實電結果表明，恆電流電化學沉積與脈衝電流電化學沉積會影響氫氧化鎳的奈米結構：恆電流所沉積的氫氧化鎳主要是片狀結構；脈衝電流沉積得到的氫氧化鎳主要呈現毛細結構。在沒有銀摻雜的情況下，這二種方法得到的氫氧化鎳超电容，由於其電導性不良，電化學性能與理論值具有較大差異，只達到了氫氧化鎳理論比電容的28.77%和11.60 %。通過拉曼光譜儀的檢測，在電化學反應前後，活性物質從氫氧化鎳轉變為了氧化鎳。在摻雜銀之後，這兩種通電方式製成的氫氧化鎳超電容電化學性能都得到了極大提升，分別達到了理論值的77.66％和79.77％。其中由脈衝電流沉積的銀摻雜氫氧化鎳超電容，銀摻雜的顆粒直徑在5奈米到10奈米之間。 ;Supercapacitors (also called electrochemical capacitors or ultracapacitors) have attracted great interest in recent years because they offer a balanced energy density and power density that bridge the gap between batteries and conventional capacitors [1]. Based on the different energy storage mechanisms, supercapacitors can be generally categorized as electrical double-layer capacitors (EDLCs) and pseudocapacitors. The nickel (II) hydroxide is one of the most used metal oxide supercapacitors active materials.
The object of this work is synthesizing nickel hydroxide based supercapacitors, studying its phase transformations after electrochemical reactions and increasing its specific capacitance by add silver particles inside.
The nickel hydroxide based supercapacitors were fabricated by electrochemical deposition (electrodeposition) with constant current and pulse current. The surface morphologies of the nickel hydroxide were characterized by emission scanning electron microscope at 20 kV. The particle size of silver was measured by transmission electron microscope at 200 kV. The phase transformations of nickel hydroxide were examined by Raman spectroscopy using green laser with a wavelength of 537 nm. The electrochemical measurements were carried out in a standard three-electrode cell by an electrochemical workstation.
This work consisted of bibliographies studies about this subject; The synthesis of nickel hydroxide nanoflakes; The surface morphology studies and the phase transformations studies.
