Maleki Ali, Hajizadeh Zoleikha, Salehi Peyman
Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran.
Department of Phytochemistry, Medicinal Plants and Drugs Research Institute, Shahid Beheshti University, Evin, Tehran, Iran.
Sci Rep. 2019 Apr 3;9(1):5552. doi: 10.1038/s41598-019-42126-9.
In this study, mesoporous halloysite nanotubes (HNTs) were modified by CuFeO nanoparticles for the first time. The morphology, porosity and chemistry of the CuFeO@HNTs nanocomposite were fully characterized by Fourier transform infrared (FT-IR) spectroscopy, field-emission scanning electron microscopy (FE-SEM) image, transmission electron microscope (TEM) images, energy-dispersive X-ray (EDX), X-ray diffraction (XRD) pattern, Brunauer-Emmett-Teller (BET) adsorption-desorption isotherm, thermogravimetric (TG) and vibrating sample magnetometer (VSM) curve analyses. The results confirmed that CuFeO with tetragonal structure, uniform distribution, and less agglomeration was located at HNTs. CuFeO@HNTs nanocomposite special features were high thermal stability, crystalline structure, and respectable magnetic property. SEM and TEM results showed the nanotube structure and confirmed the stability of basic tube in the synthetic process. Also, inner diameters of tubes were increased in calcination temperature at 500 °C. A good magnetic property of CuFeO@HNTs led to use it as a heterogeneous catalyst in the synthesis of pyrazolopyridine derivatives. High efficiency, green media, mild reaction conditions and easily recovery of the nanocatalyst are some advantages of this protocol.
在本研究中，首次用铜铁氧体纳米颗粒对介孔埃洛石纳米管（HNTs）进行了改性。通过傅里叶变换红外（FT-IR）光谱、场发射扫描电子显微镜（FE-SEM）图像、透射电子显微镜（TEM）图像、能量色散X射线（EDX）、X射线衍射（XRD）图谱、布鲁诺尔-埃米特-泰勒（BET）吸附-脱附等温线、热重（TG）和振动样品磁强计（VSM）曲线分析，对CuFeO@HNTs纳米复合材料的形态、孔隙率和化学性质进行了全面表征。结果证实，具有四方结构、分布均匀且团聚较少的铜铁氧体位于HNTs上。CuFeO@HNTs纳米复合材料的特点是具有高热稳定性、晶体结构和可观的磁性。扫描电子显微镜（SEM）和透射电子显微镜（TEM）结果显示了纳米管结构，并证实了合成过程中基本管的稳定性。此外，在500 °C的煅烧温度下，管的内径增大。CuFeO@HNTs良好的磁性使其可作为合成吡唑并吡啶衍生物的多相催化剂。该方法的优点包括高效率、绿色介质、温和的反应条件以及纳米催化剂易于回收。
