The graphene based materials in water pollutant treatment have recently gained significant attention due to their high surface area, high mechanical strength and tuneable surface chemistry. However, the relatively high cost, poor hydrophobicity, low adsorption capacity, and recyclability limit their practical application. Here in, driven by need, we report a simple approach for the synthesis of graphene quantum dots (GQDs) via pyrolysis, preferred because of high controllability and fewer defects over chemical exfoliation methods. The synthesized GQDs are further embedded on bacterial cellulose nanopaper (BCN) and characterized using spectroscopy and microscopy techniques. Furthermore, the well-ordered multi-layered GQD embedded BCN based filtration assembly is designed and developed for treatment of water pollutants and industrial dye wastewater. The multi-layered GQD embedded BCN based filtration assembly is validated by purifying industrial dye and heavy metal (Hg²⁺, Pb²⁺) with removal efficiency of 99.6% and 97%, respectively. Our multi-layered filtration assembly demonstrated significant membrane regeneration capacity until six cycles. The isotherm model also showed an appropriate fit exhibiting good adsorption behaviour. Our multi-layered filtration assembly can be established as a promising filtration assembly for inexpensive, efficient and low energy applications in wastewater treatment.

Graphic abstract

中文翻译：

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基于GQD嵌入细菌纤维素纳米纸的多层过滤膜组件用于去除废水中的工业染料和重金属

由于其高表面积、高机械强度和可调节的表面化学性质，水污染物处理中的石墨烯基材料最近受到了极大的关注。然而，相对较高的成本、疏水性差、吸附能力低和可回收性限制了它们的实际应用。在此，受需求驱动，我们报告了一种通过热解合成石墨烯量子点 (GQD) 的简单方法，由于与化学剥离方法相比具有高可控性和更少缺陷，因此是首选方法。合成的 GQD 进一步嵌入细菌纤维素纳米纸 (BCN) 上，并使用光谱学和显微镜技术进行表征。此外，设计和开发了有序的多层 GQD 嵌入式 BCN 过滤组件，用于处理水污染物和工业染料废水。²⁺ , Pb ²⁺ ) 的去除效率分别为 99.6% 和 97%。我们的多层过滤组件在六个循环之前表现出显着的膜再生能力。等温线模型也显示出合适的拟合，表现出良好的吸附行为。我们的多层过滤组件可以作为一种有前途的过滤组件，用于废水处理中的廉价、高效和低能耗应用。

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