Soft-chemistry synthesis, solubility and interlayer spacing of carbon nano-onions

Abstract

We present a critical review of CNOs regarding the structure and synthesis process, elaborating the recent reports on soft-chemistry methods under mild conditions. In particular, solubility and interlayer spacing are discussed.

Fabrication of ultra-bright carbon nano-onions via a one-step microwave pyrolysis of fish scale waste in seconds

“…22,23 Pentagonal and hexagonal molecules have also been observed to play an important role in the assembly of fine and defect-free fullerene structures. 15 In addition, the phenyl radical was identified based on the MS spectra, as demonstrated by Fig. S1.…”

“…[8][9][10][11][12][13] Through post surface engineering afforded by covalent and non-covalent functionalization, water-soluble CNOs have been successfully applied in biotechnology, such as in in vitro, in vivo, and ex vivo bio-imaging and sensing, and in drug delivery. [14][15][16] Pech et al successfully fabricated micrometre-sized supercapacitors by utilizing onion-like carbon and attained a superior capacitance and volumetric energy that were significantly higher than those of conventional electrolytic capacitors. 11 Mohapatra et al developed dye-sensitized solar cells with a significant solar energy conversion efficiency by taking advantage of the excellent optical transparency and high electrical conductivity of CNO as an electrode.…”

Bioanalytical Applications of Graphene Quantum Dots for Circulating Cell-Free Nucleic Acids: A Review

“…This is an electrical breakdown of a gas that has developed an in-progress plasma discharge. It is the most suitable procedure for producing thermal plasma characterized by high-energy substances and the local thermal equilibrium state. − Although this approach for synthesizing GQDs looks to be a simple conventional method, it is challenging to achieve a high yield and requires careful control of experimental conditions. In a study, a water arc discharge technique with a controlled degree of oxidation is used to manufacture blue-emitting GQDs with tunable PL emission …”

Carbon Nano-onions: Potassium Intercalation and Reductive Covalent Functionalization

“…5 These multishell fullerenes have received considerable attention during the past decade due to their outstanding properties such as a large surface area to volume ratio, low densities, and a graphitic multilayer morphology, which makes them excellent candidates for diverse applications, such as energy conversion and storage, 6 supercapacitors, 7 solid lubricants, 8,9 and cellular imaging and theranostics, 10,11 among others. 4,12−15 CNOs can be synthesized through several methods, such as ball milling, 16 ion implantation, 17 arc discharge, 18 plasma treatment, 19 chemical vapor deposition, 20 laser ablation, 21 electron irradiation, 22 thermal decomposition of layered nanoreactors, 23,24 soft-chemistry methods, 25 and thermal annealing of detonation nanodiamonds (d-NDs) under either vacuum 26 or inert atmosphere. 27,28 The most common method for the synthesis of CNOs is based on the thermal annealing of d-NDs of about 5 nm diameter under a He atmosphere at temperatures between 1500 and 1800 °C.…”

“…CNOs can be synthesized through several methods, such as ball milling, ion implantation, arc discharge, plasma treatment, chemical vapor deposition, laser ablation, electron irradiation, thermal decomposition of layered nanoreactors, , soft-chemistry methods, and thermal annealing of detonation nanodiamonds (d-NDs) under either vacuum or inert atmosphere. , The most common method for the synthesis of CNOs is based on the thermal annealing of d-NDs of about 5 nm diameter under a He atmosphere at temperatures between 1500 and 1800 °C . Moreover, this method is highly reproducible and CNOs are obtained in quantitative yields, thus allowing a great potential for industrial applications.…”