研究目的
To develop a simple, fast one-step hydrothermal method for synthesizing ultrasmall and stable magnetite nanoparticles coated with a single carbon layer (Fe3O4@1C NPs) and evaluate their superparamagnetic behavior, long-term stability, and application in sensitive surface-enhanced Raman scattering (SERS) detection of molecules like Rhodamine B.
研究成果
The study successfully synthesized ultrasmall and stable Fe3O4@1C NPs via a facile hydrothermal method, demonstrating superparamagnetic behavior, excellent long-term stability against oxidation, and high SERS sensitivity for RdB detection. The carbon layer effectively protects the Fe3O4 core, making the NPs suitable for recyclable use in molecular sensing and other applications like biomedicine and magnetic separation.
研究不足
The synthesis temperature is limited to 200°C, which may restrict control over carbon layer thickness and particle size. The SERS application was only tested with specific dyes (RdB and MB), and further optimization for other molecules or biomedical applications is needed. The long-term stability was evaluated for 2 months; longer periods or harsher conditions were not tested.
1：Experimental Design and Method Selection:
The experiment used a one-pot hydrothermal method at 200°C for 12 hours to synthesize Fe3O4@1C NPs, involving dehydration and hydrothermal reactions. The design rationale was to achieve direct synthesis with ease of separation and purification.
2：Sample Selection and Data Sources:
Samples included Fe3O4@1C NPs synthesized from a mixture of polyvinyl alcohol (PVA), iron(III) nitrate enneahydrate (Fe(NO3)3·9H2O), and ethylene glycol (EG). Data sources were the synthesized nanoparticles and their characterization.
3：List of Experimental Equipment and Materials:
Equipment included a Teflon-lined stainless-steel autoclave, Rigaku D/max 2500v/pc XRD, FEI Tecnai G2 F20 TEM, EDXA, INC. EDS, Renishaw inVia Reflex confocal Raman microscope, and Squid-VSM Magnetic Measuring System. Materials included PVA, Fe(NO3)3·9H2O, EG, deionized water, absolute ethanol, and Rhodamine B.
4：Experimental Procedures and Operational Workflow:
Dissolved PVA in hot water and Fe(NO3)3·9H2O in deionized water, mixed them, added EG, transferred to autoclave, heated at 200°C for 12 h, cooled naturally, separated products magnetically, rinsed with ethanol and water, and used for SERS with RdB.
5：Data Analysis Methods:
XRD for phase structure, TEM for morphology, EDS for composition, Raman spectroscopy for carbon layer and SERS, and SQUID-VSM for magnetic properties. Data analyzed using Scherrer equation for particle size and intensity ratios in Raman spectra.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
