Table 3.
Latest innovations regarding nano-enabled materials for soil remediation.
| Nanomaterials | Remarks | Ref. |
|---|---|---|
| CaAl-layered double hydroxide (CaAl-LDH) | The efficacy of CaAl-layered double hydroxide (CaAl-LDH) as an efficient stabilizer in cadmium-contaminated soil has been investigated. Due to its 96.9% immobilization efficiency for cadmium in contaminated soil, this material was recommended as a promising competitive candidate for facile remediation of Cd-contaminated soils. | [81] |
| Micro zerovalent iron (ZVI) and nano zerovalent iron (nZVI) | The capability of ZVI and nZVI to efficiently immobilize metals and metalloids, i.e., As, Cu, Cr, Zn, and Pb, were compared by analyzing two different contaminated soils. nZVI revealed the best performance for all the tested species. Analyses on the long-term stability of metal (loid) by thermal oxidation tests revealed good retention of As and Cu and significant desorption of Pb. For the long-term stability of metal (loid)s in soil, the exploitation of micro-Fe over nano-Fe has been recommended due to the slow oxidation of the former. | [82] |
| Low-cost Fe/Al-based materials | The use of three low-cost Fe/Al-based materials, including red soil (RS), sponge iron filters (SIF), and Al-based water treatment sludge (WTS), as amendments to remediate arsenic-contaminated soils under anoxic condition, was analyzed. SIF was revealed to be the more promising material in comparison with the other two to remediate the As-contaminated soil. | [83] |
| A thiol-modified rice straw biochar (RS) | A novel thiol-modified RS was synthesized by esterification with β-mercaptoethanol for the remediation of Cd2+ and Pb2+ contaminated soils. RS selectively adsorbed Cd2+ over Pb2+ and reduced Cd availability by up to 40% while enabling limited immobilization of Pb. RS revealed an effective amendment for remediation of soil pollution. | [84] |
| Nanoscale ferrous sulfide | The efficiency, stability, and feasibility of using sodium carboxymethyl cellulose-stabilized nanoscale ferrous sulfide (CMC-nFeS) for the immobilization of Cr (VI) in contaminated soil were demonstrated, along with the reaction mechanism between CMC-nFeS and Cr (VI) in a neutral environment. | [85] |
| Zeolite-supported nanoscale zero-valent iron (Z-NZVI) | This study provides detailed information on the encapsulation mechanisms of heavy metals/loids (Cd, Pd, and As) and the ecological risks of Z-NZVI in real farmland soils. The secondary mineralization of Z-NZVI bonded metal (loid)s, and improved soil quality afford its use for the long-term remediation of metals/loids contaminated soils without significant ecotoxicological risks. | [86] |
| Zinc oxide NPs (ZNONPs) | The potential of ZNO-NPs nanofertilizer to simultaneously reduce both As and Cd and nourishing rice tissues was tested in a greenhouse. The results highlight the ZNO-NPs nanofertilizer potential to reduce As and Cd in rice paddies, strengthening the key role of, and providing new insights into, the nanotechnology application in agriculture. | [87] |
| Flower-like magnetic MoS2 nanohybrid | The synthesis, characterization, and application of flower-like molybdenum disulfide decorated with iron oxide NPs (MoS2/Fe3O4) by a two-step hydrothermal method for the removal of Hg(II) and Pb(II) in the aqueous solution in the soil were described. Considerations on the facile preparation route, easy operation, and high removal efficiency of sulfide-based nanohybrid laid a foundation for the development of promising adsorbent strategies to remove heavy metals from wastewater and soils. | [88] |
| Biochar/iron (BC/Fe) composites | Biochar/iron (BC/Fe) composites revealed the interdependent effect of BC and Fe in soil and water remediation. The effect was owing to the mutual combination of Fe (adsorption, reduction, and oxidation) and BC (high surface area, rich functional groups, and high electron transfer efficiency). | [89] |
| Biogenic manganese oxide (BMO) materials | BMO was successfully used to stabilize arsenic in contaminated soil. The results also suggested BMO is a more efficient, cost-effective, and eco-friendly material compared to manganese oxide for remediation of arsenic. The study revealed a positive effect on the soil bacterial community biodiversity. | [90] |