本研究中使用電化學法於多孔鎳上沉積氫氧化鈷，並於1M氫氧化鉀中進行電容研究。多孔鎳製作方式是使用定電位法，把鎳片做為工作電極於銅鎳共鍍液中(0.01 M 硫酸銅+1M硫酸鎳，pH=4) 沉積電位為 -0.75V ( V vs SCE)沉積電量為三庫侖得到之銅鎳鍍層，進一步於0.1V進行選擇性溶解將溶解銅鎳鍍層中的銅而得，由SEM照片可知道使用電化學法得到的多孔鎳電極具有高表面積，因此也能提供化學反應較多的反應位置。
在氫氧化鈷的陰極沉積實驗中使用的電鍍液是0.1M醋酸鈷，並將沉積電位設在-0.75V，沉積電量為50 mC。使用XPS進行分析可在781.2 eV可觀察到氫氧化鈷相對應的鍵結能，AA分析得知氫氧化鈷陰極沉積的電流效率為95%。將得到的氫氧化鈷電極置於1M氫氧化鉀中進行電容測試，得到最高電容值為2915.7 Fg-1(掃描速率5 mVs-1)，得到的數值高於基材為拋光鎳片的氫氧化鈷電容器 (以拋光鎳為基材的氫氧化鈷電極在掃描速率為5 mVs-1得到的高電容為 544.4 Fg-1)，即使將掃描速率增加到200 mVs-1，此電容器仍可達到最高電容量的86%。另外，使用定電流(0.166 mA cm-2)進行充放電測試，可觀察到最高電容值為2538.2 Fg-1，甚至將充電速率提升至原先的八倍(1.328 mA cm-2)此電容依然呈現高電容值，這是因為高表面積的多孔結構，縮短了電極表面與電解液之間的距離，因此提升了電解液的質傳速度，使得此電容器在快速充放電下仍能保持高效能，說明了此電容器可運用在需要快速充放電的電子元件上。最後，將基材為多孔鎳的氫氧化鈷電容器進行重複的循環測試，可發現即使經過兩千次循環掃描，氫氧化鈷電極上鈷的含量仍保持96%，顯示此電容器具有較高的電化學穩定性。
使用XPS將氫氧化鈷的初鍍層以及經過400循環掃描以後之氫氧化鈷電極進行XPS分析，觀察Co2p3/2、 Ni2p3/2以及O1s可得知氫氧化鈷出鍍層完整覆蓋多孔鎳表面，而經過400次循環掃描以後無論是從Co2p3/2、 Ni2p3/2或者是O1s都可觀察到氫氧化鈷以及多孔鎳隨著長時間掃描而被氧化，而這也是循環伏安圖中觀察到的氫氧化鈷電極經過多次循環掃描以後第二對氧化還原峰(~0.35 V，掃描速率為50 mV s-1)反應電流增加的原因，推測是因為隨著循環掃描而生成鈷的氧化物以及鎳的氧化物逐漸嵌入彼此的晶格中形成Co-Ni複合物，因而增加了電極的導電性，使得反應電流呈現大幅度的增加。儘管，在本研究中並無直接證據可證明Co-Ni複合物的存在，但相信在未來的研究中可利用進一步的研究來嘗試證明此論述。

Cobalt hydroxides deposited on porous nickel by electrochemical method was investigated in 0.1M cobalt acetate in this study. And the pseudocapacitive behavior of cobalt hydroxide electrode was studied in 1M KOH. The substrate named porous nickel was fabricated with two steps. In the first step: Prepared the Cu-Ni deposits with the method-chronopotentiometry. Set nickel foil as the working electrode in the Cu - Ni codeposition solution ( 0.01 M CuSO4 + 1M NiSO4 + H3BO4, pH= 4 ), deposition potential -0.75V (V vs SCE) was set, and the total deposition charges were 3 coulomb. And in second step : The nickel with high porosity was resulted from selective dissolution at 0.1 V( V vs SCE ) to dissolving the element Cu in the Cu-Ni deposits. From SEM images, porous structures could be observed that revealed more active sites could provide for absorption or chemical reactions.
Co(OH)2 was deposited on porous nickel in 0.1 M Co(CH3COO)2 and the deposition conditions -0.75 V (V vs SCE) , 50 mC was set. The deposits were charactered by X-ray Photoelectron Spectroscopy and the binding energy of Co2p3/2 at 781.2 eV for Co(OH)2 was showed. As-prepared Co(OH)2 electrode was studied pseudocapacitive behavior systematically in 1M KOH with cyclic voltammetry and constant current density for charging - discharging test. The maximum of the specific capacitance 2915.7 Fg-1 was obtained in the potential range between -0.2 V to 0.45 V from cyclic voltammetry at scan rate equaled 5 mVs-1 (and exchanged substrate with polished nickel, the maximum of specific capacitance of Co(OH)2 electrode was544.4 Fg-1), and even enhanced scan rate as high as 200 mVs-1, it still showed high capacity value about 2795.4 Fg-1. In the constant current density for charging - discharging test, 2538.2 Fg-1 was achieved as the highest specific capacitance at a galvanostatic current density of 0.166 mA cm-2 in the potential range from -0.2 V to 0.45 V. Even thought increased the discharging current density to eight times high (1.328 mA cm-2), it still presented high capacitance (1956.7 Fg-1). As high as specific capacity value suggested to porous structure that improved the mass transportation of electrolyte to the electrode and accelerated electronic conduction of electrode material.
Finally, the electrochemical stability of Co(OH)2 electrode was studied in 1M KOH at the scan rate equaled 5mVs-1. From the atomic adsorption analysis, the composition of Co(OH)2 electrode still maintained about 96% of Co(OH)2 after 2000 cycles in the basic media, it revealed good electrochemical stability for this Co(OH)2 electrode.From the XPS spectrum of the Co2p3/2, Ni2p3/2 and O1s orbitals of the as-deposited Co(OH)2 electrode and the Co(OH)2 electrode which repeated cyclic processes about 400 cycles in 1 M KOH. The Co(OH)2 electrode were oxidized during cyclic processes gradually were shown that contributed the second pair of redox peak increased noticeably at about 0.35V (scan rate were 50 mV s-1). It might assume the molecules size of cobalt oxide, cobalt hydroxide, nickel and nickel hydroxide were so close that formed Co-Ni oxide / hydroxide complex compound that further enhanced the conductivity of the Co(OH)2 electrode. Although there was no direct evidence to confirming the Co-Ni complex compound in this study, but we believed it could be further investigated in the future time.

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