In this work, the degradation of 4-nitrophenol (4-NP) was investigated by using plasmonic gold nanoparticles decorated magnetic-porous silica microspheres (AuNP@Mag–SiO₂) as catalyst in the presence of excess sodium borohydride (NaBH₄) in batch fashion. Magnetic silica microspheres (Mag–SiO₂), 6.20 µm in size synthesized with high surface area and good magnetic properties were functionalized with amine groups. Using these particles as support, immobilization of gold nanoparticles (AuNP) was performed. The morphological, chemical and magnetic properties of the catalyst were analyzed by Scanning electron microscopy (SEM), Surface area and pore size analyzer, X-ray diffraction spectroscopy (XRD), Vibrating sample magnetometer (VSM) and X-ray photoelectron spectroscopy (XPS). The plasmonic catalytic activities of AuNP@Mag–SiO₂ microparticles were investigated by the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) monitored by UV–Vis spectroscopy by changing the reaction parameters such as amount of catalyst, Au loading, initial 4-NP concentration, and reaction temperature. Reaction times ranging between 5 and 30 min were obtained in the quantitative reduction of 4-NP using gold nanoparticles decorated magnetic silica (AuNP@Mag–SiO₂) microspheres. The plasmonic catalyst was recovered efficiently by magnetic separation and highly stable without exhibiting no significant activity decrease with the repeated use.

中文翻译：

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基于单分散多孔二氧化硅微球的电磁等离子体催化剂快速还原4-硝基苯酚

在这项工作中，在过量的硼氢化钠（NaBH ₄）存在下，使用等离激元金纳米颗粒修饰的磁性多孔二氧化硅微球（AuNP @ Mag-SiO ₂）作为催化剂，研究了4-硝基苯酚（4-NP）的降解。批处理时尚。磁性二氧化硅微球（Mag–SiO ₂），用胺基官能化了6.20 µm的具有高表面积和良好磁性的合成材料。使用这些颗粒作为载体，进行了金纳米颗粒（AuNP）的固定。通过扫描电子显微镜（SEM），表面积和孔径分析仪，X射线衍射光谱仪（XRD），振动样品磁力计（VSM）和X射线光电子能谱仪（XPS）分析了催化剂的形态，化学和磁性）。AuNP @ Mag-SiO ₂的等离子体激元催化活性通过改变反应参数，例如催化剂的量，Au的加入量，初始的4-NP浓度，反应时间等，通过UV-Vis光谱法监测了4-硝基苯酚（4-NP）还原为4-氨基苯酚（4-AP）的过程。和反应温度。在使用金纳米颗粒修饰的磁性二氧化硅（AuNP @ Mag-SiO ₂）微球定量还原4-NP的过程中，反应时间介于5分钟和30分钟之间。通过磁分离有效地回收了等离子体激元催化剂，并且该等离子体催化剂高度稳定，而随着重复使用其活性没有显着降低。