Green synthesis of graphene using leaf extracts as sustainable reducing and capping agents is a thrust area of research owing to its simplicity, eco-friendly nature and the ease of access to graphene. Moringa (Moringa oleifera Lam) plant is widely cultivated in India owing to its important medicinal and nutritional values. Inspired by these reports, herein we report a simple, green and economic synthesis of graphene, Moringa leaf extract employed reduced graphene oxide (MRGO) with excellent dye removal efficiencies. The MRGO is prepared by refluxing a mixture of aqueous dispersion of graphene oxide and Moringa leaf extract for 10 h. Further, we elucidated the role of synthesized MRGO in the removal of methylene blue (MB) and rhodamine B (RB) dyes through the sonochemical method. This as-synthesized material exhibited excellent dye removal efficiencies of about 93% and 87% against MB and RB dyes, respectively. Graphene with huge surface area expedited the better adsorption of dye molecules, thus, facilitated the better removal of the latter. Therefore, the superior dye removal efficiencies of MRGO were attributed to its adsorption capacity. This cost-effective synthetic approach of MRGO nanomaterial has a great potential for the innovative applications in water purification technology and find its place in further industrialization.

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中文翻译：

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具有成本效益的石墨烯生物合成方法，具有优异的声化学染料去除能力

使用叶提取物作为可持续的还原剂和加帽剂进行石墨烯的绿色合成，由于其简单，生态友好的性质以及获得石墨烯的便利性，是研究的重点领域。辣木（Moringa oleifera Lam）植物因其重要的药用和营养价值而在印度广泛种植。受这些报道的启发，本文报道了一种简单，绿色且经济的石墨烯合成方法，辣木叶提取物采用了还原性氧化石墨烯（MRGO），具有出色的染料去除效率。通过回流氧化石墨烯和辣木的水分散体的混合物来制备MRGO叶提取物10小时。此外，我们阐明了通过声化学方法合成的MRGO在去除亚甲基蓝（MB）和若丹明B（RB）染料中的作用。这种合成后的材料对MB和RB染料分别具有约93％和87％的优异的染料去除效率。具有大表面积的石墨烯促进了染料分子的更好吸附，因此促进了染料分子的更好去除。因此，MRGO的优异的染料去除效率归因于其吸附能力。这种具有成本效益的MRGO纳米材料合成方法在水净化技术的创新应用方面具有巨大潜力，并在进一步的工业化中占有一席之地。

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