Modification of structure and conductivity of nanohorns by toluene addition in carbon arc

Effect of Toluene Addition in an Electric Arc on Morphology, Surface Modification, and Oxidation Behavior of Carbon Nanohorns and Their Sedimentation in Water

“…They are attached at defective sites, namely, caps or opened ends of nanohorns. The latter increases the SSA value in agreement with the literature [ 1 , 2 , 8 , 9 , 44 , 46 ]. The pyrolysis of toluene in carbon arc produces hydrocarbon species.…”

“…Taking into account that the samples CNH-2 and CNH-8 mainly contain associates of spherical aggregates, this suggests that inter-aggregate pores in associates are also unavailable for N 2 adsorption. Moreover, a lower ability to adsorb nitrogen molecules could be due to the decoration nanohorn surface with –CH x groups, as was shown previously [ 2 ]. The SSA increases with the treatment temperature for all samples.…”

“…The synthesized CNHs can be assigned to the “seed-like” type [ 37 ]. Spherical aggregates in the sample CNH-0 consist of individual nanohorns with a length of ~5 nm and a diameter of ~2 nm (for details, see [ 2 , 5 ]). The SEM image of the sample CNH-0 shows 30–50 nm large nanohorn aggregates ( Figure 2 a).…”

“…The synthesis was performed using a setup for arc evaporation of graphite described in detail elsewhere [ 2 , 5 , 20 , 33 , 34 ]. The arc reactor consisted of a 150 L water-cooled chamber with graphite electrodes placed in its center (a 6 cm diameter hollow cooled anode and a 1.4 cm × 1.4 cm × 20 cm evaporated cathode of ~70 g in weight).…”

“…During the synthesis, the CNHs are combined into spherical particles, which can form large van der Waals associates [ 1 , 2 , 3 , 4 , 5 ]. High pore volume [ 6 , 7 , 8 ] and specific surface area (SSA) [ 9 , 10 ] make CNHs very promising for nanofluids [ 11 , 12 ], catalysis [ 13 , 14 ], medicine [ 15 , 16 , 17 , 18 ], electrochemistry [ 9 , 19 ], electromagnetic [ 2 , 5 , 20 ] and sensing applications [ 6 , 21 , 22 ]. In this regard, the improvement of availability of their pores for guest species, the increase of the SSA value, and the enhancement of the stability of their suspensions become very important.…”