Department of Chemistry, Environmental Science Program, Faculty of Engineering and Technology (ITER), Siksha'O'Anusandhan (Deemed to be University), Bhubaneswar, 751030, Odisha, India.
Department of Civil Engineering, National Institute of Technology, Meghalaya, India.
J Environ Manage. 2022 Jan 15;302(Pt A):114022. doi: 10.1016/j.jenvman.2021.114022. Epub 2021 Nov 1.
In the present study, an attempt has been made to design a solar light driven N-rGO-ZnO- CoPc(COOH) nanocomposite for the degradation of cyanide. The morphological and structural characterization of the synthesized nanocomposite was performed by XRD, FT-IR, XPS, UV-vis DRS, FESEM, TEM, EDS, PL spectra and BET surface area. The results revealed that almost 91% degradation and 86% toxicity removal occurred at 25 mgL of initial cyanide concentration by the N-rGO-ZnO-CoPc(COOH) nanocomposite under illumination of solar light within 120 min. Analysis of free radicals reveals that the generation of OH radicals was the predominant species in the photocatalytic degradation process. The cyanide degradation follows pseudo-first order kinetics. The estimated apparent rate constant (K) of the above nanocomposite was 3 times higher than that of the ZnO photocatalyst alone together with a very good recycle activities. This might be due to the application of metallpthalocyanine photosensitizer CoPc(COOH) which enhances the rate of visible light absorption efficiency and activates the higher band gap ZnO photocatalyst under visible light. In addition, the presence of residual oxygen in N-rGO also promotes nucleation and anchor sites for interfacial contact between ZnO and N-rGO for effective charge transfer. Further, the N-rGO-ZnO-CoPc(COOH) photocatalytic system showed significant antibacterial activities against mixed culture systems. Therefore, the N-rGO-ZnO-CoPc(COOH) nanocomposite may be an alternative solar light driven photocatalyst system for the removal of cyanide from the wastewater along with its strong disinfectant activities.
在本研究中，尝试设计了一种太阳能驱动的 N-rGO-ZnO-CoPc(COOH)纳米复合材料，用于降解氰化物。通过 XRD、FT-IR、XPS、UV-vis DRS、FESEM、TEM、EDS、PL 光谱和 BET 表面积对合成的纳米复合材料进行了形态和结构表征。结果表明，在太阳能照射下，初始氰化物浓度为 25mgL 时，N-rGO-ZnO-CoPc(COOH)纳米复合材料在 120min 内几乎降解了 91%，去除了 86%的毒性。自由基分析表明，OH 自由基的生成是光催化降解过程中的主要物种。氰化物降解遵循准一级动力学。上述纳米复合材料的估计表观速率常数 (K) 比单独的 ZnO 光催化剂高 3 倍，且具有非常好的循环活性。这可能是由于应用了金属酞菁敏化剂 CoPc(COOH)，它提高了可见光吸收效率的速率，并在可见光下激活了更高带隙的 ZnO 光催化剂。此外，N-rGO 中残留的氧也促进了 ZnO 和 N-rGO 之间界面接触的成核和锚定位点，以实现有效的电荷转移。此外，N-rGO-ZnO-CoPc(COOH)光催化体系对混合培养体系表现出显著的抗菌活性。因此，N-rGO-ZnO-CoPc(COOH)纳米复合材料可能是一种替代的太阳能驱动光催化剂体系，可用于从废水中去除氰化物，同时具有很强的消毒剂活性。
