School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, PR China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, 430072, China.
School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, PR China.
Water Res. 2021 Dec 1;207:117802. doi: 10.1016/j.watres.2021.117802. Epub 2021 Oct 26.
Atomic hydrogen (H•) is highly reactive for the hydrodechlorination of trichloroethylene (TCE). In this work, we found that the coprecipitation of Ni and Fe at neutral pH led to an unprecedented catalytic generation of H•. The generated H• effectively dechlorinate TCE to nontoxic ethylene and ethane, and Fe is the only electron donor. The abundant adsorbed H• produced with a Ni/Fe ratio of 0.4 enhances hydrogen evolution reaction causing a low efficiency for hydrodechlorination. In contrast, the active absorbed H• is generated in the crystal lattice of Ni-Fe hydroxides with a Ni/Fe ratio of 3.0 causing highly efficient hydrodechlorination of TCE. This work not only reveals the mechanism of catalytic hydrodechlorination by Ni-Fe hydroxides at neutral pH, but also provides a novel approach to detoxify TCE in contaminated water using facile precipitated Ni-Fe hydroxides.
原子氢（H•）对三氯乙烯（TCE）的氢化脱氯具有高度反应性。在这项工作中，我们发现 Ni 和 Fe 在中性 pH 下共沉淀导致了 H•的前所未有的催化生成。生成的 H•有效地将 TCE 脱氯为无毒的乙烯和乙烷，而 Fe 是唯一的电子供体。Ni/Fe 比为 0.4 时产生的大量吸附 H•促进了析氢反应，导致氢化脱氯效率低下。相比之下，Ni/Fe 比为 3.0 时，活性吸附 H•在 Ni-Fe 氢氧化物晶格中生成，从而实现了 TCE 的高效氢化脱氯。这项工作不仅揭示了中性 pH 下 Ni-Fe 氢氧化物催化氢化脱氯的机制，还提供了一种使用简便沉淀的 Ni-Fe 氢氧化物来净化受污染水中 TCE 的新方法。
