Key Laboratory of Pollution Process and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Urban Ecology Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
Environ Sci Pollut Res Int. 2014;21(14):8476-84. doi: 10.1007/s11356-014-2792-0. Epub 2014 Apr 1.
A series of lead dioxide electrodes developed on titania nanotube arrays with different matrix were fabricated by electrodeposition. Before the deposition of PbO₂, the matrix of this anode was electrochemically reduced in (NH₄)₂SO₄ solution and/or pre-deposited with certain amounts of copper. To gain insight into these pretreatments, the PbO₂ electrodes were characterized by SEM, LSV, and XRD, and their electrocatalytic activities for pollutant degradation were compared using p-nitrophenol (p-NP) as a model. It was confirmed that the electrochemical reduction with (NH4)₂SO₄ resulted in the partial conversion of TiO₂ into Ti₄O₇ and Ti₅O₉, which increased the conductivity of PbO₂ anode, but decreased its electrochemical activity, while the Ti/TNTs*-Cu/PbO₂ electrode with both pretreatments possessed the highest oxygen evolution overpotential of 2.5 V (vs. SCE) and low substrate resistance. After a 180-min treatment on this electrode, the removal efficiency of p-NP reached 82.5% and the COD removal achieved 42.5% with the energy consumption of 9.45 kWh m(-3), demonstrating the best performance among these electrodes with different matrices. Therefore, this titania nanotube array-based PbO₂ electrode has a promising application in the industrial wastewater treatment.
采用电化学沉积法在不同基底的 TiO₂ 纳米管阵列上制备了一系列二氧化铅电极。在沉积 PbO₂ 之前，该阳极的基底在（NH₄）₂SO₄ 溶液中进行电化学还原，和/或预先沉积一定量的铜。为了深入了解这些预处理，通过 SEM、LSV 和 XRD 对 PbO₂ 电极进行了表征，并使用对硝基苯酚（p-NP）作为模型比较了它们对污染物降解的电催化活性。证实（NH₄）₂SO₄ 的电化学还原导致部分 TiO₂ 转化为 Ti₄O₇ 和 Ti₅O₉，从而提高了 PbO₂ 阳极的导电性，但降低了其电化学活性，而经过两种预处理的 Ti/TNTs*-Cu/PbO₂ 电极具有最高的析氧过电位 2.5 V（相对于 SCE）和低的基底电阻。在该电极上处理 180 min 后，p-NP 的去除效率达到 82.5%，COD 去除率达到 42.5%，能耗为 9.45 kWh m(-3)，在具有不同基底的这些电极中表现出最佳性能。因此，基于 TiO₂ 纳米管阵列的 PbO₂ 电极在工业废水处理中有很好的应用前景。
