论文部分内容阅读
利用循环伏安(CV)、计时安培(CA)和电化学阻抗(EIS)研究了纳米Al2O3颗粒在不同电位(vs.SCE)下对Ni自硫酸盐镀液在铜基体上电沉积的影响。结果表明,Ni-Al2O3体系共沉积的起始电位为:–740mV左右;在不同的电位下,纳米-Al2O3颗粒对镍沉积过程的影响有所差别;在电位–740～–830mV范围,与纯Ni沉积相比较,Ni-Al2O3体系沉积的峰电流所对应的孕育期tm明显缩短,反映Al2O3颗粒在阴极表面有利于镍沉积成核,且促进了电结晶成核。Al2O3颗粒吸附在阴极表面可能会阻碍部分离子电荷放电和物质传输过程,尤其在电位–250～–650mV范围,致使Ni-Al2O3体系沉积阻抗增加。在较高的过电位下,Al2O3颗粒的促进作用有所减弱,许多颗粒堆积在电极表面上还可能减小Ni-Al2O3沉积的还原反应电流。在电位–890mV,Ni-Al2O3体系电沉积初期阶段的成核过程基本遵循三维的Scharifker-Hill瞬时成核模式。
The effects of nano-sized Al2O3 particles on the electrodepositing of Ni self-sulfate bath on Cu matrix were investigated by cyclic voltammetry (CV), chronopotentiometer (AAC) and electrochemical impedance spectroscopy (EIS) at different potentials (vs.SCE). The results show that the initial potential of co-deposition of Ni-Al2O3 system is about -740mV. Under different potentials, the effect of nano-Al2O3 particles on the deposition of nickel is different. In the range of -740 ~ -830mV, Compared with Ni deposition, the tm corresponding to the peak current deposited by the Ni-Al2O3 system was significantly shortened, which indicated that the Al2O3 particles favored the nucleation of Ni deposition on the cathode surface and promoted the nucleation of the electrocrystallization. Al2O3 particles adsorbed on the cathode surface may hinder part of the ionic charge discharge and material transport process, especially in the potential -250 ~ -650mV range, resulting in Ni-Al2O3 system deposition resistance increases. At higher overpotential, the accelerating effect of Al2O3 particles is weakened, and many particles deposited on the electrode surface may also reduce the reduction reaction current of Ni-Al2O3 deposition. At potential of -890 mV, the nucleation process in the initial stage of electrodeposition of Ni-Al2O3 system basically follows the three-dimensional Scharifker-Hill transient nucleation mode.