Centre for Nanoscience and Nanotechnology, Jamia Millia Islamia, New Delhi, 110025, India.
Smart Materials Research and Device Technology (SMaRDT) Group, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK.
Environ Sci Pollut Res Int. 2023 Jan;30(2):4151-4165. doi: 10.1007/s11356-022-22487-x. Epub 2022 Aug 13.
COVID-19-led antibiotic waste generated from hospitals and health centres may cause serious health issues and significantly impact the environment. In the coming decades, antibiotic resistance will be one of the most significant threats to global human health. Photocatalytic water remediation is an effective and promising environmental solution that can be utilized to address this issue, to convert antibiotic waste into non-toxic products by utilizing renewable and abundant solar energy. In the present study, a novel nanocomposite of zeolitic imidazolate frameworks (ZIF-8) and molybdenum diselenide (MoSe) was efficiently synthesized by the solvothermal method for the complete degradation of the antibiotics and textile waste from water. The morphology, crystallinity and band gap of the samples were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and UV-visible spectroscopy. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) provide the binding information of the sample. The photocatalytic activity was tested for degradation of the antibiotics (tetracycline hydrochloride (TC) and metronidazole (MNZ)) used in COVID-19 treatment and textile dye (malachite green). Time-resolved photoluminescence spectroscopy confirmed the enhanced charge separation in the MoSe@ZIF-8 nanocomposite with an average lifetime of 4.72 ns as compared to pristine samples. The nanocomposite showed ~ 100% removal efficiency with rate constants of 63 × 10, 49 × 10 and 42 × 10 min for TC, MNZ and malachite green, respectively. The photocatalytic degradation of TC was carried out under different pH conditions (4, 7 and 9), and the degradation mechanism was explained on the basis of zeta potential measurements and active species trapping experiment. The by-products of the photocatalytic treatment of TC antibiotics were tested using liquid chromatography-mass spectroscopy (LC-MS), and they were found to be non-toxic for aquatic and human life. The regeneration property of the nanocomposite was confirmed by FESEM with regeneration efficiency of 88.7% in the 4th cycle. Thus, MoSe@ZIF-8-based photocatalysts have potential application in water remediation, especially in making the antibiotic waste less toxic.
COVID-19 引发的抗生素废物来自医院和医疗中心，可能会导致严重的健康问题，并对环境造成重大影响。在未来几十年，抗生素耐药性将成为对全球人类健康的最大威胁之一。光催化水修复是一种有效的、有前途的环境解决方案，可以利用可再生的丰富太阳能将抗生素废物转化为无毒产品。在本研究中，通过溶剂热法高效合成了沸石咪唑酯骨架（ZIF-8）和二硒化钼（MoSe）的新型纳米复合材料，用于完全降解水中的抗生素和纺织废物。通过场发射扫描电子显微镜（FESEM）、X 射线衍射（XRD）和紫外-可见光谱对样品的形貌、结晶度和带隙进行了表征。傅里叶变换红外光谱（FTIR）和 X 射线光电子能谱（XPS）提供了样品的结合信息。通过测试用于 COVID-19 治疗的抗生素（盐酸四环素（TC）和甲硝唑（MNZ））和纺织染料（孔雀石绿）的降解来测试光催化活性。时间分辨光致发光光谱证实，与原始样品相比，在 MoSe@ZIF-8 纳米复合材料中增强了电荷分离，平均寿命为 4.72 ns。该纳米复合材料的去除效率约为 100%，TC、MNZ 和孔雀石绿的速率常数分别为 63×10、49×10 和 42×10 min。在不同的 pH 条件（4、7 和 9）下进行 TC 的光催化降解，并根据动电位测量和活性物种捕获实验解释降解机制。使用液相色谱-质谱（LC-MS）测试了 TC 抗生素光催化处理的副产物，发现它们对水生和人类生命无毒。通过 FESEM 确认了纳米复合材料的再生性能，在第 4 个循环中再生效率为 88.7%。因此，基于 MoSe@ZIF-8 的光催化剂在水修复方面具有潜在的应用，特别是在使抗生素废物毒性降低方面。
