Fullerphene Nanosheets: A Bottom‐Up 2D Material for Single‐Carbon‐Atom‐Level Molecular Discrimination

Ultrathin 2D nanoporous materials offer enhanced sensitivity and high spatial resolution in sensing applications making them important for the selective discrimination of guest molecules. Here bottom‐up fabrication is reported of a novel molecularly‐thin nitrogen‐doped 2D fullerphene. Thermal annealing at 700 °C of a bottom‐up assembled fullerene C60‐ethylenediamine (EDA) thin film results in formation of a nitrogen‐doped ultrathin carbon film, fullerphene, which exhibits a hierarchically micro/mesoporous structure at its surfaces. N‐doping of fullerphene is dominated by pyrrolic and quaternary nitrogen atoms, which allow selective and repetitive adsorption and desorption of low‐molecular‐weight carboxylic acid vapors through noncovalent interactions. The large surface area (655.2 m2 g–1) and pore volume (0.659 cc g–1) offered by the hierarchical micro/mesoporous architecture leads to superior sensitivity of fullerphene to formic acid over acetic acid in the vapor phase demonstrating that novel 2D fullerphene provides an attractive platform for the discrimination of carboxylic acids at the single‐carbon‐atom level. A bottom‐up technique has been used to prepare 2‐dimensional molecularly‐thin nitrogen‐doped film material, fullerphene nanosheet. The N‐doped hierarchically micro‐/mesoporous structure allows repetitive adsorption/desorption of small molecule carboxylic acids leading to highly selective sensing of formic acid over acetic acid. Fullerene‐based fullerphene nanosheet is an excellent functional material for sensing and other advanced applications.