Graphene-like nanostructures obtained from Biomass

Abstract

Two dimensional (2D) carbon nanomaterials such as few graphite layers or graphene are extensively studied due to their unique properties suitable to be exploiting in a wide range of technological applications. Recently, the growth of high quality graphene monolayers using insects and waste as carbon precursors was reported in the literature. This methodology opened a new way to convert the waste carbon into a high-value-added product. In the present work coconut coir dust, an agroindustrial biomass, was used as biotemplate for preparing carbonaceous materials. Carbon structures were synthesized through pyrolysis under nitrogen atmosphere (100mL/min) at 500, 1000, and 1500°C during 2 hours. Starting materials were coconut coir dust in natura and coconut coir dust hydrothermally treated. The samples were characterized by X-ray diffraction, Raman Spectroscopy, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Raman spectra showed the D band for all samples, related to the presence of defects in sp2 carbon structure and G band, indicative of graphite crystallites. It was also observed that the sample carbonized at 1500°C from coconut coir dust treated by hydrothermal method showed G’ band at 2685cm-1 associated with the stacking order along the c-axis. X-ray diffraction analysis showed a broad peak around 2θ= 22° related to the presence of amorphous carbon. By increasing the pyrolysis temperature changes in XRD diffractograms were observed and the sample which was pyrolysed at 1500°C from coconut coir dust hydrothermally treated showed peaks at 2θ= 26.5°, 43° e 45° assigned to (002), (100) (101) graphite plans, respectively. Scanning electron microscopy images showed the presence of overlapping sheets and plates. Transmission Electron Microscopy (TEM) images of coconut coir dust in natura unveiled the formation of amorphous sheet. Coconut coir dust in natura and treated by the hydrothermal method pyrolysed at 1500°C, lead to the formation of some graphitic domains and few graphene layers.

Synthesis and Characterization of Carbon Material Obtained from Coconut Coir Dust by Hydrothermal and Pyrolytic Processes

“…All hydrothermal products exhibit a similar morphology -a sheet-like structure -to CCD, owing to high lignin composition; lignin generally exhibits a more complex structure. Moreover, lignin acts as a hard bio-template while keeping cellulose contained inside (Barin et al, 2013).…”

“…Moreover, epitaxial growth requires an expensive silicon carbide (Muramatsu et al, 2014). The production of graphene-like material from coconut coir dust has been done, but it requires high temperatures of up to 1500 o C (Barin et al, 2013). The research described in this study aims to provide a scalable method for the production of carbon material containing graphene domains, by varying hydrothermal temperatures followed by pyrolysis.…”

General overview of graphene: Production, properties and application in polymer composites

“…One other method that has been reported for production of graphene is from biomass [61][62][63][64]. This is also an interesting method given the nature of biomass, i.e.…”

Green syntheses of graphene and its applications in internet of things (IoT)—a status review

“…Using cobalt salt, they have also created multilayer-graphene-encapsulated cobalt nanoparticles core-shell structure for energy applications [117]. Similarly, few-layer graphene-like nanostructures are created using coconut coir dust as the carbon source and pyrolyzed under nitrogen (100 ml min −1 ) at different temperatures (500 °C, 1000 °C, and 1500 °C) for 2 h [118]. Various other bio-mass and bio-mass wastes are also used to derive graphene and graphene-like nanostructures via N 2 /Ar-pyrolization, chemical vapor deposition (CVD), plasma treatments (or similar) processes, which include alginate, sugar-cane wastes, dead camphor leaves, oil palm fruit brunch/mill effluent/fibers/oil, wheat straw, chitosan, food wastes (cookies, chocolates etc), grass, dog feces, roaches (cockroach legs), mango peel, soybeans shell/oil, spruce bark, Populus wood, Macadamia nut shell, Bengal gram bean husk, paper wastes (news paper, paper cups etc), waste chicken fat, sucrose, gelatin, sticky rice, shrimp shell, Larch wood clips, Salvia splendens petals, clover precursor, cornstalk, coconut shell, cucumbers, silk cocoons, milk products (milk powder, condensed milk, processed/cream cheese, butter etc), honey, sugar bamboo, ginger root, raw cotton, pine nut shells, potatoes, bread, neem/mango/cauliflower leaves, spent tea, starch, etc [119][120][121][122][123][124][125][126].…”