(1. 蘭州理工大學(xué) 省部共建有色金屬先進(jìn)加工與再利用國(guó)家重點(diǎn)實(shí)驗(yàn)室，蘭州 730050；
2. 鎳鈷資源綜合利用國(guó)家重點(diǎn)實(shí)驗(yàn)室，金昌 737100)
摘 要: 研究銅離子濃度對(duì)工業(yè)電解液中鎳電結(jié)晶過(guò)程的影響。采用傳統(tǒng)三電極體系，通過(guò)陰極極化法、循環(huán)伏安法、計(jì)時(shí)電流法分析銅離子對(duì)鎳電結(jié)晶初期行為的影響。利用電位階躍和霍爾槽實(shí)驗(yàn)制備沉積層并通過(guò)SEM觀察其微觀組織形貌，通過(guò)XRD分析其擇優(yōu)生長(zhǎng)取向。結(jié)果表明：不同質(zhì)量濃度銅離子的加入使得鎳電結(jié)晶過(guò)電位降低，鎳的起始沉積電位發(fā)生正移，但并不改變鎳形核/長(zhǎng)大的生長(zhǎng)方式。銅離子的加入使鎳形核弛豫時(shí)間tm逐漸縮短，峰電流Im逐漸增大；當(dāng)銅離子質(zhì)量濃度為0.5和1.0 g/L、階躍電位為-0.85 V時(shí)，鎳電結(jié)晶處于三維連續(xù)形核和三維瞬時(shí)形核之間；當(dāng)階躍電位處于-0.90~-1.00 V時(shí)，接近于三維瞬時(shí)形核。隨著銅離子濃度增大到1.5 g/L、2.0 g/L時(shí)，鎳電結(jié)晶由三維連續(xù)形核轉(zhuǎn)變?yōu)槿S瞬時(shí)形核；鎳-銅電解液在電沉積過(guò)程中更適用于三維瞬時(shí)形核/生長(zhǎng)機(jī)制。隨著銅離子的引入，鎳和銅發(fā)生共沉積，沉積層晶粒尺寸變大；沉積層的形貌由最初的小圓球顆粒逐漸變?yōu)榻鹱炙睿L(zhǎng)方式以螺旋位錯(cuò)生長(zhǎng)方式為主，晶粒逐漸由(111)面轉(zhuǎn)變?yōu)?111)、(220)面生長(zhǎng)。
關(guān)鍵字: 鎳；工業(yè)電解液；銅離子；電結(jié)晶行為
（1. State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metal, Lanzhou University of Technology, Lanzhou 730050, China;
2. State Key Laboratory for Comprehensive Utilization of Nickel and Cobalt Resources, Jinchang 737100, China）
Abstract:In order to study the effect of different concentrations of copper ions on the electrocrystallization behavior of nickel in industrial electrolytes, the traditional three-electrode system was used to analyze the effect of copper ions on the initial behavior of nickel electrocrystallization through cathodic polarization, cyclic voltammetry and chronoamperometry. The microstructure morphology was observed by SEM using chronoamperometry and Hall cell experiment, and the preferred growth orientation was analyzed by XRD. The results show that the addition of copper ions with different mass concentrations decreases the electrocrystallization overpotential of nickel and the initial deposition potential of nickel shifts positively, which does not change the mode of nickel through the way of nucleation/growth. The addition of copper ions gradually reduces the nucleation relaxation time tm, and the peak current Im gradually increases. When the copper ion mass concentrations are 0.5 and 1.0 g/L, and the step potential is -0.85 V, nickel electrocrystallization is between the three-dimensional continuous nucleation and the three-dimensional instantaneous nucleation; when the step potential is -0.90－-1.00 V, nickel electrocrystallization is close to instantaneous nucleation. As the copper ion concentration increases to 1.5 g/L and 2.0 g/L, nickel electrocrystallization changes from the three-dimensional continuous nucleation to the three-dimensional instant nucleation. Nickel-copper electrolyte is more suitable for three-dimensional instantaneous nucleation/growth mechanism during electrodeposition. With the introduction of different mass concentrations of copper ions, nickel and copper are co-deposited, the grain size becomes larger. The morphology of the sedimentary layer gradually changes from the original small spherical particles to pyramid shape, and the growth mode is still dominated by screw dislocation growth. The grain orientation changes from (111) plane to (111), (220) plane.
Key words: nickel; industrial electrolyte; copper ions; electrocrystallization behavior
