摘要
目的探究Si/BDD电极在酸性、碱性2种电解条件下的性能变化特征,阐明BDD电极在酸、碱溶液中电化学氧化性能的变化与失效机理。方法通过HFCVD技术制备Si/BDD电极,分别在1 mol/L H_(2)SO_(4)、1 mol/L NaOH溶液中进行加速寿命实验,以活性蓝19(RB-19)模拟染料废水,进行电化学氧化降解实验。使用扫描电子显微镜、拉曼光谱、接触角测试仪、紫外分光光度计及电化学工作站对电极的表面形貌、成分及电化学性能进行表征。结果在1 mol/L NaOH溶液中,当电解时间为195 h时,电极表面部分区域发生了明显的脱落现象;在1 mol/L H_(2)SO_(4)溶液中,当电解时间达到600 h时,电极表面仍未出现明显的脱落现象,电极表面形貌由清晰转为模糊,晶粒尺寸细化,且在晶界处存在明显的腐蚀现象;在酸溶液中,BDD电极对RB-19的降解效果随着电解时间的延长而提高,而在碱溶液中,其降解效果与电解10 h的降解效果基本一致。结论与酸溶液相比,Si/BDD电极更易在碱溶液中发生腐蚀。
Boron doped diamond electrode(BDD)is commonly considered as an ideal anode material for electrochemical oxidation treatment of wastewater.However,the surface of BDD encounters apparent corrosion when performing in concentrated acidic or basic conditions for a considerable time up to hundreds of hours.The work aims to comparatively investigate the change characteristics of electrochemical oxidation performance of the Si/BDD electrode in concentrated acidic(1 mol/L H_(2)SO_(4))or basic(1 mol/L NaOH)conditions via accelerated lifetime experiments under a constant current density of 1 A/cm^(2) at room temperature and expound the change and failure mechanism of electrochemical oxidation performance of BDD electrode in acidic or basic solutions.The two-electrode system was used,with a Si/BDD electrode(surface area of 4 cm^(2))and the stainless steel plate(with surface area equivalent to that of BDD)was adopted as the anode and cathode,respectively,and the distance between them was set as 10 mm.The cell voltage during the electrolysis process was recorded with time.The variations of cell voltage were used to assess the stability of the Si/BDD electrode.During electrochemical degradation tests,reactive blue 19(RB-19)was chosen as the simulated dye wastewater.The fixed volume of wastewater was taken out for further characterization of the dye concentration via UV-visible spectrophotometer according to the absorbance intensity.Scanning Electron Microscope(SEM)and Raman spectroscopy were performed to characterize the morphology and composition of the Si/BDD electrode.The hydrophilicity or hydrophobicity was assessed by contact angle measurement.The electrochemical potential window for water stability after different electrolytic conditions as well as electrolytic times was determined to further assess the stability of the Si/BDD electrode.The stability of the Si/BDD electrode in 1 mol/L H_(2)SO_(4) solution was different from that in 1 mol/L NaOH solution.After 195 h of electrolysis in a concentrated basic condition(i.e.,1
作者
白贺娜
王润
杨万林
陈伟鹏
邓泽军
魏秋平
李静
马莉
BAI He-na;WANG Run;YANG Wan-lin;CHEN Wei-peng;DENG Ze-jun;WEI Qiu-ping;LI Jing;MA Li(State Key Laboratory for Powder Metallurgy,Central South University,Changsha 410083,China;School of Materials Science and Engineering,Central South University,Changsha 410083,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2023年第5期121-130,共10页
Surface Technology
基金
国家重点研究发展计划(2021YFB3701803,2016YFB0301400)
国家自然科学基金(52071345,51874370)
广东省“十三五”重点研究开发项目(2020B01085001)
湖南省高新技术产业科技创新引领计划(2022GK4037,2022GK4047)。
关键词
掺硼金刚石电极
电化学氧化
电极稳定性
加速寿命实验
活性蓝19
boron doped diamond electrode
electrochemical oxidation
electrode stability
accelerated lifetime experiments
reactive blue 19
