氧化鋅奈米線/金屬氧化物複合電極在超級電容器之應用

ZnO nanowires/Metal Oxide composite electrodes for Supercapacitor applications

羅一翔(Lo, I Hsiang)

指導教授 ： 黃金花

國立清華大學/工學院/材料科學工程學系/博士(2016年)

摘要

本研究利用化學浴沉積法，在FTO基板上成長排列有序的氧化鋅奈米線，並利用脈衝電化學沉積法，將奈米片狀結構的氫氧化鎳均勻沉積在氧化鋅奈米線的表面。在研究中針對脈衝電化學沉積法的沉積參數，做了系統性的討論。其中通電時間以及關閉電流時間，會對片狀結構的尺寸以及間隙造成影響；而沉積圈數的多寡，則會對氫氧化鎳殼層的厚度以及片狀結構的大小造成影響。使用最佳化參數所製成的氧化鋅/氫氧化鎳奈米複合材料電極，具有高達1830 F/g的比電容值，51.5 Wh/kg的能量密度以及9 kW/kg的功率密度，但是比電容值維持率在經過1000次掃描後僅有約80 %。
為了改善比電容值維持率，在原先的電鍍液中添加錳的前驅物，並探討其含量對電容性能的影響。另外由於添加錳的前驅物，所以對相關的沉積參數再做一次系統性的討論。最後所製成的氧化鋅/鎳錳氧化物氫氧化物奈米複合材料電極，得到的比電容值為1642 F/g、能量密度為42.2 Wh/kg、功率密度為9 kW/kg以及在3000次掃描有高達94.7 %的比電容值維持率。儘管比電容值下降了近200 F/g，但是成功的將比電容值維持率提升至少15 %，這將有助於擴大超級電容器的應用範圍。

關鍵字

超級電容器 ； 氫氧化鎳 ； 氧化鋅奈米線 ； 脈衝電沉積 ； 奈米複合材料

並列摘要

A high-performance supercapacitor based on Ni(OH)2 nanoflakes modified ZnO nanowires (NWs) was developed. The well-aligned ZnO NWs were synthesized by chemical bath deposition, followed by pulse electrodeposition of Ni(OH)2 nanoflakes on the surface of ZnO NWs. The effects of the pulse electrodeposition conditions were systematically investigated. Both the current-on time and current-off time were found to affect the size and interspacing of the nanoflakes, while the deposition cycle number determines the thickness of the Ni(OH)2 nanoflake shell. The ZnO/Ni(OH)2 nanocomposite electrode fabricated under the optimal pulse electrodeposition conditions has exhibited a large specific capacitance of 1830 F/g, a high energy density of 51.5 Wh/kg, a high power density of 9 kW/kg, and ~80 % specific capacitance retention after 1000 cycles.
To improve the specific capacitance retention, Mn precursor was added into the deposition solution. The optimal amount of Mn precursor and the pulse electrodeposition conditions were discussed. The resultant ZnO/(Ni, Mn) oxide or hydroxide nanocomposite electrode fabricated under the optimal conditions has exhibited a specific capacitance of 1642 F/g, an energy density of 42.2 Wh/kg, a power density of 9 kW/kg, and 94.7 % specific capacitance retention after 3000 cycles. The high supercapacitor performance combined with using of the low-cost and environmentally friendly materials will make the ZnO/(Ni, Mn) oxide or hydroxide nanocomposite electrode desirable for supercapacitor applications.

並列關鍵字

Supercapacitors ； Nickel hydroxide ； ZnO nanowires ； Pulse electrodeposition ； Nanocomposites

參考文獻

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