Shukla Falguni, Kikani Twara, Khan Anisha, Thakore Sonal
Department of Chemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara 390002, India.
Department of Chemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara 390002, India; Institute of Interdisciplinary Studies, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara 390002, India.
Int J Biol Macromol. 2022 Jun 1;209(Pt A):1504-1515. doi: 10.1016/j.ijbiomac.2022.04.149. Epub 2022 Apr 23.
This study reports a sonochemical approach for the synthesis and catalytic performance of zerovalent iron nanoparticles (nZVI) capped with two cyclodextrin (CD) crosslinked polymers derived from Lactic acid and Citric acid (CDLA and CDCA respectively). The polymers and the catalysts were characterized by NMR, FTIR, HRTEM, DLS, Zeta potential, FESEM, EDAX, VSM, XRD, XPS, TGA analysis. The catalysts proved to be sustainable and recyclable for rapid sonochemical reduction of nitroaromatics under ambient conditions. The isolated yield of the derivatives was found to be greater than 90%. The results suggest excellent dispersibility, stability, high iron content and smaller size of CDLA polymer capped nZVI compared to CDCA capped nZVI, leading to two-fold higher catalytic activity. The effect of various crucial catalysis parameters was investigated and optimized. The scope of the reaction was extended to other nitroaromatics under the optimized conditions. Being magnetically separable, the cost effective and non-toxic catalysts exhibited high recycling efficiency (~13 cycles), high turnover number (TON) and turnover frequency (TOF). The recyclable catalysts could be low-cost and sustainable options for organic transformation in water via sonochemical approach in aqueous medium.
本研究报道了一种声化学方法，用于合成由乳酸和柠檬酸衍生的两种环糊精（CD）交联聚合物（分别为CDLA和CDCA）包覆的零价铁纳米颗粒（nZVI）及其催化性能。通过核磁共振（NMR）、傅里叶变换红外光谱（FTIR）、高分辨率透射电子显微镜（HRTEM）、动态光散射（DLS）、zeta电位、场发射扫描电子显微镜（FESEM）、能谱分析（EDAX）、振动样品磁强计（VSM）、X射线衍射（XRD）、X射线光电子能谱（XPS）、热重分析（TGA）对聚合物和催化剂进行了表征。结果表明，在环境条件下，该催化剂可实现可持续和可循环使用，用于快速声化学还原硝基芳烃。衍生物的分离产率大于90%。结果表明，与CDCA包覆的nZVI相比，CDLA聚合物包覆的nZVI具有优异的分散性、稳定性、高铁含量和更小的尺寸，催化活性提高了两倍。研究并优化了各种关键催化参数的影响。在优化条件下，反应范围扩展到其他硝基芳烃。由于具有磁分离性，这种经济高效且无毒的催化剂表现出高循环效率（约13次循环）、高周转数（TON）和周转频率（TOF）。这种可循环使用的催化剂可能是在水介质中通过声化学方法进行水中有机转化的低成本且可持续的选择。
