硫酸鈉與硼酸溶液對導電玻璃ITO上鍍鈷的影響

Abstract

本研究探討硫酸鈉與硼酸溶液對導電玻璃ITO上鍍鈷的影響。以循環伏安法找出適合的電鍍電壓，並改變不同的電解質輔助液探討對鈷膜表面的影響。我們藉由金相顯微鏡、原子力顯微鏡對鈷膜表面進行觀察，再以固定電鍍電壓的方式，分析得到電流對時間的關係，判定鈷在ITO上為接近瞬時成核的機制，並利用磁光柯爾效應測量鈷膜的磁性。 在實驗的過程中我們發現，電解質輔助液硫酸鈉以及硼酸各有其優缺點，硫酸鈉幫助我們決定所需要電鍍的電壓以及增加還原電流，硼酸輔助液不僅可以抑制產生Co的氫氧化物，它還能讓薄膜均勻成長。我們發現硼酸的濃度明顯影響Co島的結構，並進而改變磁性之量測結果。

The effects of sodium sulfate (Na2SO4) and boric acid (H3BO3) solution on coating cobalt onto the ITO were investigated by cyclic voltammetry (CV), metallurgical microscopy, atomic force microscope (AFM) and magneto-optical Kerr effect (MOKE). We looked for the proper plating voltage of Co by CV studies; we observed the topography of Co films by optical microscope and AFM. During the electrodeposition process, we monitored the relationship between current and time by chronoamperometry (CA). From analyzing the CA curves, we determined that the growth kinetic of the Co onto ITO substrate was approximately instantaneous nucleation mechanism. The data clearly shows that adding Na2SO4 is helpful for us to determine the proper voltage of deposition Co; it also increases the reduction current. Adding H3BO3 not only inhibits the reduction of Co hydroxide but also helps the Co nuclei to uniformly distribute on the ITO surface. The concentration of H3BO3 significantly affects the structure and varies the magnetic properties of the Co nuclei.