Batsukh Ikhbayar, Khishigjargal Tegshjargal, Dembereldorj Uuriintuya, Sambuu Munkhtsetseg, Ganbold Erdene-Ochir, Norov Erdene
Department of Chemical and Biological Engineering, School of Engineering and Applied Sciences, National University of Mongolia.
Institute of Physics and Technology, Mongolian Academy of Sciences, Ulaanbaatar, 13330, Mongolia.
ChemistryOpen. 2024 Sep;13(9):e202300297. doi: 10.1002/open.202300297. Epub 2024 Apr 16.
We synthesized Au/FeO microparticles. Initially, citrate-capped FeO micro-sized particles were synthesized by the co-precipitation method with an excess amount of trisodium citrate. Gold ions were reduced on the surface of citrate-capped FeO and grew as gold sub-microparticles with an average diameter of 210 nm on the surface. The characteristic SPR peak of gold nanoparticles on the surface of FeO was detected at 584 nm, whereas the absorption in the near-infrared region was increased. SEM images has proved that the synthesized Au/FeO composite microparticles has an average diameter of 1.7 micrometers. The results of XRD patterns proved the existence of both crystal phases of FeO and Au particles. To investigate the catalytic activity, the reaction rate constant of reduction of 2,4-dinitrophenol (2,4-DNP) and degradation of Congo red (CR), and methylene blue (MB) with NaBH4 in the presence of Au/FeO catalyst was monitored by UV-Vis spectroscopy. The initial reaction rate constant calculated from the change in characteristic peak absorptions of 2,4-dinitrophenol was 3.97×10 s, while the reaction rate constants for the degradation of CR and MB were 9.72×10 s and 14.25×10 s respectively. After 5 cycles, Au/FeO microparticles preserved 99 % of the reaction rate constant, exhibiting considerable recycling efficiency in the reduction of nitro groups.
我们合成了金/氧化亚铁微粒。最初，通过共沉淀法使用过量的柠檬酸三钠合成了柠檬酸包覆的微米级氧化亚铁微粒。金离子在柠檬酸包覆的氧化亚铁表面被还原，并在其表面生长为平均直径为210纳米的金亚微粒。在584纳米处检测到氧化亚铁表面金纳米颗粒的特征表面等离子体共振峰，而近红外区域的吸收增加。扫描电子显微镜图像证明合成的金/氧化亚铁复合微粒的平均直径为1.7微米。X射线衍射图谱结果证明了氧化亚铁和金颗粒两种晶相的存在。为了研究催化活性，通过紫外可见光谱监测在金/氧化亚铁催化剂存在下用硼氢化钠还原2,4-二硝基苯酚（2,4-DNP）以及刚果红（CR）和亚甲基蓝（MB）降解的反应速率常数。根据2,4-二硝基苯酚特征峰吸收变化计算出的初始反应速率常数为3.97×10⁻³ s⁻¹，而CR和MB降解的反应速率常数分别为9.72×10⁻³ s⁻¹和14.25×10⁻³ s⁻¹。经过5个循环后，金/氧化亚铁微粒保留了99%的反应速率常数，在硝基还原中表现出相当高的循环效率。
