Green Electronics NanoMaterials Group (GEMs), School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Seri Ampangan, Nibong Tebal, Pulau Pinang, Malaysia.
Sensor and Environmental Research Group (SERG), Department of Applied Sciences, Technology University MARA, Cawangan Pulau Pinang, Kampus Permatang Pauh, 13500, Permatang Pauh, Pulau Pinang, Malaysia.
Environ Sci Pollut Res Int. 2019 Apr;26(11):11482-11495. doi: 10.1007/s11356-019-04583-7. Epub 2019 Feb 26.
Silver nanoparticles (AgNPs) were prepared by reacting Kyllinga brevifolia extract (KBE) with AgNO aqueous solution at room temperature (22 ± 3 °C). The phytochemical constituents in KBE responsible for the reduction process were identified as carbohydrate, protein, and plant sterols (stigmasterol and campesterol). KBE was also found to function as a capping agent for stabilization of AgNPs. The AgNPs were stable at room temperature and had a quasi-spherical shape with an average particle size 22.3 nm. The use of KBE offers not only eco-friendly and non-pathogenic path for AgNPs formation, it also induced rapid formation of the AgNPs. Methylene blue (MB) removal was then done on the AgNPs in the presence of either KBE or NaBH. Ninety-three percent removal of MB was achieved with a rate of reaction 0.2663 min in the solution with KBE+AgNPs (pH 2). However, in NaBH+AgNPs system, 100% MB removal was achieved at pH 8-10. The reaction rate was 2.5715 min indicating a fast removal rate of MB dye. The process of reduction occurs via electron relay effect whereas in KBE+AgNPs system, sedimentation occurred along with the reduction process. Nevertheless, the use of KBE+AgNPs system is preferred as the reducing agent is more benign to the environment.
银纳米粒子（AgNPs）是通过在室温（22±3°C）下用 Kyllinga brevifolia 提取物（KBE）与 AgNO3 水溶液反应制备的。KBE 中负责还原过程的植物化学成分被鉴定为碳水化合物、蛋白质和植物甾醇（豆甾醇和菜油甾醇）。KBE 还被发现作为 AgNPs 稳定的稳定剂。AgNPs 在室温下稳定，具有准球形形状，平均粒径为 22.3nm。KBE 的使用不仅为 AgNPs 的形成提供了环保且非致病的途径，而且还诱导了 AgNPs 的快速形成。然后在存在 KBE 或 NaBH 的情况下，在 AgNPs 上进行亚甲蓝（MB）的去除。在 KBE+AgNPs（pH 2）溶液中，AgNPs 的反应速率为 0.2663 min，实现了 93%的 MB 去除率。然而，在 NaBH+AgNPs 体系中，在 pH 8-10 时实现了 100%的 MB 去除率。反应速率为 2.5715 min，表明 MB 染料的去除速率很快。还原过程通过电子传递效应发生，而在 KBE+AgNPs 体系中，还原过程伴随着沉淀发生。然而，由于还原剂对环境更友好，因此优选使用 KBE+AgNPs 体系。
