title: Determination of silicon and aluminum in silicon carbide nanocrystals by high-resolution continuum source graphite furnace atomic absorption spectrometry.
abstract: The determination of Al contaminant and the main component Si in silicon carbide (SiC) nanocrystals with the size-distribution of 1-8nm dispersed in an aqueous solution was developed using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS-GFAAS). The vaporization/atomization processes were investigated in a transversally heated graphite atomizer by evaporating solution samples of Al and Si preserved in various media (HCl, HNO3). For Si, the best results were obtained by applying a mixture of 5µg Pd plus 5µg Mg, whereas for Al, 10µg Mg (each as nitrate solution) was dispensed with the samples, but the results obtained without modifier were found to be better. This way a maximum pyrolysis temperature of 1200°C for Si and 1300°C for Al could be used, and the optimum (compromise) atomization temperature was 2400°C for both analytes. The Si and Al contents of different sized SiC nanocrystals, dispersed in aqueous solutions, were determined against aqueous (external) calibration standards. The correlation coefficients (R values) of the calibrations were found to be 0.9963 for Si and 0.9991 for Al. The upper limit of the linear calibration range was 2mg/l Si and 0.25mg/l Al. The limit of detection was 3µg/l for Si and 0.5µg/l for Al. The characteristic mass (m0) was calculated to be 389pg Si and 6.4pg Al. The Si and Al content in the solution samples were found to be in the range of 1.0-1.7mg/l and 0.1-0.25mg/l, respectively.
authors.affiliation: Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary. Electronic address: dravecz.gabriella@wigner.mta.hu.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Dravecz
authors.affiliation: Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary.
authors.forename: László
authors.initials: L
authors.lastname: Bencs
authors.affiliation: Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary; Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Műegyetem rakpart 3, H-1111 Budapest, Hungary.
authors.forename: Dávid
authors.initials: D
authors.lastname: Beke
authors.affiliation: Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary; Department of Atomic Physics, Budapest University of Technology and Economics, Budafoki út 8, H-1111 Budapest, Hungary.
authors.forename: Adam
authors.initials: A
authors.lastname: Gali
mesh_terms: D000535:Aluminum / Q000032:analysis* / Q000737:chemistry; D017554:Carbon Compounds, Inorganic / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006358:Hot Temperature; D057230:Limit of Detection; D053758:Nanoparticles / Q000737:chemistry*; D012825:Silicon / Q000032:analysis* / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry*; D013054:Spectrophotometry, Atomic / Q000379:methods*
chemical_list: D017554:Carbon Compounds, Inorganic; D017655:Silicon Compounds; D006108:Graphite; D000535:Aluminum; C022088:silicon carbide; D012825:Silicon
keywords: Atomization mechanism; Chemical modification; Electrothermal atomic absorption spectrometry; Nanomaterials; Refractory elements