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We demonstrate a unique one-pot synthesis approach to obtain sulfonated carbon nanoplates having elongated hexagonal morphology (S-ECN). The S-ECN was synthesized by dehydration of recrystallized sucrose and sodium chloride mixed crystals with concentrated sulfuric acid under ambient conditions. No additional heat treatment or elaborate experimental setup was necessary to obtain graphitic carbon nanoplates. Scanning electron microscopy (SEM) studies showed that the presence of NaCl and recrystallization conditions played a crucial role in crystal habit modification of sucrose during recrystallization. Consequently, initial morphology of sucrose crystals was largely preserved in resultant carbon nanostructures. X-ray diffraction, Raman spectroscopy, and transmission electron microscopy studies showed that S-ECN was partially graphitic with wider interplanar spacing compared to standard graphite. The elemental analysis (CHNS) and Fourier transform infrared (FTIR) spectroscopic studies confirm the presence of sulfur in the form of −SO3H group. The catalytic performance of the S-ECN was studied for hydroxyalkylation–alkylation (HAA) reaction of 2-methylfuran with furfural to produce C15 oxygenated hydrocarbon. The S-ECN showed up to 90% conversion of 2-methylfuran. Additionally, an empirical kinetic model was developed to obtain rate constant of HAA reaction and to correlate 2-methylfuran conversion under various reaction conditions. The experimental results matched reasonably well with the calculated 2-methylfuran conversion.

We report a two-step process to synthesize nitrogen-doped graphene-like carbon nanosheets (N-CNS), using commercially available ethyl cyanoacrylate based super glue as a carbon precursor. In this process, super glue is polymerized in aqueous NaCl solution, followed by carbonization at 1000 °C. Scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) studies show that the resultant material consists of micron-sized carbon nanosheets with a wrinkled morphology. HRTEM, X-ray diffraction (XRD), XPS and Raman spectroscopic studies confirm the formation of nanocrystalline and graphitic, nitrogen-doped carbon nanosheets. A detailed FTIR analysis of the degradation products of the polymeric precursor (polyethyl cyanoacrylate) at various heat treatment temperatures under an inert atmosphere reveals that the polymer undergoes a cyclization process similar to polyacrylonitrile (PAN) during carbonization to yield the N-CNS. The N-CNS used as an anode for a lithium-ion battery shows stable reversible capacities of 480 mA h g-1 for 100 cycles, which indicates that N-CNS are promising materials for lithium-ion battery applications. In a broader perspective, a unique chemical transformation of polyethyl cyanoacrylate to graphitic carbon may be useful to design new nanostructured carbons for a plethora of applications.

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