Mahajan Hansa, Arumugasamy Shiva Kumar, Panda Atanu, Sada Venkateswarlu, Yoon Minyoung, Yun Kyusik
Department of Nanochemistry, Gachon University, Seongnam 13120, Republic of Korea.
Department of Bionanotechnology, Gachon University, Seongnam 13120, Republic of Korea.
ACS Omega. 2020 Sep 16;5(38):24799-24810. doi: 10.1021/acsomega.0c03487. eCollection 2020 Sep 29.
To ensure environmental safety, the removal of organic pollutants has gained increasing attention globally. We have synthesized uniform Au nanorod (NR)-doped CuO core-shell nanocubes (CSNCs) via a seed-mediated route embedded on the surface of rGO sheets. The Au NRs@CuO/rGO nanocomposite was characterized using various techniques such as transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared (FT-IR) and Raman spectroscopies. The scanning TEM-energy-dispersive spectroscopy (STEM-EDS) elemental mapping of the AuNRs@CuO/rGO nanocomposite indicates that the Au NR (40 nm) is fully covered with the CuO particles (∼145 nm) as a shell. N gas sorption analysis shows that the specific surface area of the composite is 205.5 m/g with a mesoporous character. Moreover, incorporation of Au NRs@CuO CSNCs increases the nanogaps around the nanoparticles and suppresses the stacking/bundling of rGO, which significantly influences the pore size and increase the surface area. A batch adsorption experiment was carried out under various parameters, such as the effect of pH, contact time, temperature, initial dye concentration, and adsorbent dosage, for the removal of methylene blue (MB) in aqueous solution. The high surface area and mesoporosity can cause the adsorption capacity to reach equilibrium within 20 min with a 99.8% removal efficiency. Both kinetic and isotherm data were obtained and fitted very well with the pseudo-second-order kinetic and Langmuir isotherm model. The Langmuir isotherm revealed an excellent dye sorption capacity of 243.9 mg/g at 298 K. Moreover, after five adsorption cycles, the dye removal efficiency decreased from 99 to 86%. This novel route paves a new path for heterogeneous adsorbent synthesis, which is useful for catalysis and electrochemical applications.
为确保环境安全，有机污染物的去除在全球范围内受到越来越多的关注。我们通过种子介导的方法合成了均匀的金纳米棒（NR）掺杂的氧化铜核壳纳米立方体（CSNCs），并将其嵌入还原氧化石墨烯（rGO）片的表面。使用各种技术对金纳米棒@氧化铜/还原氧化石墨烯纳米复合材料进行了表征，如透射电子显微镜（TEM）、原子力显微镜（AFM）、X射线衍射（XRD）、X射线光电子能谱（XPS）以及傅里叶变换红外（FT-IR）光谱和拉曼光谱。金纳米棒@氧化铜/还原氧化石墨烯纳米复合材料的扫描透射电子显微镜-能量色散光谱（STEM-EDS）元素映射表明，金纳米棒（40纳米）被作为壳层的氧化铜颗粒（约145纳米）完全覆盖。氮气吸附分析表明，该复合材料的比表面积为205.5平方米/克，具有介孔特征。此外，金纳米棒@氧化铜核壳纳米立方体的掺入增加了纳米颗粒周围的纳米间隙，并抑制了还原氧化石墨烯的堆叠/聚集，这显著影响了孔径并增加了表面积。在各种参数下进行了批量吸附实验，如pH值、接触时间、温度、初始染料浓度和吸附剂用量对水溶液中甲基蓝（MB）去除的影响。高比表面积和介孔性可使吸附容量在20分钟内达到平衡，去除效率达99.8%。获得了动力学和等温线数据，并与伪二级动力学和朗缪尔等温线模型拟合得很好。朗缪尔等温线显示在298K时染料吸附容量极佳，为243.9毫克/克。此外，经过五次吸附循环后，染料去除效率从99%降至86%。这条新途径为非均相吸附剂的合成开辟了一条新道路，对催化和电化学应用很有用。
