School of Chemistry and Biochemistry, Thapar Institute of Engineering & Technology, Patiala, 147004, India.
Center for Electrochemical Science & Materials, Department of Chemistry, K.L.E. Institute of Technology, Hubballi, 580027, Karnataka, India.
J Environ Manage. 2020 Nov 15;274:111208. doi: 10.1016/j.jenvman.2020.111208. Epub 2020 Aug 16.
Photodegradation of toxic pollutants is a promising approach to deal with wastewater management. In this regard, MoS/g-CN (MSC) derived composites with varying weight-ratios were prepared via fast (30 min) one step microwave-assisted method. The materials were characterized by XRD, XPS, EDS, FESEM and HRTEM to validate their flower-like and sheet-like morphologies. The PL and UV-vis DRS spectra exhibited low recombination-rate and band-gap (1.7 eV), which is appropriate for an effective visible-light degradation. Photocatalytic performance of the catalysts was analyzed by investigating the degradation of methylene blue (MB) as well as pesticide fipronil. Best results were obtained by 5:1 MSC (98.7% degradation efficacy; rate constant 0.0261 min) in 80 min under the sunlight. The effects of solution pH, catalyst-dose, scavengers and illumination-area were also explored. The catalyst was reusable as confirmed by degradation studies (~82% efficiency) even after 5-cycles. The photocatalytic treatment of real industrial-wastewater was also conducted. The TOC and COD analysis validated that the treatment by as-prepared catalyst is more proficient for effluent-treatment than the industrial physico-chemical treatments. Electrochemical degradation of MB was also investigated using the glassy carbon electrode modified with different MSC-ratios. The electrode modified with 5:1 MSC at pH 7 manifested the maximum peak current. The plausible mechanisms for photocatalytic and electrochemical degradations were proposed, which suggested the remarkable potential the prepared nanocomposites for wastewater treatment.
光降解有毒污染物是处理废水管理的一种很有前途的方法。在这方面，通过快速（30 分钟）一步微波辅助法制备了具有不同重量比的 MoS/g-CN（MSC）衍生复合材料。通过 XRD、XPS、EDS、FESEM 和 HRTEM 对材料进行了表征，以验证其花状和片状形貌。PL 和 UV-vis DRS 光谱显示出低复合率和带隙（1.7 eV），这适合有效利用可见光降解。通过研究亚甲基蓝（MB）和杀虫剂氟虫腈的降解来分析催化剂的光催化性能。在阳光下 80 分钟内，5:1 MSC（降解效率 98.7%；速率常数 0.0261 min）获得了最佳结果。还研究了溶液 pH 值、催化剂剂量、清除剂和光照面积的影响。通过降解研究（~82%的效率）证实了催化剂的可重复使用性，即使经过 5 次循环也是如此。还对实际工业废水进行了光催化处理。TOC 和 COD 分析验证了，与工业物理化学处理相比，用制备的催化剂进行处理对废水处理更有效。还使用不同 MSC 比修饰的玻璃碳电极研究了 MB 的电化学降解。在 pH 7 下，用 5:1 MSC 修饰的电极表现出最大的峰电流。提出了光催化和电化学降解的可能机制，这表明了所制备的纳米复合材料在废水处理方面具有显著的潜力。
