Conversion of Nanomaterial Waste Soot to Recycled Sc\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e3\u3c/sub\u3e Feedstock for the Synthesis of Metallic Nitride Fullerenes

Herein, we address a need in the industrial and academic communities to reduce costs and environmental impact associated with the synthesis of select carbonaceous nanomaterials. In this effort, we have developed a method to recover Sc2O3 from carbonaceous waste soot , thereby alleviating the problem of waste disposal of fullerene depleted soot and tremendously reducing the costs and environmental impact of our synthetic process. The recovery process is based on the thermal oxidation and removal of carbon from waste soot as gaseous byproducts (e.g., CO2) to yield a recycled, reusable feedstock. The economic impact is measured in the cost savings of solid waste disposal fees and expensive reagents, such as scandium and some rare-earth metal oxides. Our recovery method is scalable and simple in design. Waste soot at different stages of thermal oxidation is characterized by thermogravimetric analysis (TGA) to determine optimal temperature and soak parameters. Corresponding X-ray photoelectron spectroscopy (XPS) analysis of these samples indicates a comparable chemical composition Of SC2O3 for recycled samples to virgin Sc2O3 controls. Recovered SC2O3 material was used in our electric-arc reactor and resulted in statistically comparable fullerene product distributions

Effect of Copper Metal on the Yield of Sc\u3csub\u3e3\u3c/sub\u3eN@C\u3csub\u3e80\u3c/sub\u3e Metallofullerenes

The yield of Sc3N@C80 metallofullerene and fullerene extract is dramatically increased via filling cored graphite rods with copper and Sc2O3 only; when compared to 100% Sc2O3 packed rods, improvements of factors of ~3 and ~5 have been achieved for Sc3N@C80 and fullerene extract produced, respectively, with the weight percent of Cu added to the rod affecting the type and amount of fullerene produced

Chemically Adjusting Plasma Temperature, Energy, and Reactivity (CAPTEAR) Method Using NOx and Combustion for Selective Synthesis of SC3N@C-80 Metallic Nitride Fullerenes

Goals are (1) to selectively synthesize metallic nitride fullerenes (MNFs) in lieu of empty-cage fullerenes (e.g., C-60, C-70) without compromising MNF yield and (2) to test our hypothesis that MNFs possess a different set of optimal formation parameters than empty-cage fullerenes. In this work, we introduce a novel approach for the selective synthesis of metallic nitride fullerenes. This new method is Chemically Adjusting Plasma Temperature, Energy, and Reactivity (CAPTEAR). The CAPTEAR approach with copper nitrate hydrate uses NOx vapor from NOx generating solid reagents, air, and combustion to tune the temperature, energy, and reactivity of the plasma environment. The extent of temperature, energy, and reactive environment is stoichiometrically varied until optimal conditions for selective MNF synthesis are achieved. Analysis of soot extracts indicate that percentages of C-60 and Sc3N@C-80 are inversely related, whereas the percentages of C-70 and higher empty-cage C-2n fullerenes are largely unaffected. Hence, there may be a competitive link in the formation and mechanism of C60 and Sc3N@C-80. Using this CAPTEAR method, purified MNFs (96% SC3N@C-80, 12 mg) have been obtained in soot extracts without a significant penalty in milligram yield when compared to control soot extracts (4% Sc3N@C-80, 13 Mg of Sc3N@C-80). The CAPTEAR process with Cu(NO3)(2).2.5H(2)O uses an exothermic nitrate moiety to suppress empty-cage fullerene formation, whereas Cu functions as a catalyst additive to offset the reactive plasma environment and boost the SC3N@C-80 MNF production