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Construction of Carbon Dots Coated Magnetic Hollow Silica Spheres
Yue Zhao1, Shizhao Kang1, Pingping Yao2
1School of Chemical and Environmental Engineering, Shanghai Institute of Technology, 100 Haiquan Road, Shanghai 201418, China.
Abstract:
Magnetic hollow silica spheres (MHSS) with uniform cavity size and shell thickness were prepared using functionalized SiO₂ spheres as templates, on which the magnetic particles were uniformly deposited on their surface. The obtained MHSS exhibited a super-paramagnetic behavior at room temperature. Due to large hollow cavity space and super-paramagnetic characteristics, the MHSS were coated with carbon dots with assistance of (3-Aminopropyl) trimethoxysilane (APS). Thus, the preparedMHSS were mixed with citric acid and APS, followed by hydrothermal reaction at 180 °C, to generate carbon quantum dots coated MHSS (MHSS@CDs). Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder scattering (XRD), X-ray energy dispersive spectral analysis (EDS), Raman spectra and laser scattering particle analyzer were applied to characterize the MHSS and MHSS@CDs.
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