for sorting nanotubes which is promising for low-cost scalable production of high-purity SWCNTs. Gel chromatograph based separation methods have also yielded high-purity single chirality optical isomers. New carbon materials are key components in alternative energy technologies that include electrodes for batteries, supercapacitors, fuel cells, and electrolytic cells for hydrogen production from water. They are also of interest as transparent conductors in solar cells, bipolar plates in fuel cells, lightweight materials that save energy in aircraft and automotive operations, and catalysts or catalyst supports for energy transformations that include carbon dioxide reduction into fuels and commercial chemicals.