title: Hydroxyl multi-walled carbon nanotube-modified nanocrystalline PbO2anode for removal of pyridine from wastewater.
abstract: We prepared a hydroxyl multi-wall carbon nanotube-modified nanocrystalline PbO2anode (MWCNTs-OH-PbO2) featuring high oxygen evolution potential, large effective area, and excellent electrocatalytic performance. The oxygen evolution potential and effective area of the MWCNTs-OH-PbO2electrode were 1.5 and 3.7-fold higher than the traditional PbO2electrode. Electrochemical degradation of pyridine in aqueous solution was investigated by using the MWCNTs-OH-PbO2anode. Based on pyridine decay rate (93.8%), total organic carbon reduction (84.6%), and energy consumption (78.8WhL-1order-1) under the optimal conditions, the MWCNTs-OH-PbO2electrode modified with MWCNTs-OH concentration of 1.0gL-1exhibited higher electrochemical oxidation ability than the traditional PbO2electrode. The intermediate, hydroxypyridine, was found at the first stage of electrolysis. The primary mineralization product, NO3-, was detected in aqueous solution after electrolysis. A possible electrochemical mineralization mechanism including two potential routes, i.e., via formation of small organic molecules by ring cleavage reaction and direct mineralization to CO2and NO3-, was proposed. The results demonstrated that the MWCNTs-OH-PbO2electrode exhibited high efficiency for pyridine mineralization in aqueous solution under mild conditions.
authors.affiliation: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China.
authors.forename: Zesheng
authors.initials: Z
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China.
authors.forename: Han
authors.initials: H
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China; School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, Guangdong 523808, PR China. Electronic address: junfengn@bnu.edu.cn.
authors.forename: Junfeng
authors.initials: J
authors.lastname: Niu
authors.affiliation: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China.
authors.forename: Yijing
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China.
authors.forename: Chong
authors.initials: C
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, PR China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wang
keywords: Electrochemical mineralization; Multi-walled carbon nanotube; PbO(2); Pyridine; Wastewater