Department of Chemical Engineering, Universiti Teknologi PETRONAS, Seri Iskandar, Perak, 32610, Malaysia.
Department of Pharmacy, Faculty of Pharmacy and Sciences, UHAMKA, Jakarta, 13460, Indonesia.
Chemosphere. 2021 Aug;277:130300. doi: 10.1016/j.chemosphere.2021.130300. Epub 2021 Mar 18.
In this present study, the tungsten oxide/amino-functionalized sugarcane bagasse derived-carbon quantum dots (WO/N-CQDs) composite has successfully been prepared through a simple mixing process. The WO was synthesized through a precipitation method, and CQDs were amino-functionalized using ethylenedinitrilotetraacetic acid (EDTA) and ethylenediamine (EDA) through one-pot hydrothermal method. It is revealed that N-CQDs incorporation into WO alters the bandgap energy, crystallinity, surface area, and photoluminescence (PL) properties. The produced composites exhibit higher monoclinic WO crystallinity, larger surface area, lower bandgap energy and quenched photoluminescence intensity. The as-prepared WO/N-CQDs composites exhibit better adsorption and photocatalytic degradation performance of methylene blue (MB) than the pristine WO. It shows that the combination of N-CQDs and WO enhanced visible light absorption, by lowering the bandgap energy of WO from 2.175 to 1.495 eV. The best performance composite is WO/N-CQDs EDA 2.5% with an efficiency of 96.86%, removal rate constant of 0.02017/min, and chemical oxidation demand (COD) removal efficiency achieved 84.61%. Moreover, the WO/N-CQDs EDA 2.5% shows a significant photocatalytic activity even at higher MB initial concentration with 92.93% removal for 50 ppm MB. Subsequently, the composite also has good stability after a sequential 3-times cycle of degradation with 86.85% removal. The increasing photocatalytic performance is affected by the quenching effect of PL and lower bandgap energy. The lower intensity of the PL indicates the reduced charge carrier recombination resulting in increased photocatalytic activity. The combination of N-CQDs and WO resulted in improved photodegradation, which shows its significant potential to be utilized for wastewater treatment.
在本研究中，通过简单的混合过程成功制备了氧化钨/氨基功能化甘蔗渣衍生碳量子点（WO/N-CQDs）复合材料。WO 通过沉淀法合成，CQDs 通过一锅水热法用乙二胺四乙酸（EDTA）和乙二胺（EDA）进行氨基功能化。结果表明，N-CQDs 的掺入改变了 WO 的能带隙能、结晶度、比表面积和光致发光（PL）性质。所制备的复合材料表现出更高的 WO 单斜晶型结晶度、更大的比表面积、更低的能带隙能和猝灭的光致发光强度。与原始 WO 相比，所制备的 WO/N-CQDs 复合材料对亚甲基蓝（MB）具有更好的吸附和光催化降解性能。结果表明，N-CQDs 和 WO 的结合增强了可见光吸收，将 WO 的能带隙能从 2.175 降低到 1.495 eV。性能最佳的复合材料是 WO/N-CQDs EDA 2.5%，其效率为 96.86%，去除率常数为 0.02017/min，化学需氧量（COD）去除效率达到 84.61%。此外，WO/N-CQDs EDA 2.5% 在较高的 MB 初始浓度下也表现出显著的光催化活性，50 ppm MB 的去除率达到 92.93%。随后，该复合材料在 3 次降解循环后仍具有良好的稳定性，去除率为 86.85%。光催化性能的提高受 PL 的猝灭效应和较低的能带隙能的影响。PL 强度的降低表明减少了载流子复合，从而提高了光催化活性。N-CQDs 和 WO 的结合提高了光降解性能，这表明其在废水处理方面具有重要的应用潜力。
