CAJ | 학술논문

采用动电位极化、循环伏安、电流暂态和阻抗等技术研究钽在四丁基硫酸氢铵(TBAHS)乙醇溶液中的电化学行为.研究结果表明:循环伏安曲线中没有活化-钝化转变,阳极电流密度随溶液温度、TBAHS浓度、电位扫描速率和水含量增加而增加;表观活化能为43.389 kJ/mol,溶解过程为扩散控制.恒电位测试结果表明,当电位较低时,电流密度逐渐降至一稳定值;当电位高于某一值时,电流密度最初下降至一最小值然后逐渐增加.钝化膜电阻随电位升高而减小,当电位高于2.0 V时,出现感抗弧.
채용동전위겁화、순배복안、전류잠태화조항등기술연구단재사정기류산경안(TBAHS)을순용액중적전화학행위.연구결과표명:순배복안곡선중몰유활화-둔화전변,양겁전류밀도수용액온도、TBAHS농도、전위소묘속솔화수함량증가이증가;표관활화능위43.389 kJ/mol,용해과정위확산공제.항전위측시결과표명,당전위교저시,전류밀도축점강지일은정치;당전위고우모일치시,전류밀도최초하강지일최소치연후축점증가.둔화막전조수전위승고이감소,당전위고우2.0 V시,출현감항호.
The electrochemical behaviors of Ta in tetrabutylammonium hydrogen sulfate (TBAHS) ethanol solutions were studied using potentiodynamic polarization, cyclic voltammetry, potentiostatic current time transient and impedance techniques. The results revealed that no active-passive transition is presented in the cyclic voltammogram, and the anodic current density increases with the increase of solution temperature, TBAHS concentration, potential scan rate and water content. The apparent activation energy is about 43.389 kJ/mol and the dissolution process is diffusion-controlled. Potentiostatic measurements showed that the current density gradually decays to a steady value when the potential is low; however, when the potential is higher than a certain value, the current density initially declines to a minimum value and then increases gradually. The resistance of passive film decreases with increasing potential, and inductive loops are presented when the potential is higher than 2.0 V.