Speaker
摘要
纳米零价铁（nZVI）的环境修复潜力通常受到颗粒团聚严重或稳定性差的阻碍。克服这些挑战的直接方法是将nZVI均匀、牢固地分散到二维材料等高比表面积基底上。在此我们报道了一种基于共晶熔盐（MS）一锅合成MXene-nZVI复合材料的新策略。批次吸附实验表明，纳米层状MXene和nZVI之间的有效协同作用在提高复合材料消除U(VI)的性能方面发挥了关键作用,且最大去除量达到1750 mg/g。进一步的环境应用评估表明，MS-MXene-nZVI在去除复杂酸性矿井排水中的U(VI)方面潜力巨大。先进光谱分析清楚地证明了反应过程中Fe0向结构型Fe2+的转化，并确定了U(VI)的去除机制主要是还原固定，伴随着表面化学吸附和水解沉淀。这项研究为通过熔盐法绿色、简便地制备MXene基nZVI复合材料及其在高效分离放射性核素和其他污染物方面的环境修复应用提供了新的见解。
Abstract
The environmental remediation potential of nanoscale zero-valent iron (nZVI) is generally hindered by severe particle agglomeration or poor stability. A straightforward approach to overcome these challenges is to uniformly and firmly disperse nZVI onto high surface area substrates such as two-dimensional materials. Herein, we propose a novel method for one-pot synthesis of MXene-nZVI composites based on the eutectic molten salt (MS) etching of MAX phase materials. Batch adsorption experiments showed that the effective synergy between nano-lamellar MXene and nZVI played a pivotal role in boosting U(VI) elimination performance of the composites, and the maximum removal capacity reached 1750 mg/g. Further environmental application assessment indicated an excellent potential of MS-MXene-nZVI for U(VI) sequestration from complex acid mine drainage. Advanced spectroscopic analyses provided clear evidence of the conversion of Fe0 to structural Fe2+ during the reaction and established that the removal mechanism of U(VI) was primarily reductive immobilization, concomitantly with surface chemisorption and hydrolysis precipitation. This study offers new insights into the green and facile preparation of MXene-based nZVI composites via MS strategy, as well as their environmental remediation application in the highly efficient separation of radionuclides and other contaminants.
| 关键词 | MXene、纳米零价铁、熔盐合成、铀、环境修复 |
|---|---|
| Keywords | MXene、nZVI、Molten salt synthesis、Uranium、Environmental remediation |
