Electrocatalytic degradation of 2,4-dichlorophenol by a 3DG-PbO2 powdered anode: Experimental and theoretical insights
Electrocatalytic degradation of 2,4-dichlorophenol by a 3DG-PbO2 powdered anode: Experimental and theoretical insights
复制标题
3DG-PbO2 粉末阳极电催化降解 2,4-二氯苯酚：实验和理论见解
DOI：
10.1016/j.seppur.2021.120003
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发表时间：
2021-11-08
影响因子：
8.6
通讯作者：
Chang, Limin
中科院分区：
文献类型：
--
作者：
Duan, Xiaoyue;Wang, Qian;Chang, Limin
我们之前的研究中制备了一种新型纳米粉末PbO2（NP-PbO2）电极作为高效电催化氧化阳极材料，但它仍然受到高电荷转移电阻的挑战。本文将三维石墨烯（3DG）与NP-PbO2复合来解决这个问题。由于3DG提供的多维电传输通道，NP-PbO2的电荷转移电阻从3.08 x 10(5)大幅降低至7.74 x 10(3) omega/cm(2)，从而显着提高了NP-PbO2电极的羟基自由基产生能力。在2,4-二氯苯酚(2,4-DCP)的电催化氧化过程中，最优的3DG-PbO2复合阳极表现出优异的电催化活性。电解60分钟后，3DG-PbO2电极的矿化电流效率分别是NPPbO2和电沉积PbO2（ED-PbO2）电极的1.68和3.38倍。检查了几个重要操作参数对 2,4-DCP 去除效率的影响。结果表明，在电流密度4 mA/cm(2)、2,4-DCP初始浓度50 mg/L、pH 3、Na2SO4浓度0.05 M条件下，电解80 min后2,4-DCP去除率达到97.67%。此外，通过理论计算（前沿分子轨道、分子静电势、总静电势、总静电势等）探讨了2,4-DCP的降解机理。 电荷、福井函数和瞬态）和中间体的实验鉴定。因此，我们提出了 3DG-PbO2 阳极上 2,4-DCP 的矿化途径。
A novel nano powdered PbO2 (NP-PbO2) electrode was fabricated in our previous study as a highly efficient anode material for electrocatalytic oxidation, but it is still challenged by its high charge transfer resistance. Herein, three-dimensional graphene (3DG) was composited with NP-PbO2 to solve this problem. Due to the multidimensional electrical transmission channels provided by 3DG, the charge transfer resistance of NP-PbO2 was greatly reduced from 3.08 x 10(5) to 7.74 x 10(3) omega/cm(2), thereby significantly boosting the hydroxyl radical generation capacity of NP-PbO2 electrode. In electrocatalytic oxidation process of 2,4-dichlorophenol (2,4-DCP), the optimal 3DG-PbO2 composite anode exhibited excellent eletrocatalytic activity. After 60 min of electrolysis, the mineralization current efficiency at 3DG-PbO2 electrode was 1.68 and 3.38 times higher than those at NPPbO2 and electrodeposited PbO2 (ED-PbO2) electrodes, respectively. The influence of several important operation parameters on the 2,4-DCP removal efficiency was examined. The results show that the 2,4-DCP removal reached 97.67% after 80 min of electrolysis under the conditions of current density 4 mA/cm(2), initial 2,4-DCP concentration 50 mg/L, pH 3 and Na2SO4 concentration 0.05 M. In addition, the degradation mechanism of 2,4DCP was explored via theoretical computation (frontier molecular orbitals, molecular electrostatic potential, total charges, Fukui functions and transient states) and experimental identification of intermediates. Accordingly, we proposed the mineralization pathway of 2,4-DCP at the 3DG-PbO2 anode.