奈米二氧化錳-奈米碳球殼核材料之製備及其在超級電容器之應用

Synthesis of CNCs@MnO2 core-shell nanoparticles and its application in supercapacitor

李婷婷(Ting-Ting Lee)

指導教授 ： 李元堯

國立中正大學/工學院/化學工程學系/碩士(2013年)

摘要

我們利用簡單易的方法在100℃下利用過錳酸鉀(KMnO4)及奈米碳球(CNC)以10比1的比例，反應時間6小時下，成功的製作出殼-核型奈米碳球-二氧化錳材料，材料經由掃描式電子顯微鏡、穿透式電子顯微鏡、X光繞射分析儀、比表面積測定儀、X射線光電子能譜儀、拉曼分析儀以及熱重分析儀等分析，證明得到其為表面具有花瓣狀(petal-like)結構的birnessite-type 二氧化錳，其花瓣狀結構是由奈米薄膜平板(thin nano-platelets)所構成。將此材料進行循環伏安法、定電流充放電以及電化學阻抗圖譜量測等電化學性能量測，發現在掃描速率2 mV/s時有162 F/g的比電容表現，循環穩定度測試在100 mV/s的掃描速率下掃5000圈後，還保有97.8% 的高比電容表現，由此可知，我們所合成具有花瓣狀二氧化錳於奈米碳球表面的殼核材料，CNCs@MnO2，可表現出高比電容並且有優秀的高循環穩定性，因此很適合做為超級電容器的電極材料。

關鍵字

殼核結構 ； 奈米碳球 ； 二氧化錳

並列摘要

Petal-like carbon nanocapsule CNCs@MnO2 core shell nanostructures were formed with the reaction of CNC and KMnO4 (aq) at 100℃ for 6 hours study on the growth mechamism found that, in the beginning, birnessite-type MnO2 were grown on the CNCs to form MnO2 nanoplatelets. With increase the reaction time, the amount of the MnO2 nanoplatelets increased so that the petal-like MnO2 structure was therefore formed. The electrochemical properties of the matericals were investigated by the cyclic voltammetry (CV) in 1 M Na2SO4. The result presented a good symmetrical rectangular shape of CV curve, and the specific capacitance was about 166.6 F/g at a scan rate of 2 mV/s. After 5000 cycles of CV at 100 mV/s, the specific capacitance was maintained at about 97.7 %, indicating that the designed structure possessed a high electrochemical stability.

並列關鍵字

Carbon nanocapsule ； Manganese dioxide ； Core-shell

參考文獻

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