Fenton reaction has important implications in biology- and environment-related remediation. Hydroxyl radicals (^•OH) and hydroxide (OH^–) were formed by a reaction between Fe(II) and hydrogen peroxide (H₂O₂). The acidic H₂O₂/Fe(II/III) redox-induced low H₂O₂ utilization efficiency is the bottleneck of Fenton reaction. Electron paramagnetic resonance, surface-enhanced Raman scattering, and density functional theory calculation indicate that the unpaired electrons in the defects of carbon quantum dots (CQDs) and the carboxylic groups at the edge have a synergistic effect on CQDs Fenton-like catalysis. This leads to a 33-fold higher H₂O₂ utilization efficiency in comparison with Fe(II)/H₂O₂ Fenton reaction, and the pseudo-first-order reaction rate constant (k_obs) increases 38-fold that of Fe(III)/H₂O₂ under equivalent conditions. The replacement of acidic H₂O₂/Fe(II/III) redox with CQD-mediated Fe(II/III) redox improves the sluggish Fe(II) generation. Highly effective production of ^•OH in CQDs-Fe(III)/H₂O₂ dramatically decreases the selectivity of toxic intermediate benzoquinone. The inorganic ions and dissolved organic matter (DOM) in real groundwater show negligible effects on the CQDs Fenton-like catalysis process. This work presents a process with a higher efficiency of utilization of H₂O₂in situ chemical oxidation (ISCO) to remove persistent organic pollutants.

中文翻译：

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通过碳量子点类芬顿催化克服酸性 H2O2/Fe(II/III) 氧化还原引起的 H2O2 低利用效率

Fenton 反应在生物学和环境相关的修复中具有重要意义。羟基自由基 ( ^• OH) 和氢氧化物 (OH ^– ) 由 Fe(II) 和过氧化氢 (H ₂ O ₂ ) 之间的反应形成。酸性H ₂ O ₂ /Fe(II/III)氧化还原导致H ₂ O ₂利用率低是Fenton反应的瓶颈。电子顺磁共振、表面增强拉曼散射和密度泛函理论计算表明，碳量子点（CQDs）缺陷中的未配对电子与边缘羧基对CQDs类芬顿催化具有协同作用。这导致 H 高出 33 倍₂ O ₂利用效率与Fe(II)/H ₂ O ₂ Fenton反应相比，准一级反应速率常数( k _{obs )是Fe(III)/H 2} O ₂的38倍同等条件。用 CQD 介导的 Fe(II/III) 氧化还原代替酸性 H ₂ O ₂ /Fe(II/III) 氧化还原改善了缓慢的 Fe(II) 生成。在 CQDs-Fe(III)/H ₂ O ₂中高效生成^{• OH}大大降低了有毒中间体苯醌的选择性。实际地下水中的无机离子和溶解有机物 (DOM) 对 CQDs 类 Fenton 催化过程的影响可以忽略不计。这项工作提出了一种利用 H ₂ O ₂原位化学氧化 (ISCO) 去除持久性有机污染物的效率更高的工艺。