同济大学赵国华团队提出了碳气凝胶包覆FeCo合金通过3-电子途径选择性电催化氧还原为羟基自由基快速彻底去除污染物的策略。 相关研究成果于2021年2月19日发表在《德国应用化学》。

研究人员报道了用碳气凝胶（FeCoC）包覆的FeCo合金，通过3电子途径将氧（O₂）选择性电化学还原为羟基自由基（·OH）。暴露-COOH的石墨壳层有利于H₂O₂生成的2电子还原途径由1电子向·OH逐步还原。利用FeCo合金内部的电子调节碳壳层的局部电子环境，可以调节其电催化活性。电催化还原O2生成·OH的新策略克服了Fenton过程中还原/氧化态循环引发的电子转移的限速步骤。

在该系统中，在5min内快速完全去除了环丙沙星，表观速率常数（k obs）高达1.44±0.04min^-1，与最新的高效氧化工艺相当。连续运行50次后，降解率基本保持不变，表明其在实际应用中具有良好的稳定性。

附：英文原文

Title: Selective electrocatalytic reduction of oxygen to hydroxyl radicals via 3‐electron pathway with FeCo alloy encapsulated carbon aerogel for fast and complete removing pollutants

Author: Fan Xiao, Zining Wang, Jiaqi Fan, Tetsuro Majima, Hongying Zhao, Guohua Zhao

Issue&Volume: 2021-02-19

Abstract: We reported selective electrochemical reduction of oxygen (O  2  ) to hydroxyl radicals (·OH) via 3‐electron pathway with FeCo alloy encapsulated by carbon aerogel (FeCoC). The graphite shell with exposed –COOH is conducive to the 2‐electron reduction pathway for H  2  O  2  generation stepped by 1‐electron reduction toward to ·OH. The electrocatalytic activity can be regulated by tuning the local electronic environment of carbon shell with the electrons coming from the inner FeCo alloy. The new strategy of ·OH generation from electrocatalytic reduction O  2  overcomes the rate‐limiting step over electron transfer initiated by reduction‐/oxidation‐state cycle in Fenton process. Fast and complete removal of ciprofloxacin was achieved within 5 min in this proposed system, the apparent rate constant (  k  obs  ) was up to 1.44 ± 0.04 min  ‐1  , which is comparable with the state‐of‐the‐art advanced oxidation processes. The degradation rate was almost remained the same after 50 successive runs, suggesting the satisfactory stability for practical applications.

DOI: 10.1002/anie.202101804

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202101804