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Silicon carbide(SiC) quantum dots(QDs) in aqueous suspension were produced via corrosion in a mixture of chemical etchants(i.e.,HNO_3 and HF),ultrasonic dispersion and centrifugation.The microstructural evolution of rawβ-SiC particles during the etching process was examined.The porous structure of the β-SiC raw particles obtained due to the hydrofluoric-acid-induced dissociation of Si—O bonding and oxidation by nitric acid was investigated.The hollow and grid-like structures formed in the corrosion process were broken due to the cavitation and crushing of ultrasonic treatment,forming SiC-QDs.The homogeneous SiC-QDs in aqueous suspension were obtained in a centrifuge.Effect of preparation parameters on the spectral characteristics of the SiC-QDs was analyzed.The results show that the maximum photo-luminescence(PL) intensity of the SiC-QDs can be obtained at excitation wavelengths of 340 nm.The PL intensity and emission wavelength are affected by the volume ratio of the mixture of chemical etchants and the duration of ultrasonic treatment.Moreover,the color of the fluorescence is related to the size of the SiC-QDs.
Silicon carbide (SiC) quantum dots (QDs) in aqueous suspension were produced via corrosion in a mixture of chemical etchants (ie, HNO_3 and HF), ultrasonic dispersion and centrifugation. Microstructural evolution of raw β-SiC particles during the etching process. The porous structure of the β-SiC raw particles obtained due to the hydrofluoric-acid-induced dissociation of Si-O bonding and oxidation by nitric acid was investigated. Hollow and grid-like structures formed in the corrosion process were broken due to the cavitation and crushing of ultrasonic treatment, forming SiC-QDs.The homogeneous SiC-QDs in aqueous suspension were obtained in a centrifuge. Effect of preparation parameters on the spectral characteristics of the SiC-QDs was analyzed. results show that the maximum photo The luminescence (PL) intensity of the SiC-QDs can be obtained at the wavelength of 340 nm. The PL intensity and emission wavelength are affected by the volume ratio of the mixture of ch emical etchants and the duration of ultrasonic treatment. More over, the color of the fluorescence is related to the size of the SiC-QDs.