本研究使用一步驟水熱法成功合成多元之過渡金屬氫氧化物，將材料直接成長於基板上，藉由調整前驅物之過渡金屬元素(鈷、鎳、錳、鐵、鈦)種類多寡，以及調控系統中金屬元素添加之比例，以達到最佳之調配組合，得到卓越之電性表現，並成功應用於超級電容器，由於在材料合成之過程中，鎳發泡基板會參與反應，因此本研究採用面積之方式，以計算電容值，更加具有說服力，本材料在電流密度為1mA/cm2下之比電容值高達2,273 mF/cm2，與高電流密度為10 mA/cm2下電容值為911 mF/cm2，進而計算得到電容保有率(Rate Capability)為40.1%，使用三極式系統進行測試，本材料在經歷五千圈循環壽命之測試後，仍具有極佳之庫倫效率，藉由材料儀器分析，探討各個過渡金屬元素提供之電子價數對於整體材料表現之因果關係，更深入探究材料機制以及暸解其原理。

In this work, we have studied a novel supercapacitor electrode made out of a mixed transition metal hydroxide directly grown on Ni foam. The mixed transition metal hydroxide, Co-Ni-Mn-Fe(OH)2, was synthesized using a one-pot synthesis involving hydrothermal treatment. Fixed the precursor concentration, hydrothermal time as well as hydrothermal temperature. The result show that simply varying the ratio of the transition metal elements would lead to the formation of Co-Ni-Mn-Fe(OH)2 nanostructures having different morphologies. The amount of the Cobalt element increased, the retention improved. Multi-element hydroxides enhance the capacitive performance and electrochemical performance due to its multi valence for Faradaic redox reaction. Several material characterizations and electrochemical tests were performed. Moreover, we demonstrate that the novel electrode gives very excellent specific capacitance of 2,273 mF/cm2 and column efficiency after 5,000 cycles in three electrode system.

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