Ionic liquids and cellulose: Innovative feedstock for synthesis of carbon nanostructured material

Carbon nanostructured materials (CNMs) have vast capability in the field of energy, for storage and conversion purposes. Consequently, extensive greener and environmentally benign synthesis techniques that employ natural and readily renewable, low-cost waste materials need to be established. Herein, cellulose is considered as an alternative precursor source for the synthesis of CNMs. In the past decade, ionic liquids (ILs) have exhibited a great potential in a diverse number of applications. However, insignificant attention has been paid to the structure of ILs in relation to their extended application as a media for the dissolution of cellulose to avail carbon for CNMs synthesis. As baseline, a number of ionic liquids were used as carbon sources for CNM production, and distinct differences were found, depending on the type of ionic liquid used and the temperature of synthesis. Furthermore. CNMs were fabricated using a combination of the ionic liquid, 1-butyl-3-methylimidazolium chloride, [C4MIM] Cl, and cellulose, in the presence of ferrocene as catalyst precursor, using the floating catalyst chemical vapour deposition technique. Typical spaghetti like, hollow tubular structures with bamboo compartments, resembling N-doped multiwalled tubular carbon nanomaterials were observed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) respectively. Thermal stability studies showed thermogram profiles with a stability of around 550 degrees C. The sample synthesised with cellulose was more stable than the sample synthesised from IL and ferrocene only. Characteristic D- and G-bands were observed around 1380 and 1560 cm(-1), respectively, for Raman spectroscopy. X-ray diffraction (XRD) showed characteristic tubular carbon nanomaterials and or graphitic/N-graphitic diffraction patterns.