Zhiani Rahele, Es-Haghi Ali, Sadeghzadeh Seyed Mohsen, Shamsa Farzaneh
New Materials Technology and Processing Research Center, Department of Chemistry, Neyshabur Branch, Islamic Azad University Neyshabur Iran.
Young Researchers and Elite Club, Neyshabur Branch, Islamic Azad University Neyshabur Iran
RSC Adv. 2018 Dec 6;8(71):40934-40940. doi: 10.1039/c8ra06910g. eCollection 2018 Dec 4.
Photocatalytic selective oxidation has attracted considerable attention as an environmentally friendly strategy for organic transformations. Some methods have been reported for the photocatalytic oxidation of sulfides into sulfoxides in recent years. However, the practical application of these processes is undermined by several challenges, such as low selectivity, sluggish reaction rates, requirement of UV-light irradiation, use of additives, and instability of the photocatalyst. Pure monoclinic lead chromate nanoparticles were prepared a new simple way as Pb and Cr sources. PbCrO NPs were synthesized a green method in the presence of gum of ferula assa-foetida from Pb(NO) and CrCl as lead and chromium resources, respectively. The structural analysis of the samples confirmed the formation of PbCrO nanostructures in the range of 30 ± 5 nm. The PbCrO nanocatalyst was thoroughly characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDX) study. Considering the large ionic internal character and high mechanical and thermal stability as well as long-term colloidal stability, this system can be considered as a perfect nanocatalyst by using the host-guest approach. A green and ecofriendly method for oxidation of sulfides to sulfones in the presence of O as an oxidant was examined for the synthesised PbCrO NPs. The easy and applied reusability of the catalyst was observed after the completion of the reaction under visible-light irradiation.
光催化选择性氧化作为一种环境友好的有机转化策略已引起广泛关注。近年来，已有一些将硫化物光催化氧化为亚砜的方法被报道。然而，这些方法的实际应用受到了一些挑战的影响，如选择性低、反应速率缓慢、需要紫外光照射、使用添加剂以及光催化剂的不稳定性等。采用一种新的简单方法，以铅和铬源制备了纯单斜晶系铬酸铅纳米颗粒。以Pb(NO)和CrCl分别作为铅源和铬源，在阿魏胶存在下通过绿色方法合成了PbCrO NPs。样品的结构分析证实形成了粒径在30±5 nm范围内的PbCrO纳米结构。通过粉末X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和能量色散X射线光谱(EDX)研究对PbCrO纳米催化剂进行了全面表征。考虑到其较大的离子内禀特性、高机械稳定性和热稳定性以及长期的胶体稳定性，该体系可通过主客体方法被视为一种理想的纳米催化剂。考察了在合成的PbCrO NPs存在下，以O作为氧化剂将硫化物氧化为砜的绿色环保方法。在可见光照射下反应完成后，观察到该催化剂具有易于应用的可重复使用性。
