奈米花狀氧化銅於本研究中利用水相化學反應，以檸檬酸鈉為螯合劑，加入硫酸銅及氫氧化鈉合成。奈米花狀氧化銅直徑約為200至300奈米，BET比表面積為53.1 m2/g，約為市售奈米氧化銅粉末(~29 m2/g)的兩倍。
成長奈米花狀氧化銅的奈米碳管紙在電解液1 M氫氧化鈉做電化學循環伏安法量測，可於-1.2至0.2 V中看到氧化還原反應。奈米花狀氧化銅具有高比表面積且可有多價態的轉換可以同時貢獻電雙層電容和擬電容，此外輕薄的奈米碳管紙可以降低電容的總重量，使成長奈米花狀氧化銅的奈米碳管紙成為具有發展超級電容潛力的電極。

In this study, flower-like CuO grown on carbon nanotube paper was prepared via aqueous-based chemical reaction using copper sulfate as copper source along with sodium hydroxide, and trisodium citrate as chelating agent. The as-prepared flower-like CuO is about 250 nm in diameter. The BET surface area of flower-like CuO (53.1 m2/g) is much larger than that of commercial CuO nanopowder (~29 m2/g).
Cyclic voltammetry showed redox potential between -1.2 V and 0.2 V in sodium hydroxide. Due to the high surface area and multi-oxidation state, flower-like CuO can provide both electric double layer capacitance and pseudocapacitanc. Furthermore, lightweight carbon nanotube paper can reduce the total weight of electrode. To sum up, the flower-like CuO/carbon nanotube paper is a promising electrode for supercapacitors.

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