Biphase Co@C core-shell catalysts for efficient Fenton-like catalysis.
Biphase Co@C core-shell catalysts for efficient Fenton-like catalysis.
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DOI：
10.1016/j.jhazmat.2022.128287
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发表时间：
2022-01
影响因子：
13.6
通讯作者：
Yongsong Ma;K. Du;Yifan Guo;Mengyi Tang;Huayi Yin;X. Mao;Dihua Wang
中科院分区：
文献类型：
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作者：
Yongsong Ma;K. Du;Yifan Guo;Mengyi Tang;Huayi Yin;X. Mao;Dihua Wang
尽管Co纳米粒子在类Fenton系统中的催化氧化在消除污染物方面具有重要作用，但Co相的贡献通常被忽视。本文采用熔融碳酸盐体系中CaCO3和Co3O4电化学共还原的方法合成了Co@C两相核壳催化剂。与传统的700℃以上的热解方法不同，电解温度为450℃，可以获得面心立方(FCC)和六方密排(HCP)结构的两相结构。Co@C两相催化剂对邻苯二甲酸二乙酯表现出优良的催化氧化性能，具有较高的转化率(TOF，28.14min-1)和低催化剂用量(4 mg/L-1)。此外，密度泛函理论(DFT)计算证实，Co@C两相的协同催化作用是增强了过氧化氢O-O键的断裂和催化剂向PMS分子的电荷转移。此外，自由基猝灭实验和电子顺磁共振(EPR)测试结果证实，SO4·-、·OH、O2·-和1O2共降解DEP。在纯净水和实际河水中，DEP、磺胺甲恶唑(SMX)和2，4-二氯酚(2，4-DCP)三种模型污染物的去除效果均达到100%。本论文提供了一种利用催化剂的物相，从而调节其修复难降解有机污染物的催化能力的电化学途径。
Despite the vital roles of Co nanoparticles catalytic oxidation in the Fenton-like system for eliminating pollutants, contributions of Co phases are typically overlooked. Herein, a biphase Co@C core-shell catalyst was synthesized by the electrochemical co-reduction of CaCO3and Co3O4in molten carbonate. Unlike the traditional pyrolysis method that is performed over 700 °C, the electrolysis was deployed at 450 °C, at which biphase structures, i.e., face-centered cubic (FCC) and hexagonal close-packed (HCP) structures, can be obtained. The biphase Co@C shows excellent catalytic oxidation performance of diethyl phthalate (DEP) with a high turnover frequency value (TOF, 28.14 min–1) and low catalyst dosage (4 mg L–1). Furthermore, density functional theory (DFT) calculations confirm that the synergistic catalytic effect of biphase Co@C is the enhancement for the breaking of the peroxide O–O bond and the charge transfer from catalysts to PMS molecule for the activation. Moreover, the results of radicals quenching experiments and electron paramagnetic resonance (EPR) tests confirm that SO4•–, •OH, O2•–, and1O2co-degrade DEP. Remarkably, 100% removals of three model contaminants, including DEP, sulfamethoxazole (SMX) and 2,4-dichlorophen (2,4-DCP), were achieved, either in pure water or actual river water. This paper provides an electrochemical pathway to leverage the phase of catalysts and thereby mediate their catalytic capability for remediating refractory organic contaminants.