Rossi Bruno L, Andrade Cláudia M B, Therézio Eralci M, Ramos Romildo J, Vasconcelos Leonardo G, Terezo Ailton J, De Siqueira Adriano B
Genmat/Rede MT-NanoAgro- Departamento de Química/ICET, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil.
Instituto de Física, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil.
Front Chem. 2022 Aug 11;10:858323. doi: 10.3389/fchem.2022.858323. eCollection 2022.
Sewage sludge, produced daily and inherent to urban development, presents problems of disposal that are still challenging today. Its disposal still offers palliative solutions, where the final destination is generally in landfills or, restrictively, to use in agriculture. The synthesis of carbon quantum dots (CQDs) from sewage sludge is a better alternative to use the stock of organic material present in the sludge. The present work aims to produce Carbon quantum dots (CQDs) using principles of green chemistry and to use an alternative raw material intrinsic stock of carbon present in sewage sludge, making its final disposal more sustainable. The material obtained has a core structure mainly composed of sp carbon and nitrogen. The surface functional groups containing sulfur, nitrogen, and oxygen of CQDs were investigated using FTIR and TG/DSC coupled FTIR techniques. The CQDs showed a luminescence decay time equivalent to fluorescent compounds and with satisfying quantum yield since no passive/oxidizing agent or material purification process was used. The photoluminescence spectroscopy analysis showed that the CDQs excitation λ was at 360 nm and caused a λ emission at 437 nm (CQDs) and 430 nm (CQDs). The CQDs obtained showed sizes of 9.69 ± 2.64 nm (CQDs) and 10.92 ± 2.69 nm (CQDs). experiments demonstrated the uptake of CQDs by the endothelial cell line EAhy 926 and their nontoxicity. However, the production of CQDs can be used for the sustainable disposal of sewage sludge.
城市发展中每天都会产生污水污泥，其处置问题至今仍具有挑战性。其处置方式仍多为治标之法，最终去向通常是填埋场，或者严格限制用于农业。利用污水污泥合成碳量子点（CQDs）是更好地利用污泥中有机物质存量的一种选择。本研究旨在运用绿色化学原理制备碳量子点（CQDs），并利用污水污泥中固有的碳这种替代原料，使其最终处置更具可持续性。所获得的材料具有主要由sp碳和氮组成的核心结构。采用傅里叶变换红外光谱（FTIR）以及热重/差示扫描量热联用傅里叶变换红外光谱（TG/DSC coupled FTIR）技术研究了碳量子点含硫、氮和氧的表面官能团。由于未使用钝化/氧化剂或材料纯化工艺，碳量子点显示出与荧光化合物相当的发光衰减时间以及令人满意的量子产率。光致发光光谱分析表明，碳量子点的激发波长为360 nm，发射波长为437 nm（CQDs）和430 nm（CQDs）。所获得的碳量子点尺寸为9.69±2.64 nm（CQDs）和10.92±2.69 nm（CQDs）。实验证明内皮细胞系EAhy 926能够摄取碳量子点且其无毒。然而，碳量子点的制备可用于污水污泥的可持续处置。
