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论文类型：期刊论文

发表时间：2019-01-30

发表刊物：ACS APPLIED MATERIALS & INTERFACES

收录刊物：SCIE、Scopus

卷号：11

期号：4

页面范围：3925-3936

ISSN号：1944-8244

关键字：heterogeneous electro-Fenton; porous polymeric frameworks; phase inversion; postsynthetic grafting; strong metal-support interaction

摘要：A facile postsynthetic amidoxime modification method was reported on the preparation of transition-metal ions (Mn, Fe, and Co)-polyacrylonitrile (PAN) polymeric beads complex as reusable catalysts for efficient and stable heterogeneous electro-Fenton oxidation. Through one-step phase inversion, low-cost and chemically resistant polymeric PAN beads were fabricated on a large scale with controllable sizes and abundant porous structure. The postfunctionalization strategy led more active sites to be uniformly distributed into modified PAN beads owing to the favorable channel confined effect and chelate coordination. Compared with pure PAN beads, the modified composite catalysts exhibited remarkably higher activity and stability in electro-Fenton oxidation over wide pH range of 3-10 without any addition of H2O2. By analysis, the grafted amidoxime group was extremely beneficial for improving metal loading and binding force between active sites and organic supports, which accelerated the active sites autocatalytic cycle to promote H2O2 activation by means of excited electron transfer from composites' functional groups. The catalytic activity of Mn-amidoximated PAN evaluated by the turnover frequency was 15 times more than that of traditional iron oxide and very competitive to the reported metal-organic framework-based composites. Moreover, a strong metal and polymeric support interaction significantly enhanced the stabilization of active sites dispersed in porous matrix and solved the ever-present problem of metallic ions leaching to the greatest extent. The scalable introduction of functionalities into sophisticated structures after host framework synthesis will bring valuable insights to develop highly efficient and stable heterogeneous catalysts for green electrochemical oxidation in practical application.