Electrocatalytic dechlorination continually attracts attention in dealing with chlorinated volatile organic compounds (CVOCs) due to its mild reaction conditions, economical, and environmental friendliness. Unfortunately, the electrocatalysts were reported to suffer from low dechlorination reactivity and selectivity, as well as unclear active sites. Here, we developed a core–shell NiMn₂O₄ (NiMn₂O₄–CS) via a facile solvothermal method as an efficient cathode catalyst for selective dechlorination of 1, 2-dichloroethane (1,2-DCA) into highly valuable ethylene. NiMn₂O₄–CS provided more active sites that could accelerate electron transfer efficiency and fix more intermediate species (*CH₂CH₂Cl). The as-prepared electrode showed significant current density (18.11 mA/cm²) at a potential of −2.75 V (vs SCE) and an ethylene Faradaic efficiency of 41%. Transfer coefficient α points out a concerted mechanism of dechlorination. The first-principles calculations indicated that the Ni atoms in octahedral sites of NiMn₂O₄ are the main active sites for 1,2-DCA dechlorination to ethylene. In addition, a remarkable charge transfer appeared between the intermediate of *CH₂CH₂Cl and the Ni_oct sites of NiMn₂O₄. This work provides reasonable ideas for the design of dechlorination electrocatalysts and the friendly transformation of CVOCs.

中文翻译：

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锰基尖晶石核-壳纳米结构用于1,2-二氯乙烷的高效电催化

电催化脱氯由于其温和的反应条件，经济和环境友好性，在处理氯化挥发性有机化合物（CVOC）方面一直引起人们的关注。不幸的是，据报道，电催化剂的脱氯反应性和选择性低，并且活性位点不清楚。在这里，我们通过一种轻松的溶剂热方法开发了一种核壳型NiMn ₂ O ₄（NiMn ₂ O ₄ -CS），作为一种有效的阴极催化剂，用于将1,2-二氯乙烷（1,2-DCA）选择性脱氯成高价值的乙烯。NiMn ₂ O ₄ -CS提供了更多的活性位点，可以加快电子转移效率并固定更多的中间物种（* CH₂ CH ₂ Cl）。所制备的电极在-2.75 V（vs SCE）的电势下显示出显着的电流密度（18.11 mA / cm ²），乙烯法拉第效率为41％。传递系数α指出了脱氯的协调机制。第一性原理计算表明，NiMn ₂ O _4的八面体位点中的Ni原子是1,2-DCA脱氯成乙烯的主要活性位点。此外，* CH ₂ CH ₂ Cl的中间体与NiMn ₂ O ₄的Ni _oct位之间出现了显着的电荷转移。。这项工作为脱氯电催化剂的设计和CVOC的友好转化提供了合理的思路。