Structure- and Composition-Controlled Synthesis of Carbon Nanotubes from Metal–Organic Frameworks

Synthesis of nanostructures derived from metal–organic frameworks (MOFs) has provided a route to design and prepare carbon-based nanomaterials, especially the synthesis of multilevel structures and assemblies. However, there is still a lack of investigations on the structure- and composition-controlled synthesis of MOF-derived carbon nanotubes (CNTs). Here we report a universal and straightforward method to prepare CNTs and nitrogen-doped CNTs (NCNTs) with controllable structural parameters from a single MOF precursor. Benefiting from the pyrolysis characteristics of the MOF precursor, selective N-doping was achieved by pyrolyzing the mixed-ligand MOFs via a controllable deposition process of the decomposed N-containing ligands during the growth process of CNTs. A series of growth conditions were investigated to reveal their effects on the structural parameters of CNTs. It was found that the growth temperature and the holding time both play key roles in the distribution of diameter and wall thickness of CNTs. And the photothermal conversion properties of the CNTs were also investigated, which showed a photothermal conversion efficiency of 58.4%.