离子液体添加剂[BMIM]HSO4对锌电积过程析氧反应动力学的影响.pdf

物理化学学报( Wuli Huarue Xuebao)
J anuary
Acta Phys. -Chim. Sin, 2011, 27(1): 149-155
149
Article
www.whxb.pku.edu.cn
离子液体添加剂[BMIM]HSOa对锌电积过程析氧反应动力学的影响
张启波华一新
(离子液体冶金重点实验室,昆明理工大学治金与能源工程学院,昆明650093)
摘要:研究了1-丁基-3-甲基咪唑硫酸氢盐( BMIMHSO.)离子液体对锌电积过程析氧反应的影响.研究工作
借助于动电位极化,电化学阻抗谱,扫描电镜和X射线衍射等测试技术,动电位极化曲线及对应的动力学参数
分析表明,BMIM]HSO対阳极析氧反应具有催化作用,可提高析氧反应速率常数.电化学阻抗谱数据表明,
3MIMIHSO4能显著降低阳极析氧电荷传递电阻,在所研究的1.85-2.10V电位范围内添加5mg?L-[BMIM]
HSO,电阻值至少降低50%.此外,添加剂对阳极表面二次反应具有抑制作用,其在阳极表面的吸附,阻碍了阴
离子的阳极活化位点吸附过程.电化学测试结果与长时间(120h)阳极极化后所得阳极表面形貌和结晶取向分
析结果相一致.[ 3MIM] HSO. E的添加能有效抑制中间产物B-PbO2的形成,促进铅银电极表面大块且疏松多孔
a-PbO2的生成,加速阳极析氧的进行
关键词:电化学阻抗谱;锌电积;析氧;离子液体添加剂;表面形貌
中图分类号:O64
Effect of the onic Liquid Additive- B MLM]HSO on the Kinetics of
Oxygen Evolution during Zinc Electrowinning
ZHANG QI-BO HUA Yi-xin
( Key Laboratory of lonic Liquids Metallurgy, Faculty of Metallurgical and Energy Engineering,
Kunming University of Science and Technology, Kunming 6.50093, P R China
Abstract: The efe of te ion q i-m imidazolium hydrogen sulate(BMIM
HSO on the kinetics of oxygen evolution during zinc electrowinning from an acidic sulfate solution was
investigated. We used potentiodynamic polarization, electrochemical impedance spectroscopy, scanning
electron microscopy, and X-ray diffraction for this study. Potentiodynamic polarization curves and the
corresponding kinetic parameter analysis show that [BMIM]HSO has a catalytic effect on oxygen
evolution by stimulating te reaction rate constant Impedance data reveal that [BMM]HSO. can markedly
reduce the ox gen evolution charge transfer resistance. The addition of 5 mgL [BMIM HSO obviously
decreased the resistance value by at least 50% over the studied potential range from 1.85 to 2.10. In
addition, the results of the impedance measurements also suggest an inhibition effect of [BMIM]HSO on
the secondary reactions and this is due to the adsorption of the additive on the anode surface, which
decreased the amount of active sites for anion adsorption. All electrochemical results were corroborated
with a morphological and orientation analysis of the anodic surface after 120 h of anodic polarization. The
addition of [BMIM]HSO inhibited the generation of the intermediate product 8-pbo2 and it promoted the
generation of larger, loose, and porous a-pbo2, which benefited the oxygen evolution reaction
Received September 30, 2010; Revised: November 16, 2010; Published on Web: December 8,2010
CorrespondingauthorEmail:qibozhang@yahoo.com.cn;Tel:+86-871-5162008
The project was supported by the National Natural Science Foundation of China(50864009, 50904031 )and Research Fund for the Doctoral Program
of Higher Education of China (20070674001
国家自然科学基金(50864009,50904031)及高等学校博上学科点专顼科研基金(20070674001)资助项目
C Editorial officc of Acta Physico-chimica Sinica