Synthesis of Graphitic Carbon Nanostructures from Sawdust and Their Application as Electrocatalyst Supports

Abstract

We present a novel and facile synthetic method for fabricating graphitic carbon nanostructures (GCNs) from sawdust. This method is based on the use of catalysts (Fe or Ni) that allows the direct conversion of sawdust into highly graphitized carbon material. The following procedure was used to obtain these graphitic nanoparticles: a) impregnation of the sawdust particles with iron or nickel salts, b) carbonization of the impregnated material at a temperature of 900 or 1000ºC, c) selective removal of the non-graphitized carbon (amorphous carbon) by an oxidant (KMnO 4 ). The resulting carbon is made up of nanosized graphitic structures (i.e. nanocapsules, nanocoils, nanoribbons), which have a high crystallinity, as evidenced by TEM/SAED, XRD and Raman analysis. These GCNs were used as supports for platinum nanoparticles. Such prepared electrocatalysts show an electrocatalytical surface area close to 90 m 2 .g -1 Pt and they present very promising results for methanol electrooxidation.

Direct synthesis of graphitic carbon nanostructures from saccharides and their use as electrocatalytic supports

“…those reported for electrocatalysts supported on other forms of graphitic carbon, such as mesocarbon microbeads [22], onion-like fullerenes [23], single-wall carbon nanotubes [24] or multiwalled carbon nanotubes [25]. We recently achieved similar ESA values for catalysts made up of Pt nanoparticles deposited on GCNs obtained from pine sawdust [10] and Fe(II) and Co(II) gluconates [11]. V for Pt/Vulcan is attributed to methanol electrooxidation.…”

“…Recently we reported the preparation of GCNs by using a cost-effective and widely available lignocellulosic material (sawdust) as precursor [10]. Likewise, we analyzed the use of commercially available iron or cobalt organic salts (i. e. Fe (II) gluconate and Co (II) gluconate) as precursors.…”

“…Based on these hypotheses, this work explores the use of three representative saccharides (glucose, sucrose and starch) as precursors for the synthesis of carbon nanostructures with a high crystallinity. The synthesis method employed to fabricate these nanostructures is similar to that described in our previous paper [10]. It consists in the thermal treatment, at a moderate temperatures (900-1000ºC), of the saccharides impregnated with metallic salts of Fe and Ni.…”

N-doped microporous carbon microspheres for high volumetric performance supercapacitors

“…This peak is superimposed on a broad band corresponding to amorphous carbon and it reveals the presence of a small fraction of graphitic carbon embedded inside an amorphous matrix. It results from the conversion of a small amount of amorphous carbon into more ordered carbon by the catalytic action of iron particles embedded inside the carbon matrix [39][40][41][42][43]. In the case of the sample carbonized at 600 ºC, only amorphous carbon was obtained.…”

Synthesis of graphitic mesoporous carbons with different surface areas and their use in direct methanol fuel cells

“…1. For a carbon material, the closer the interlayer spacing (d 002 ) is to that of graphite (0.3354 nm) [28], the more graphitic character is. As listed in Table 1, the interlayer spacing (d 002 ) for GMC-1 and GMC-2 is 0.341 and 0.336 nm, respectively.…”